This manual covers the service and repair procedures for Honda WX10T water pump. All information contained in this manual is based on the latest product information available at the time of printing. We reserve the right to make changes at anytime without notice.
How to use this manual A Few Words About Safety How to use this manual SERVICE INFORMATION The service and repair information contained in this manual is intended for use by qualified, professional technicians. Attempting service or repairs without the proper training, tools, and equipment could cause injury to you and/or others. It could also ...
Replace the crankshaft if it is damaged or deformed. CYLINDER SLEEVE I.D. ... CYLINDER HEAD. CYLINDER HEAD INNER COVER. Check the oil return passage of the ...
dummyhead How to use this manual A Few Words About Safety Howtousethismanual SERVICE INFORMATION The service and repair information contained in this manual is intended for use by qualified, professional technicians. Attempting service or repairs without the proper training, tools, and equipment could cause injury to you and/or others. It could also damage this Honda product or create an unsafe condition. This manual describes the proper methods and procedures for performing service, maintenance, and repairs. Some procedures require the use special tools. Any person who intends to use a replacement part, service procedure, or a tool that is not recommended by Honda must determine the risks to their personal safety and the safe operation of this product. If you need to replace a part, use Honda Genuine parts with the correct part number or an equivalent part. We strongly recommend that you do not use replacement parts of inferior quality. For Your Customer's Safety Proper service and maintenance are essential to the customer's safety and the reliability of this product. Any error or oversight while servicing this product can result in faulty operation, damage to the product, or injury to others. Improper service or repairs can create an unsafe condition that can cause your customer or others to be seriously hurt or killed. Follow the procedures and precautions in this manual and other service materials carefully. For Your Safety Because this manual is intended for the professional service technician, we do not provide warnings about many basic shop safety practices (e.g., Hot parts-wear gloves). If you have not received shop safety training or do not feel confident about your knowledge of safe servicing practices, we recommend that you do not attempt to perform the procedures described in this manual. Some of the most important general service safety precautions are given below. However, we cannot warn you of every conceivable hazard that can arise in performing service and repair procedures. Only you can decide whether or not you should perform a given task. Failure to properly follow instructions and precautions can cause you to be seriously hurt or killed. Follow the procedures and precautions in this manual carefully. Important Safety Precautions Make sure you have a clear understanding of all basic shop safety practices and that you are wearing appropriate clothing and using safety equipment. When performing any service task, be especially careful of the following: · Read all of the instructions before you begin, and make sure you have the tools, the replacement or repair parts, and the skills required to perform the tasks safely and completely. · Protect your eyes by using proper safety glasses, goggles, or face shields anytime you hammer, drill, grind, or work around pressurized air, pressurized liquids, springs, or other stored-energy components. If there is any doubt, put on eye protection. · Use other protective wear when necessary, for example gloves or safety shoes. Handling hot or sharp parts can cause severe burns or cuts. Before you grab something that looks like it can hurt you, stop and put on gloves. · Protect yourself and others whenever you have equipment hoisted in the air. Anytime you lift this product with a hoist, make sure that the hoist hook is securely attached to the product. Make sure the engine is off before you begin any servicing procedures, unless the instruction tells you to do otherwise. This will help eliminate several potential hazards: · Carbon monoxide poisoning from engine exhaust. Be sure there is adequate ventilation whenever you run the engine. · Burns from hot parts. Let the engine and exhaust system cool before working in those areas. · Injury from moving parts. If the instruction tells you to run the engine, be sure your hands, fingers and clothing are out of the way. Gasoline vapors and hydrogen gasses from batteries are explosive. To reduce the possibility of a fire or explosion, be careful when working around gasoline or batteries. · Use only a nonflammable solvent, not gasoline, to clean parts. · Never store gasoline in an open container. · Keep all cigarettes, sparks, and flames away from the battery and all fuel-related parts. 0-1 dummyhead CONTENTS SPECIFICATIONS 1 SERVICE INFORMATION 2 MAINTENANCE 3 TROUBLESHOOTING 4 COVER 5 FUEL SYSTEM 6 CONTROL SYSTEM 7 IGNITION SYSTEM 8 STARTING SYSTEM 9 PUMP 10 ENGINE REMOVAL/INSTALLATION 11 CRANKCASE 12 CYLINDER HEAD 13 MUFFLER 14 INDEX dummyhead How to use this manual INTRODUCTION This manual covers the service and repair procedures for Honda WX10T water pump. All information contained in this manual is based on the latest product information available at the time of printing. We reserve the right to make changes at anytime without notice. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form, by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of the publisher. This includes text, figures, and tables. As you read this manual, you will find information that is preceded by a prevent damage to this Honda product, other property, or the environment. symbol. The purpose of this message is to help SAFETY MESSAGES Your safety, and the safety of others, are very important. To help you make informed decisions, we have provided safety messages and other safety information throughout this manual. Of course, it is not practical or possible to warn you about all the hazards associated with servicing these products. You must use your own good judgment. You will find important safety information in a variety of forms, including: · Safety Labels on the product. · Safety Messages preceded by a safety alert symbol and one of three signal words, DANGER, WARNING, or CAUTION. These signal words mean: You WILL be KILLED or SERIOUSLY HURT if you don't follow instructions. You CAN be KILLED or SERIOUSLY HURT if you don't follow instructions. You CAN be HURT if you don't follow instructions. · Instructions how to service these products correctly and safely. ALL INFORMATION, ILLUSTRATIONS, DIRECTIONS AND SPECIFICATIONS INCLUDED IN THIS PUBLICATION ARE BASED ON THE LATEST PRODUCT INFORMATION AVAILABLE AT THE TIME OF APPROVAL FOR PRINTING. Honda Motor Co., Ltd. RESERVES THE RIGHT TO MAKE CHANGES AT ANY TIME WITHOUT NOTICE AND WITHOUT INCURRING ANY OBLIGATION WHATSOEVER. NO PART OF THIS PUBLICATION MAY BE REPRODUCED WITHOUT WRITTEN PERMISSION. THIS MANUAL IS WRITTEN FOR PERSONS WHO HAVE ACQUIRED BASIC KNOWLEDGE OF MAINTENANCE ON Honda products. © Honda Motor Co., Ltd. SERVICE PUBLICATION OFFICE Date of Issue: September 2014 0-3 dummyhead How to use this manual SERVICE RULES · Use Honda Genuine or Honda-recommended parts and lubricants or their equivalents. Parts that do not meet Honda's design specifications may damage the unit. · Use the special tools designed for the product. · Install new gaskets, O-rings, etc. when reassembling. · When torquing bolts or nuts, begin with larger-diameter or inner bolts first and tighten to the specified torque diagonally, unless a particular sequence is specified. · Clean parts in cleaning solvent upon disassembly. Lubricate any sliding surfaces before assembly. · After assembly, check all parts for proper installation and operation. · Many screws used in this machine are self-tapping. Be aware that cross-threading or overtightening these screws will strip the threads and ruin the hole. Use only metric tools when servicing this unit. Metric bolts, nuts and screws are not interchangeable with non-metric fasteners. The use of incorrect tools and fasteners will damage the unit. SYMBOLS The symbols used throughout this manual show specific service procedures. If supplementary information is required pertaining to these symbols, it will be explained specifically in the text without the use of the symbols. Replace the part(s) with new one(s) before assembly. Use the recommend engine oil, unless otherwise specified. Use molybdenum oil solution (mixture of the engine oil and molybdenum grease in a ratio of 1:1). Use multi-purpose grease (lithium based multi-purpose grease NLGI #2 or equivalent). Use marine grease (water resistant urea based grease). Apply a locking agent. Use a medium strength locking agent unless otherwise specified. Apply sealant. x () page 1-1 Use automatic transmission fluid. Indicates the diameter, length, and quantity of metric bolts used. Indicates the reference page. 0-4 dummyhead How to use this manual ABBREVIATIONS Throughout this manual, the following abbreviations are used to identify the respective parts or systems. Abbreviated term ACG API Approx. Assy. ATDC ATF ATT AVR BAT BDC BTDC BARO CKP Comp. CMP CYL DLC D-AVR EBT ECT ECM EMT EOP EX F GND HO2S IAB IAC IAT I.D. IG or IGN IN INJ L. MAP MIL O.D. OP PGM-FI P/N Qty R. SAE SCS STD SW TDC Full term Alternator American Petroleum Institute Approximately Assembly After Top Dead Center Automatic Transmission Fluid Attachment Auto Voltage Regulator Battery Bottom Dead Center Before Top Dead Center Barometric Pressure Crankshaft Position Complete Camshaft Position Cylinder Data Link Connector Digital Auto Voltage Regulator Engine Block Temperature Engine Coolant Temperature Engine Control Module Exhaust Manifold Temperature Engine Oil Pressure Exhaust Front or Forward Ground Heated Oxygen sensor Intake Air Bypass Idle Air Control Intake Air Temperature Inside diameter Ignition Intake Injection Left Manifold Absolute Pressure Malfunction Indicator Lamp Outside Diameter Optional Part Programmed-Fuel Injection Part Number Quantity Right Society of Automotive Engineers Service Check Signal Standard Switch Top Dead Center BI Black Y Yellow BU Blue G Green R Red W White Br Brown Lg Light green O Orange P Pink Lb Light blue Gr Gray 0-5 dummytext 1. SPECIFICATIONS 1 SERIAL NUMBER LOCATION ················· 1-2 SPECIFICATIONS·································· 1-2 PERFORMANCE CURVE ························ 1-4 DIMENSIONAL DRAWINGS ···················· 1-5 1-1 dummyhead SPECIFICATIONS SERIAL NUMBER LOCATION SPECIFICATIONS The engine serial number [1] is located on the cylinder barrel. The frame serial number [2] is located on the frame. Refer to these numbers when ordering parts and when making technical inquiries. [1] [2] SPECIFICATIONS DIMENSIONS AND WEIGHTS Model Description code Type Overall length Overall width Overall height Dry weight Operating weight 1-2 WX10T WAGT A/C 340 mm (13.4 in) 220 mm (8.7 in) 295 mm (11.6 in) 6.1 kg (13.4 lbs) 6.5 kg (14.3 lbs) dummyhead ENGINE Engine model Description code Type Displacement Bore x stroke Compression ratio Ignition system Ignition timing Spark plug Lubrication system Oil capacity Recommended oil Cooling system Starting system Stopping system Carburetor Air cleaner Breather system Fuel tank capacity Fuel used WATER PUMP Model Type Drive system Suction port diameter Discharge port diameter Maximum total head Maximum suction head Maximum discharge capacity Maximum discharge pressure Maximum self-feed time Approx. operating hours (at max discharge) SPECIFICATIONS A type C type GX25T GCALT 4 stroke, OHC, single cylinder 25 cm3 (1.5 cuin) 35.0×26.0 mm (1.38 x 1.02 in) 8.0±0.5 Transistor magneto ignition B.T.D.C. 30°±2° CMR5H (NGK) Pumping spray system 0.08 liter (0.08 US qt, 0.07 Imp qt) SAE 10W 30 API service classification SJ or later SAE 10W 30 API service classification SE or higher Forced air Recoil starter Ignition primary circuit ground Diaphragm type Semi-dry type Reed valve type 0.53 liter (0.021 US gal, 0.018 Imp gal) Unleaded gasoline with a pump octane rating 86 or higher WX10T Self priming centrifugal pump Direct connection engine 25 mm (1.0 in) 25 mm (1.0 in) 37 m (121 ft) 8 m (26.2 ft) 120 liters (31.7 US gal, 26.4 Imp gal) /min 359 kPa (52 psi) 80 sec at 5 m (16.4 ft) 0.9 Hr. 1-3 dummyhead SPECIFICATIONS PERFORMANCE CURVE TOTAL HEAD LIFT (feet) (m) 40 120 100 30 80 20 60 40 10 20 50 10 10 100 150 (Liters/min) 20 30 (US gal/min) 20 30 (Imp gal/min) DISCHARGE CAPACITY 1-4 dummyhead DIMENSIONAL DRAWINGS SPECIFICATIONS Unit: mm (in) 295 (11.6 in) 220 (8.7 in) 340 (13.4 in) 1-5 dummyhead MEMO dummytext 2. SERVICE INFORMATION 2 MAINTENANCE STANDARDS ················· 2-2 TORQUE VALUES ································· 2-3 LUBRICATION & SEAL POINT ················ 2-4 TOOLS ················································ 2-5 HARNESS AND TUBE ROUTING ············· 2-6 2-1 dummyhead SERVICE INFORMATION MAINTENANCE STANDARDS SERVICEINFORMATION ENGINE Part Engine Cylinder Piston Piston pin Piston rings Connecting rod Cylinder barrel Valves Campulley Carburetor Spark plug Ignition coil Engine P.T.O. shaft Item Idle speed Cylinder compression Sleeve I.D. Skirt O.D. Piston-to-cylinder clearance Piston pin bore I.D. Pin O.D. Piston pin-to-piston pin bore clearance Ring side clearance Top/second Ring end gap Top/second Ring width Top/second Small end I.D. Barrel I.D. (Cam pulley bearing) Valve clearance IN EX Valve stem O.D. IN EX Valve guide I.D. IN/EX Guide-to-stem IN clearance EX Valve spring free length Cam height Campulley I.D. Campulleyshaft O.D. Main jet Gap Air gap Primary resistance Secondary resistance Shaft O.D. Standard 4,100 ± 200 min-1 (rpm) 0.90 MPa (9.2 kgf/cm2, 131 psi)/2.000 min-1 (rpm) 35.000 - 35.015 (1.3780 1.3785) 34.970 - 34.990 (1.3768 1.3776) 0.010 - 0.045 (0.0004 0.0018) 8.010 - 8.026 (0.3154 0.3160) 7.994 - 8.000 (0.3147 0.3150) 0.010 - 0.032 (0.0004 0.0013) 0.015 - 0.056 (0.0006 0.0022) 0.10 - 0.25 (0.004 0.010) 0.970 - 0.990 (0.0382 0.0390) 7.978 - 7.989 (0.3141 0.3145) 4.000 - 4.018 (0.1575 0.1582) 0.08 ± 0.02 (0.003 0.001) 0.11 ± 0.02 (0.004 0.001) 3.470 - 3.485 (0.1366 0.1372) 3.435 - 3.450 (0.1352 0.1358) 3.500 - 3.518 (0.1378 0.1385) 0.015 - 0.048 (0.0006 0.0019) 0.050 - 0.083 (0.0020 0.0033) 20.66 (0.8621) 21.897 - 22.297(0.8621 0.8778) 4.020 - 4.050 (0.1583 0.1594) 3.990 - 4.000 (0.1571 0.1575) # 34 0.60 - 0.70 (0.024 0.028) 0.2 - 0.4 (0.01 0.02) 0.585 - 0.715 4.77 - 5.83 k 11.966 - 11.984 (0.4711 0.4718) PUMP Part Pump Item Impeller Clearance Standard 0.70 - 1.00 (0.028 0.039) Unit: mm (in) Service limit 35.100 (1.3819) 34.900 (1.3740) 0.120 (0.0047) 8.060 (0.3173) 7.950 (0.3130) 0.070 (0.0028) 0.120 (0.0047) 0.60 (0.024) 0.920 (0.0362) 4.050 (0.1594) 3.400 (0.1339) 3.380 (0.1331) 3.560 (0.1402) 0.098 (0.0039) 0.120 (0.0047) 20.00 (0.787) 21.797 (0.8581) 4.100 (0.1614) 3.950 (0.1555) 11.800 (0.4646) Unit: mm (in) Service limit 2-2 dummyhead TORQUE VALUES ENGINE Item Spark plug Fan cover bolt Lower crankcase bolt Thread Dia. (mm) M10×1.0 M5×0.8 M5×0.8 (CT) Recoil starter pulley Flywheel nut Ignition coil bolt Oil outlet valve screw Adjusting screw lock nut Top cover bolt Muffler stud bolt M6×1.0 M7×1.0 M4×0.7 M4×0.7 M5×0.5 M5×0.8 M5×0.8 PUMP Item Impeller Casing cover bolt Thread Dia. (mm) M8×1.25 M5×0.8 STANDARD TORQUE VALUES ENGINE Screw Item Bolt and nut CT (Cutting threads) flange bolt (Retightening) FRAME Screw Item Bolt and nut Flange bolt and nut SH (Small head) flange bolt CT (Cutting threads) flange bolt (Retightening) SERVICE INFORMATION Torque values N·m kgf·m lbf·ft 11.8 1.2 9 6.4 0.65 4.7 6.4 0.65 4.7 6.4 0.65 4.7 14.7 1.5 11 3.9 0.40 2.9 3.0 0.31 2.2 4.9 0.50 3.6 3.0 0.31 2.2 4.4 0.45 3.2 Remark CT (Cutting Thread) indicates a self-tapping bolt. Torque values N·m kgf·m lbf·ft 6.9 0.70 5.1 5.0 0.51 3.7 Remark Thread Dia. (mm) 3 mm 4 mm 4 mm 5 mm 6 mm 5 mm Thread Dia. (mm) 4 mm 5 mm 6 mm 5 mm 6 mm 8 mm 10 mm 12 mm 5 mm 6 mm 8 mm 10 mm 6 mm 5 mm 6 mm Torque values N·m kgf·m lbf·ft 1.0 0.10 0.7 2.1 0.21 1.5 3.4 0.35 2.5 5.4 0.55 4.0 9.8 1.00 7.2 5.9 0.60 4.4 Torque values N·m kgf·m lbf·ft 2.1 0.21 1.5 4.3 0.44 3.2 9.0 0.92 6.6 5.3 0.54 3.9 10 1.0 7 22 2.2 16 34 3.5 25 54 5.5 40 5.3 0.54 3.9 12 1.2 9 27 2.7 20 40 4.1 30 9.0 0.92 6.6 5.4 0.55 4.0 12 1.2 9 2-3 dummyhead SERVICE INFORMATION LUBRICATION & SEAL POINT ENGINE Material Molybdenum disulfide oil (mixture of the engine oil and molybdenum grease in a ratio of 9:1) Engine oil Multi-purpose grease Liquid sealant (ThreeBond® #1216E, Hondabond HT or equivalent) Locking agent (ThreeBond® #1322N, Hondalock 2 or equivalent) Location Piston outer surface Piston rings Piston pin outer surface Cylinder barrel inner surface Each ball bearing rolling surface Cam pulley cam profile and journal Cam pulley decompressor pin whole surface Cam pulley gear teeth Valve lifter shaft whole surface and journal Valve lifter slipper Valve stem sliding surface Valve spring whole surface Oring Flywheel nut threads and seating surface Oil seal lip Recoil starter case (Recoil starter reel sliding area) Cylinder barrel and the lower crankcase mating surfaces Shroud mounting socket bolt Remarks 2-4 dummyhead TOOLS Piston base 07VPF-ZM3010B Push rod 07VPF-ZM3020A SERVICE INFORMATION Guide 07VPF-ZM3030A Rocker arm replacement tool 070PF-Z0HA100 Mechanical seal installer 07965-415000A Attachment, 24 x 26 mm 07746-0010700 Pilot, 12 mm 07746-0040200 Driver 07749-0010000 Attachment, 28 x 30 mm 07946-1870100 Vacuum gauge 07APJ-YB3A100 25 20 0.6 0.8 1 0.4 0.2 0 100"BxHARgkPa 30 0 2-5 dummyhead SERVICE INFORMATION HARNESS AND TUBE ROUTING HIGH TENSION CORD SHROUD STOP SWITCH CORD SHROUD SHROUD GROOVE STOP SWITCH CORD 2-6 STOP SWITCH CORD dummyhead TUBE CLIP CARBURETOR FUEL TANK 5 -(06.2m0m- 0.24 in) SERVICE INFORMATION VIEWED FROM LOWER SIDE: CARBURETOR FUEL RETURN TUBE TUBE CLIP FUEL FEED TUBE TUBE CLIP 2-7 dummyhead MEMO dummytext 3. MAINTENANCE 3 TOOL··················································· 3-2 MAINTENANCE SCHEDULE ··················· 3-3 ENGINE OIL LEVEL CHECK/CHANGE······ 3-4 AIR CLEANER CHECK/CLEANING ·········· 3-5 SPARK PLUG CHECK/ADJUSTMENT ······ 3-6 SPARK PLUG REPLACEMENT ··············· 3-6 SPARK ARRESTER CLEANING ·············· 3-7 IDLE SPEED CHECK/ADJUSTMENT ········ 3-7 VALVE CLEARANCE CHECK/ADJUSTMENT··························· 3-8 COMBUSTION CHAMBER CLEANING······ 3-9 FUEL TANK/FUEL FILTER CLEANING FUEL TUBES CHECK ···························· 3-9 IMPELLER CHECK ······························ 3-10 IMPELLER CLEARANCE CHECK ·········· 3-11 PUMP INLET VALVE CHECK ················ 3-12 PUMP VACUUM TEST·························· 3-13 3-1 dummyhead MAINTENANCE TOOL MAINTENANCE Cleaning brush (commercially available) Vacuum tester 07APJ-YB3A100 25 30 1B0A0Rx 0.8 1 Kpa "Hg 0.6 0.2 0 20 0.4 15 3-2 dummyhead MAINTENANCE SCHEDULE MAINTENANCE ITEM Perform at every indicated month or operating hour interval, whichever comes first. Engine oil Air cleaner Spark plug Spark arrester (applicable types) Engine cooling fins Nuts, bolts, fasteners Idle speed Valve clearance Combustion chamber Fuel filter Fuel tank Fuel tube Oil tube Impeller Impeller clearance Pump inlet valve Check level Change Check Clean Checkadjust Replace Clean Clean Check (Retighten if necessary) Checkadjust Checkadjust Clean Clean Clean Check Check Check Check Check Each use REGULAR SERVICE PERIOD (2) First month or 10 hrs. Every 3 months or 25 hrs. Every 6 months or 50 hrs. Every year or 100 hrs. (1) After every 300 hours(3) Every 2 years (Replace if necessary) Every 2 years (Replace if necessary) (1) Service more frequently when used in dusty areas. (2) For commercial use, log hours of operation to determine proper maintenance intervals. Every two years or 300 hrs. Refer to page 3-4 3-4 3-5 3-5 3-6 3-6 3-7 - 3-7 3-8 3-9 3-9 3-9 3-9 12-3 3-10 3-11 3-13 3-3 dummyhead MAINTENANCE ENGINE OIL LEVEL CHECK/CHANGE CHECK SERVICE BULLETIN #9 Place the water pump on a level surface. [1] Remove the oil filler cap [1] and verify the oil level is at the top of the oil filler neck [2]. [3] [2] If the oil level is low, fill with recommended oil to the top of the oil filler neck (page 3-4). Check that the oil filler packing [3] is in good condition; replace it if necessary. Install and tighten the oil filler cap securely. CHANGE Drain the oil in the engine while the engine is warm. Warm oil drains quickly and completely. Check that the fuel tank cap [1] is tightened securely. Remove the oil filler cap [2]. Tilt the engine toward the oil filler cap side and drain the [1] used oil in a suitable container. Dispose of used engine oil in a manner that is compatible with the environment. We suggest you take used oil in a sealed container to your local recycling center or service station for reclamation. Do not throw it in the trash, pour it into the ground, or down a drain. Used engine oil contains substances that have been identified as carcinogenic. If repeatedly left in contact with the skin for prolonged periods, it may cause skin cancer. Wash your hands thoroughly with soap and water as soon as possible after contact with used engine oil. Fill with recommended oil to the upper level. ENGINE OIL CAPACITY: 0.08 Liters (0.08 US qt, 0.07 lmp qt) RECOMMENDED OIL: A type: SAE 10W-30 API service classification: SJ or later C type: SAE 10W-30 API service classification: SE or higher Tighten the oil filler cap. [2] SAE VISCOSITY GRADES AMBIENT TEMPERATURE 3-4 dummyhead AIR CLEANER CHECK/CLEANING CHECK A dirty air cleaner will restrict air flow to the carburetor, reducing engine performance. If the engine is operated [1] in dusty areas, clean the air cleaner more often than specified in the MAINTENANCE SCHEDULE. Remove the air cleaner cover [1] and air cleaner element [2]. Inspect the air cleaner element for holes or tears, and replace if damaged. Installation is in the reverse order of removal. MAINTENANCE CLEANING Clean the element [1] in warm soapy water [2], rinse and allow to dry thoroughly, or clean with a high flash point solvent and allow to dry. Dip the element in clean engine oil [3] and squeeze out all the excess oil. Wash [2] [3] Dip · Excess oil will restrict air flow through the foam element and may cause the engine to smoke at startup. · Do not twist to squeeze oil from the air cleaner element. Twisting the element can damage it. [1] Squeeze and dry [2] Squeeze thoroughly 3-5 dummyhead MAINTENANCE SPARK PLUG CHECK/ADJUSTMENT Remove the spark plug (page 3-6). Clean the spark plug [1] electrodes with a wire brush [2] [1] or special plug cleaner. Check the following and replace if necessary. Insulator [3] and sealing washer [4] for damage Center electrode [5] and side electrode [6] for wear Burning condition, coloration RECOMMENDED SPARK PLUG: CMR5H (NGK) Measure the plug gap with a wire-type feeler gauge. PLUG GAP: 0.60 0.70 mm (0.024 0.028 in) If the measurement is out of the specification, adjust by bending the side electrode. Install the spark plug (page 3-6). [2] [4] [5] [3] SPARK PLUG REPLACEMENT REMOVAL 3-6 The muffler becomes very hot during operation and remains hot for a while after stopping the engine. Touching a hot muffler can severely burn you. Allow the muffler to cool before proceeding. Remove the top cover (page 5-2). Disconnect the spark plug cap [1] and remove the spark plug [2]. · Clean around the spark plug base with compressed air before removing the spark plug and be sure that no debris is allowed to enter into the combustion chamber. INSTALLATION Install and hand tighten the spark plug to the cylinder barrel. RECOMMENDED SPARK PLUG: [1] CMR5H (NGK) Tighten the spark plug to the specified torque. TORQUE: 11.8 N·m (1.2 kgf·m, 9 lbf·ft) Connect the spark plug cap. [6] [2] dummyhead SPARK ARRESTER CLEANING (Applicable types) The muffler becomes very hot during operation and remains hot for a while after stopping the engine. Touching a hot muffler can severely burn you. Allow the muffler to cool before proceeding. Remove the top cover (page 5-2). Remove the two screws (4 x 6 mm) [1] from the spark arrester [2], and remove the spark arrester from the muffler. Check for carbon deposits around the exhaust port and spark arrester. Clean if necessary, with a wire brush [1]. Replace the spark arrester if there are any breaks or tears. Installation is in the reverse order of removal. MAINTENANCE [1] [2] [1] IDLE SPEED CHECK/ADJUSTMENT Remove any hoses attached to the suction and discharge ports. Remove the housing fill plug. Running the engine with the housing dry will damage the pump. Fill the housing with water and reinstall the fill plug. Use a tachometer with graduations of 50 min-1 (rpm) or smaller that will accurately indicate 50 min-1 (rpm) change. Start the engine and then move the throttle lever to the idle position. Allow it to warm up to normal operating temperature. Then, adjust the idle speed by turning the throttle stop screw [1] right or left. IDLE SPEED: 4,100 ± 200 min-1 (rpm) Once completed, drain the water from the housing. [1] 3-7 dummyhead MAINTENANCE VALVE CLEARANCE CHECK/ADJUSTMENT Valve clearance inspection and adjustment must be performed with the engine cold. [1] Remove the top cover (page 5-2). Disconnect the spark plug cap from the spark plug. Remove the two socket bolts [1] and head cover [2]. · Engine oil can leak out when removing the head cover. Catch the leaking oil with a suitable material and wipe up the area immediately. [2] Set the piston at top dead center of the compression stroke. Align the " " mark [1] on the cam pulley [1] with the cylinder head center [2]. If the exhaust valve and intake valve are opened, align the mark on the starter pulley with the mark on the fan cover again by rotating the engine 360°. [2] Insert a feeler gauge [1] between the valve rocker arm [2] and valve stem [3] to measure the valve clearance. VALVE CLEARANCE: IN: 0.08 ± 0.02 mm EX: 0.11 ± 0.02 mm [5] If adjustment is necessary, proceed as follows. Loosen the valve adjusting lock nut [4] and adjust the valve clearance by turning the adjusting screw [5] right or left. Hold the valve adjusting screw and tighten the valve [4] adjusting screw lock nut to the specified torque. TORQUE: 4.9 N·m (0.50 kgf·m, 3.6 lbf·ft) Recheck the valve clearance, and if necessary, readjust the clearance. [1] [3] [2] Install the head cover and top cover. 3-8 dummyhead COMBUSTION CHAMBER CLEANING Prepare a cylinder of thick paper or equivalent material, with a diameter large enough to fit against the inner wall of the cylinder, and insert it into the cylinder for protection. Attach a commercially available cleaning brush [1] to an electric drill and clean the combustion chamber. · Clean the combustion chamber when the valves have been installed in the cylinder block. · Be sure to insert thick paper into the cylinder to protect the inner wall of the cylinder when cleaning the combustion chamber. · Do not press the cleaning brush with force against the combustion chamber. FUEL TANK/FUEL FILTER CLEANING FUEL TUBES CHECK Gasoline is highly flammable and explosive. You can be burned or seriously injured when handling fuel. · Keep heat, sparks and flame away. · Handle fuel only outdoors. · Wipe up spills immediately. Remove the fuel tank [1] (page 6-2). Remove the following from the fuel tank. Fuel tank cap [2] [3] Fuel tube [3] Fuel filter [4] Grommet [5] [2] FUEL TANK CLEANING Wash inside the fuel tank with nonflammable solvent to remove any foreign material and water from the tank. FUEL TUBES CHECK Check the fuel tube and grommet for deterioration, hardening, cracks or signs of leakage. Replace if necessary. MAINTENANCE [1] [4] [5] [1] 3-9 dummyhead MAINTENANCE FUEL FILTER CLEANING Clean the fuel filter [1] with solvent and allow it to dry thoroughly. Replace the fuel filter if it is contaminated. Installation is in the reverse order of removal. After Installation, check for any sign of fuel leakage. IMPELLER CHECK Remove the volute case [1] (page 10-4). Check the volute [1] and impeller [2] for damage or excessive wear and replace if necessary. [1] [2] [1] 3-10 dummyhead IMPELLER CLEARANCE CHECK Remove the volute case [1] (page 10-4). Measure the depth [2] of the volute case by using the depth gauge or vernier caliper. MAINTENANCE [1] [2] Measure the height of the impeller vanes [1] from the casing cover [2]. [1] [2] 3-11 dummyhead MAINTENANCE Subtract the height of the impeller [1] from the depth of the volute case [2] to obtain the impeller clearance [3]. IMPELLER CLEARANCE: 0.70 r 1.00 mm (0.028 0.039 in) If the clearance is not within specification, adjust the clearance by adding or removing adjuster shims [4] (page 10-5). SHIM THICKNESS: 0.3 mm (0.012 in) PUMP INLET VALVE CHECK Remove the inlet pipe [1] (page 10-3). Check the pump inlet valve [2] for damage or excessive wear and replace if necessary. [2] [1] [3] [4] [2] [1] 3-12 dummyhead PUMP VACUUM TEST Test Procedure Install thread tape or sealant to the vacuum gauge and install in the base plate. Position a garden hose [1] so a steady stream of water flows into the discharge port during the test. Start the engine, position the throttle lever in the FAST position and allow the engine to warm up for several minutes. Adjust the throttle lever to the maximum position. Position the vacuum tester [2] against the suction port to obtain the vacuum reading. MINIMUM VACUUM: 22 in.Hg at sea level Vacuum reading will decrease by approximately 1 in.Hg per 1000 ft increase in elevation. Shut off the engine and confirm the vacuum gauge reading remains steady. This verifies the intake flapper is sealing. Test Results If the vacuum gauge does not remain steady after shutting off the engine, remove any fittings from the suction port (if installed) and retest. If the vacuum gauge is still unsteady, disassemble and inspect the flapper for wear or damage. A vacuum reading below 22 in.Hg (at sea level) indicates a problem with the pump. If the vacuum reading is low, inspect the: · Impeller and volute for damage or wear · Impeller/volute clearance · Mechanical seal for damage · Pump case housing and O-rings for damage or leaks If the pump does not prime, but the vacuum reading is good, there is likely an air leak in the suction hose or fittings, or the suction head is too high. [2] Kpa "Hg 0.2 0 1B0A0Rx 0.4 0.8 1 30 0.6 15 20 MAINTENANCE [1] 25 3-13 dummyhead MAINTENANCE 3-14 dummytext 4. TROUBLESHOOTING 4 BEFORE TROUBLESHOOTING ··············· 4-2 ENGINE TROUBLESHOOTING ················ 4-2 WATER PUMP TROUBLESHOOTING ······· 4-5 4-1 dummyhead TROUBLESHOOTING BEFORE TROUBLESHOOTING TROUBLESHOOTING · Check that the connectors are connected securely. · Check for sufficient fresh fuel in the fuel tank. · Read the circuit tester's operation instructions carefully, and observe the instructions during inspection. ENGINE TROUBLESHOOTING HARD STARTING Check whether the fuel is reaching the carburetor Not reaching to carburetor by pushing the primer bulb. Fuel reached the carburetor Remove the spark plug and check for wet or Wet fouled electrode. Normal Dry Check for blockage of the fuel tube or fuel filter (page 3-9). Check for blockage and wear of the carburetor diaphragm or valve (page 6-5). Clean the electrode and restart, taking care that the choke is not closed too much. If flooding is severe, check the carburetor float valve. Check for blockage in the carburetor (page 6-5). Perform the spark test (page 8-8). Spark Check the cylinder compression (page 13-10). Normal Install the spark plug and start the engine according to the starting procedure. No spark Abnormal Perform the IGNITION SYSTEM TROUBLESHOOTING (page 8-3). Check the valve clearance (page 3-8), and then perform the cylinder compression test. If the cylinder compression is too high, remove carbon deposits in the combustion chamber (page 3-9). If the cylinder compression is too low, check the following. - Valve spring free length (page 13-11) - Valve face irregularly worn (page 13-5) - Decompressor operation (page 13-10) - Piston ring side clearance (page 12-11) - Piston ring width (page 12-12) - Piston ring end gap (page 12-12) - Piston skirt O.D. (page 12-10) - Cylinder sleeve I.D. (page 12-10) - Piston-to-cylinder clearance (page 12-10) 4-2 dummyhead POOR PERFORMANCE AT LOW SPEED Check the air cleaner element (page 3-5). Clean Check the spark plug (page 3-6). Normal Check the fuel tube (page 3-9). Normal Clogged or saturated Abnormal Abnormal Check for secondary air leak. No air leaking Air leaking Check the fuel filter (page 3-9). Clean Check the carburetor (page 6-5). Normal Clogged or saturated Abnormal Check the cylinder compression (page 13-10). Normal Abnormal Install the spark plug and start the engine according to the starting procedure. TROUBLESHOOTING Clean or replace the air cleaner element (page 3-5). Inspect the spark plug and adjust the spark plug gap (page 3-6). Replace if necessary (page 3-6). Straighten the fuel tube if it is bent or pinched. Replace if necessary (page 6-2). Check around the air intake joint and carburetor; replace the insulator and/or gasket if necessary. Clean or replace the fuel filter (page 6-2). Disassemble and clean; replace if necessary (page 6-5). Check the valve clearance (page 3-8), and then perform the cylinder compression test. If the cylinder compression is too high, remove carbon deposits in the combustion chamber (page 3-9). If the cylinder compression is too low, check the following. - Valve spring free length (page 13-11) - Valve face irregularly worn (page 13-5) - Decompressor operation (page 13-10) - Piston ring side clearance (page 12-11) - Piston ring width (page 12-12) - Piston ring end gap (page 12-12) - Piston skirt O.D. (page 12-10) - Cylinder sleeve I.D. (page 12-10) - Piston-to-cylinder clearance (page 12-10) 4-3 dummyhead TROUBLESHOOTING POOR PERFORMANCE AT HIGH SPEED Check the air cleaner element (page 3-5). Clogged or saturated Clean Check the spark plug (page 3-6). Abnormal Normal Check the fuel tube (page 3-9). Abnormal Normal Check the carburetor (page 6-5). Normal Abnormal Install the spark plug and start the engine according to the starting procedure. Clean or replace the air cleaner element (page 3-5). Inspect the spark plug and adjust the spark plug gap (page 3-6). Replace if necessary (page 3-6). Straighten the fuel tube if it is bent or pinched. Replace if necessary (page 6-2). Disassemble and clean; replace if necessary (page 6-5). 4-4 dummyhead WATER PUMP TROUBLESHOOTING Won`t prime Perform a vacuum test (page 3-11). 22 in.Hg or higher Less than 22 in.Hg Mechanical seal damaged. Inlet valve damaged. Impeller clearance excessive. Impeller or volute case damaged. Suction hose damaged. Suction hose leak. Suction head too great. Strainer clogged. Strainer damaged. Priming water too low. Throttle lever not in fast. TROUBLESHOOTING Replace (page 10-6). Replace (page 10-3). Replace worn or damaged parts. Adjust (page 3-11). Replace (page 10-5). Replace (page 10-3). Confirm fitting is secure and gasket is present. Move pump closer to water source. Clean out. Replace. Fill pump housing with water. Move lever to fast. 4-5 dummyhead TROUBLESHOOTING Discharge volume or pressure too low Suction hose air leak. Strainer clogged. Suction hose damaged. Mechanical seal damaged. Impeller clearance excessive. Impeller or volute case damaged. Lift head too high. Pump RPM too low. Suction/discharge hoses too long. Suction head too great. Noise or vibration Mounting bolts loose. Strainer clogged or damaged. Suction head too high. Suction hose too long. Suction hose collapsed. Debris inside pump. Check coupling for proper gasket. Tighten parts. Clean out. Replace. Replace (page 10-6). Replace worn or damaged parts. Adjust (page 3-11). Replace (page 10-3). Reduce discharge head. Move throttle lever fast position. Check throttle lever adjustment (page 7-4). Correct. Move pump closer to water source. Tighten mounting bolts. Clean or replace. Correct. Correct. Replace with proper reinforced hose. Disassemble, inspect, and remove debris. 4-6 dummytext TOP COVER REMOVAL/INSTALLATION ····················· 5-2 5. COVER 5 5-1 dummyhead COVER TOP COVERCOVER REMOVAL/INSTALLATION TOP COVER BOLT TOP COVER 5-2 dummytext 6. FUEL SYSTEM FUEL TANK REMOVAL/INSTALLATION ····················· 6-2 AIR CLEANER REMOVAL/INSTALLATION ····················· 6-3 6 CARBURETOR REMOVAL/INSTALLATION ····················· 6-4 CARBURETOR DISASSEMBLY/ASSEMBLY···················· 6-5 METERING LEVER ADJUSTMENT··········· 6-6 6-1 dummyhead FUEL SYSTEM FUEL TANKFUELSYSTEM REMOVAL/INSTALLATION Gasoline is highly flammable and explosive. You can be burned or seriously injured when handling fuel. · Keep heat, sparks, and flame away. · Handle fuel only outdoors. · Wipe up spills immediately. Remove the recoil starter (page 9-2). Remove the engine from engine bed (page 11-2). Drain the fuel completely from fuel tank and fuel tube. FUEL FEED TUBE (C type) CHECK: Check for deterioration, cracks or clogs. TUBE CLAMP (A type) TUBE CLIP (C type) FUEL RETURN TUBE CHECK: Check for deterioration, cracks or clogs. FUEL FEED TUBE (A type) CHECK: Check for deterioration, cracks or clogs. TUBE CLAMP (A type) FUEL TUBE GROMMET INSTALLATION: Install the fuel return tube [1] into the grommet [2] to the dimensions shown. INSPECTION: Inspect the grommet for deterioration or cracks. TUBE CLIP TUBE CLIP (C type) FUEL TUBE CHECK: Check for deterioration, cracks or clogs. FUEL FILTER CHECK: Check the clogs or damage. TUBE CLIP 103 ± 3 mm (4.1 ± 0.1 in) [2] FUEL TANK CAP [1] 6-2 FUEL TANK TANK MOUNTING RUBBER (3) dummyhead AIR CLEANER REMOVAL/INSTALLATION FUEL SYSTEM COLLAR (2) AIR CLEANER ELEMENT CLEANING: page 3-5 AIR CLEANER CASE INSTALLATION: Before installation, clean inside the case with compressed air. AIR CLEANER COVER NUT (5 mm)(2) BREATHER TUBE INSTALLATION: Before installing the breather line check for deterioration or damage. Replace if necessary. SHORT OIL TRAP PLATE AIR CLEANER CASE SIDE CYLINDER BARREL SIDE LONG 6-3 dummyhead FUEL SYSTEM CARBURETOR REMOVAL/INSTALLATION Gasoline is highly flammable and explosive. You can be burned or seriously injured when handling fuel. · Keep heat, sparks, and flame away. · Handle fuel only outdoors. · Wipe up spills immediately. Remove the air cleaner (page 6-3). INSULATOR PACKING INSULATOR INSTALLATION: Install the insulator with the groove facing toward the carburetor. O-RING (14.8 x 2.4 mm) TUBE CLIP (C TYPE) TUBE CLAMP (A TYPE) CARBURETOR 6-4 CARBURETOR PACKING dummyhead CARBURETOR DISASSEMBLY/ASSEMBLY FUEL SYSTEM Gasoline is highly flammable and explosive. You can be burned or seriously injured when handling fuel. · Keep heat, sparks, and flame away. · Handle fuel only outdoors. · Wipe up spills immediately. Tampering is a violation of Federal and California law. Remove the carburetor (page 6-4). Before disassembly, clean the outside of the carburetor. CARBURETOR BODY ASSEMBLY: Before assembling, clean thoroughly with lowpressure compressed air. SCREW (2) PUMP DIAPHRAGM CHECK: Replace if necessary. PUMP SPRING SWIVEL THROTTLE BODY O-RING MAIN JET ASSEMBLY: Before assembling, clean thoroughly with lowpressure compressed air. METERING DIAPHRAGM GASKET METERING DIAPHRAGM CHECK: Replace if necessary. AIR PURGE BODY PRIMER BULB CHECK: Replace if necessary. PUMP GASKET INLET SCREEN ASSEMBLY: Remove dust and other foreign material from the screen before assembly. METERING LEVER SPRING INLET NEEDLE VALVE ASSEMBLY: Check for worn valve seat [1], valve or weak spring before assembly. PRIMER BULB COVER METERING LEVER [1] REPLACE OK BULB COVER SCREW (4) ASSEMBLY: After assembly, check for any sign of fuel leakage. PUMP BODY ASSEMBLY: Wash the passage with nonflammable solvent to remove dust and other foreign material before assembly. Do not clean by blowing air. METERING LEVER PIN METERING LEVER PIN SCREW 6-5 dummyhead FUEL SYSTEM METERING LEVER ADJUSTMENT Install the metering lever spring [1], inlet needle valve [2], metering lever [3], metering lever pin [4] and [1] metering lever pin screw on the pump body [5]. Measure the gap between the metering lever surface and the pump body surface. METERING LEVER HEIGHT: 1.18 r 1.50 mm (0.046 - 0.059 in) If the measurement is outside the specification, adjust by bending the metering lever. [3] [2] [5] 1.18 - 1.50 mm (0.046 - 0.059 in) [4] 6-6 dummytext 7. CONTROL SYSTEM CONTROL BASE/ENGINE STOP SWITCH REMOVAL/INSTALLATION ····················· 7-2 ENGINE STOP SWITCH INSPECTION ······ 7-3 7 THROTTLE LEVER ADJUSTMENT··········· 7-4 7-1 dummyhead CONTROL SYSTEM CONTROL BASE/ENGINE CONTROLSYSTEM STOP SWITCH REMOVAL/INSTALLATION Remove the air cleaner (page 6-3). THROTTLE ROD INSTALLATION: Install the end of the throttle rod [1] into round hole [2] side of the carburetor. ADJUSTING SCREW SPRING CONTROL LEVER SCREW (5 x 25 mm) CONTROL LEVER SPACER SOCKET BOLT (5 x 10 mm) [1] [2] CORD CLIP NUT (6 mm) ENGINE STOP SWITCH CONTROL LEVER WASHER LEVER SPRING INSTALLATION: Note the installation direction. CONTROL BASE SOCKET BOLT (5 x 16 mm) INSTALLATION: Clean the socket bolt threads and apply thread lock (ThreeBond® #1322N, Hondalock 2 or equivalent) to the threads. 7-2 dummyhead ENGINE STOP SWITCH REMOVAL/INSTALLATION REMOVAL Raise the tab [1] with a screwdriver, and remove the engine stop switch [2]. CONTROL SYSTEM [1] [2] INSTALLATION Align the projection [1] on the control base [2] with the groove [3] in the engine stop switch [4]. [3] Bend the tab as shown. [2] [4] [1] ENGINE STOP SWITCH INSPECTION Remove the engine stop switch connector [1]. Check the continuity between the terminals at each switch position. Switch position ON OFF Continuity No Yes If the correct continuity is not obtained, replace the engine stop switch (page 7-2). [1] 7-3 dummyhead CONTROL SYSTEM THROTTLE LEVER ADJUSTMENT Remove the air cleaner cover (page 6-3). [2] Move the throttle lever [1] slowly by pushing it down to the "HIGH SPEED" side until it brings the carburetor [1] throttle valve [2] to the position where the clearance at the stopper [3] is 0.5 - 1.0 mm (0.02 - 0.04 in). Check that the adjusting screw [4] end is in contact with the stopper or the throttle lever. If it is not, adjust by turning the adjusting screw. [3] [4] 7-4 dummytext 8. IGNITION SYSTEM TOOLS ················································ 8-2 SYSTEM DIAGRAM ······························· 8-3 IGNITION SYSTEM TROUBLESHOOTING ···························· 8-3 IGNITION COIL REMOVAL/INSTALLATION ····················· 8-4 FAN COVER/ENGINE P.T.O.SHAFT/ FLYWHEEL REMOVAL/INSTALLATION···· 8-5 IGNITION COIL AIR GAP CHECK/ADJUSTMENT··························· 8-7 8 SPARK TEST········································ 8-8 IGNITION COIL INSPECTION ·················· 8-8 ENGINE P.T.O.SHAFT INSPECTION········· 8-9 RADIAL BALL BEARING (6001) REPLACEMENT ···································· 8-9 8-1 dummyhead IGNITION SYSTEM TOOLS IGNITION SYSTEM Pilot, 12 mm 07746-0040200 Driver 07749-0010000 Attachment, 28 x 30 mm 07946-1870100 8-2 dummyhead SYSTEM DIAGRAM Bl IGNITION SYSTEM Bl SPARK PLUG IGNITION COIL ENGINE STOP SWITCH ENGINE STOP SWITCH IG E OFF ON Bl Black Y Yellow Bu Blue G Green R Red W White Br Brown O Orange Lb Light blue Lg Light green P Pink Gr Gray IGNITION SYSTEM TROUBLESHOOTING NO OR WEAK SPARK AT SPARK PLUG Check the following before troubleshooting: Loose connectors Spark plug (page 3-6) Check the engine stop switch (page 7-3). Normal Check the ignition coil (page 8-8). Normal Check for continuity between the engine stop switch cord connectors.Replace if necessary. Abnormal Abnormal Replace the engine stop switch (page 7-2). Replace the ignition coil (page 8-4). 8-3 dummyhead IGNITION SYSTEM IGNITION COIL REMOVAL/INSTALLATION Remove the top cover (page 5-2). · Route the engine wire harness and high-tension code properly (page 2-6). · After installation, check the ignition coil air gap (page 8-7). HIGH TENSION CORD SOCKET BOLT (4 x 14 mm) 3.9 N·m (0.40 kgf·m, 2.9 lbf·ft) 8-4 IGNITION COIL dummyhead FAN COVER/ENGINE P.T.O. SHAFT/ FLYWHEEL REMOVAL/INSTALLATION Remove the ignition coil (page 8-4). Remove the casing cover (page 10-5). IGNITION SYSTEM NUT (7 mm) (Threads and seating surface) 14.7 N·m (1.5 kgf·m, 11 lbf·ft) ENGINE P.T.O. SHAFT RADIAL BALL BEARING(6001) (Rolling surface) FLYWHEEL SOCKET BOLT (5 x 20 mm) (3) 6.4 N·m (0.65 kgf·m, 4.7 lbf·ft) FAN COVER BOLT (6 x 22 mm) (2) 8-5 dummyhead IGNITION SYSTEM ENGINE P.T.O. SHAFT REMOVAL/INSTALLATION · To avoid flywheel fan blade damage, position the strap wrench fulcrum at the flywheel magnetic parts. Holding the flywheel [1] with a commercially available [4] strap wrench [2], remove the bolt (6 x 22 mm) [3] and remove the P.T.O. shaft [4]. [3] Installation is in the reverse order of removal. [2] [1] FLYWHEEL REMOVAL/INSTALLATION REMOVAL · To avoid flywheel fan blade damage, position the strap wrench fulcrum at the flywheel magnetic parts. Remove the engine P.T.O.shaft (page 8-6). Holding the flywheel [1] with a commercially available strap wrench [2], remove the nut (7 mm) [3] from the [2] flywheel. Remove the flywheel [1] using a commercially available flywheel puller [2]. · Do not remove the flywheel by tapping it with a hammer. [1] [3] [2] [1] 8-6 dummyhead INSTALLATION · Clean the tapered part of dirt, oil, grease and other foreign material before installation. · Be sure that there is no washer or other foreign material on the magnetic part. Be sure that the woodruff key is set in the key groove properly. Holding the flywheel [1] with a commercially available strap wrench [2], tighten the nut (7 mm) [3] to the specified torque. TORQUE: 14.7 N·m (1.5 kgf·m, 11 lbf·ft) Install the engine P.T.O. shaft (page 8-6). IGNITION SYSTEM [3] [2] [1] IGNITION COIL AIR GAP CHECK/ADJUSTMENT Remove the top cover (page 5-2). Insert the feeler gauge [1] of proper thickness between the ignition coil [2] and the flywheel [3]. [3] · Check the clearance at the magnet part of the flywheel. IGNITION COIL AIR GAP: 0.2 0.4 mm (0.01 0.02 in) [2] [1] If measured clearance is out of specification, adjust the air gap. [1] Loosen the two socket bolts (4 x 14 mm) [1]. Insert the feeler gauge of proper thickness between the ignition coil [2] and magnet part [3] of the flywheel. [2] Push the ignition coil firmly against the magnet part of the flywheel and tighten the two socket bolts (4 x 14 mm) to the specified torque. Remove the feeler gauge. TORQUE: 3.9 N·m (0.40 kgf·m, 2.9 lbf·ft) Install the top cover (page 5-2). [3] 8-7 dummyhead IGNITION SYSTEM SPARK TEST Check for the following before conducting the spark test. [1] [2] · Faulty spark plug · Loose spark plug cap · Water in the spark plug cap (leaking the ignition coil secondary voltage) · Loose ignition coil connector Disconnect the spark plug cap [1] from the spark plug [2]. Connect a known-good spark plug [3] to the spark plug cap and ground the spark plug to the air exhaust guide[4]. Turn the engine stop switch to "ON" position. Crank the engine by pulling the recoil starter and check whether sparks jump across the electrodes. [4] IGNITION COIL INSPECTION Remove the top cover (page 5-2). PRIMARY SIDE Disconnect the ignition coil connector [1]. Measure the resistance of the primary coil by attaching [1] one ohmmeter probe to the ignition coil connector and the other at the iron core [2]. RESISTANCE: 0.585 r 0.715 If measured resistance is out of specification, replace the ignition coil. SECONDARY SIDE Measure the resistance of the secondary coil by attaching one ohmmeter probe to the spark plug cap [1] and the other at the iron core [2]. RESISTANCE: 4.77 r 5.83 k If measured resistance is out of specification, replace the ignition coil. [1] [3] [2] [2] 8-8 dummyhead ENGINE P.T.O. SHAFT INSPECTION Measure the engine P.T.O.shaft [1] bearing O.D. STANDARD: 11.966 r 11.984 mm (0.4711 r 0.4718 in) SERVICE LIMIT: 11.800 mm (0.4646 in) [1] If the measurement is less than the service limit, replace the engine P.T.O. shaft and fan cover bearing (6001) as a set (page 8-9). IGNITION SYSTEM RADIAL BALL BEARING (6001) REPLACEMENT INSTALLATION Apply oil to the inner surface and the outer surface of a new radial ball bearing [1]. Press the radial ball bearing in the fan cover [2] using the special tools. TOOLS: Attachment, 28 x 30 mm [3] Pilot, 12 mm [4] Driver [5] 07946-1870100 07746-0040200 07749-0010000 [5] [4] [2] [3] [1] 8-9 dummyhead MEMO dummytext 9. STARTING SYSTEM RECOIL STARTER REMOVAL/INSTALLATION ····················· 9-2 STARTER PULLEY REMOVAL/INSTALLATION ····················· 9-3 RECOIL STARTER DISASSEMBLY/ASSEMBLY···················· 9-4 9 9-1 dummyhead STARTING SYSTEM RECOIL STARTER STARTINGSYSTEM REMOVAL/INSTALLATION Remove the top cover (page 5-2). RECOIL STARTER 9-2 SOCKET BOLT (5 x 16 mm) dummyhead STARTER PULLEY REMOVAL/INSTALLATION Remove the recoil starter (page 9-2). Remove the fuel tank (page 6-2). STARTING SYSTEM STARTER PULLEY REMOVAL: Holding the flywheel [1] with commercially available strap wrench [2], remove the recoil starter pulley [3] with a driver or equivalent tool [2] [4] [3] [1] INSTALLATION: Holding the recoil starter pulley [1] in the same manner as on disassembly, tighten the flywheel [2] to the specified torque. 14.7 N·m (1.5 kgf·m, 11 lbf·ft) [2] [1] 9-3 dummyhead STARTING SYSTEM RECOIL STARTER DISASSEMBLY/ASSEMBLY The recoil spring is wound under high tension and when released from the groove will cause sudden unwinding. Sudden unwinding can cause severe lacerations. Wear gloves and eye protection during this procedure and take care not to allow the spring to come out. DISASSEMBLY Remove the recoil starter (page 9-2). SET SCREW SWING ARM COLLOR RECOIL STARTER ROPE SWING ARM RECOIL STARTER REEL STARTER GRIP RECOIL STARTER CASE (Recoil starter reel sliding area) 9-4 RECOIL STARTER SPRING (Recoil starter reel sliding area) dummyhead ASSEMBLY Insert the hook on the outer side of the spring [1] into the groove [2] inside the starter reel [3]. Carefully wind [4] the recoil starter spring [4] inside the starter reel. STARTING SYSTEM [1] [3] [2] Pass the starter rope [1] through the starter reel [2] and tie the rope so that it can be untied easily by pulling it as [1] shown. Wind the starter rope around the recoil starter reel in the direction of the arrow. Position the end of the starter rope [1] at the cutout [2] in the starter reel [3]. [1] [3] Install the starter reel [1] on the starter case [2] so that the spring [3] inner hook [4] is hooked to the case tab [1] [5]. [5] [2] [2] [4] [3] [2] 9-5 dummyhead STARTING SYSTEM Secure the starter reel [1] with the set screw [2]. [2] · Make sure to align the groove [3] of the swing arm collar [4] with the swing arm [5]. [4] [3] Hold the starter case [1] and rotate the starter reel [2] three turns in the direction of the arrow for preliminary winding. [1] [5] [2] [1] Pass the starter rope [1] end through the case [2] and pull it outwards. Pass the starter rope through the starter grip [3] and tie the rope so that it can be untied easily by pulling it as shown. Pull the starter grip several time to make sure the swing arm [4] operates properly. [3] [1] [2] [4] 9-6 dummytext 10. PUMP TOOLS ·············································· 10-2 INLET PIPE/OUTLET PIPE REMOVAL/INSTALLATION ··················· 10-3 CASING/VOLUTE CASE REMOVAL/INSTALLATION ··················· 10-4 IMPELLER/CASING COVER REMOVAL/INSTALLATION ··················· 10-5 MECHANICAL SEAL REPLACEMENT ···· 10-6 10 10-1 dummyhead PUMP TOOLS PUMP Attachment, 24 x 26 mm 07746-0010700 Driver 07749-0010000 Mechanical seal installer 07965-415000A 10-2 dummyhead INLET PIPE/OUTLET PIPE REMOVAL/INSTALLATION FILLER CAP SERVICE BULLETIN #9 PUMP O-RING (23.7 x 3.5 mm) BOLT (6 x 20 mm) (4) OUTLET PIPE INSTALLATION: Install in desired position. Three options to choose from. OUTLET PACKING INLET PIPE BOLT (6 x 20 mm) (3) INLET VALVE INSTALLATION: Check the inlet valve for breakage or excessive wear damage. Align the tab [1] on the inlet valve with the groove [2] of the inlet pipe. ALIGN [1] [2] 10-3 dummyhead PUMP CASING/VOLUTE CASE REMOVAL/INSTALLATION VOLUTE CASE INSTALLATION: Check the mating surface for damage and nicks. INSPECTION: Inspect the inside for excessive wear or damage. O-RING (140 x 3.5 mm) O-RING (36.5 x 5.7 mm) CASING O-RING (23.7 x 3.5 mm) SERVICE BULLETIN #9 10-4 BOLT (6 x 25 mm) (4) TORQUE: Tighten in a diagonal pattern in multiple steps to the proper torque. DRAIN CAP dummyhead IMPELLER/CASING COVER REMOVAL/INSTALLATION Remove the engine and pump from engine bed (page 11-2). Remove the volute case (page 10-4). Remove the ignition coil (page 8-4). CASING COVER ALUMINUM SEALING WASHER (5 mm) (4) PUMP SOCKET BOLT (5 x 35 mm) (4) 5.0 N·m (0.51 kgf·m, 3.7 lbf·ft) ADJUSTER SHIM RUBBER RING /CERAMIC RING REMOVAL: Insert a rod of O.D. 8 - 10 mm (0.30 - 0.40 in) [1] between the flywheel [2] weight [3] and fan cover [4] and lock the flywheel as shown. Holding flywheel locked, remove the impeller. [1] INSTALLATION: Insert a rod of O.D. 5 - 6 mm (0.20 - 0.24 in) [1] into the gap in the cylinder barrel [2], and lock the flywheel [3] by setting the rod on the flywheel weight [4] and on the projection [5] on the cylinder barrel as shown. Holding flywheel locked, tighten the impeller to the specified torque. 6.9 N·m (0.70 kgf·m, 5.1 lbf·ft) INSPECTION: Inspect the impeller vanes for excessive wear or damage. Replace if necessary. After installation, check the impeller clearance: (page 3-11) [1] [2] [4] [2] [5] [3] [3] [4] 10-5 dummyhead PUMP MECHANICAL SEAL REPLACEMENT Drive out the mechanical seal [1] from the inside using the special tools. TOOLS: Driver handle [2] Attachment, 24 x 26 mm [3] 07749-0010000 07746-0010700 Place the seal onto the seal driver [1] and bolt [2]. Put the bolt through the casing cover [3]. Install the back up plate [4] with the B side facing the casing cover and install the washer [5] and nut [6]. Tighten until the seal is fully seated. [1] [1] · Be careful not to damage the sliding surface of the [3] mechanical seal. TOOLS: Mechanical seal installer 07965-415000A After installing, check to be sure the seal is fully seated and is not tilted in the casing cover. Install a new rubber ring [1] over a new ceramic ring [2]. · Be careful not to damage the sliding surface of the ceramic ring. Apply soapy water around the rubber ring. Install the rubber ring/ceramic ring assembly into the impeller [3] carefully with the rubber ring facing the impeller until it is fully seated. [5] [2] [3] [2] [3] [2] [4] [6] [1] 10-6 dummytext 11. ENGINE REMOVAL/INSTALLATION ENGINE REMOVAL/INSTALLATION······· 11-2 11 11-1 dummyhead ENGINE REMOVAL/INSTALLATION ENGINE REMOVAL/INSTALLATION ENGINEREMOVAL/INSTALLATION BOLT (6 x 14 mm) (2) HANDLE FRAME BED NUT (6 mm) (4) 11-2 BOLT (6 x 14 mm) (2) BOTTOM RUBBER (4) INSTALLATION: Check for cracking, deformation or other damage before installation. Install by aligning with the hole in the frame. SCREW (6 x 10 mm) (4) dummytext 12. CRANKCASE TOOLS ·············································· 12-2 LOWER CRANKCASE/SHROUD REMOVAL/INSTALLATION ··················· 12-3 CRANKSHAFT/PISTON REMOVAL/INSTALLATION ··················· 12-6 CRANKSHAFT/PISTON INSPECTION···· 12-10 12 12-1 dummyhead CRANKCASE TOOLS CRANKCASE Piston base 07VPF-ZM3010B Push rod 07VPF-ZM3020A Guide 07VPF-ZM3030A 12-2 dummyhead LOWER CRANKCASE/SHROUD REMOVAL/INSTALLATION Drain the engine oil (page 3-4). Remove the engine (page 11-2). Remove the following: Control base (page 7-2) Carburetor (page 6-4) Fuel tank (page 6-2) Muffler (page 14-2) Flywheel (page 8-6) Starter pulley (page 9-3) CRANKCASE BOLT (5 x 58 mm) (2) O-RING (12.3 x 2.4 mm) SHROUD SCREW (4 x 8 mm) (2) 3.0 N·m (0.31 kgf·m, 2.2 lbf·ft) OIL OUTLET VALVE PLATE OIL FILLER CAP OIL FILLER CAP PACKING SOCKET BOLT (5 x 30 mm) (4) 6.4 N·m (0.65 kgf·m, 4.7 lbf·ft) TUBE CLIP (D12) SPRING PIN (4 x 10 mm) SOCKET BOLT (5 x 16 mm) (2) INSTALLATION: Clean the socket bolt threads and apply thread lock (ThreeBond® #1322N, Hondalock 2 or equivalent) to the threads. OIL TUBE INSTALLATION: Inspect for cracks or deterioration before installation. TUBE CLIP (D13) LOWER CRANKCASE SOCKET BOLT (5 x 20 mm) (2) 6.4 N·m (0.65 kgf·m, 4.7 lbf·ft) 12-3 dummyhead CRANKCASE LOWER CRANKCASE REMOVAL/INSTALLATION REMOVAL Remove the two socket bolts (5 x 20 mm) and four socket bolts (5 x 30 mm). CARBURETOR SIDE: Insert the screw driver or equivalent tool into the recess [1] as shown, and remove the lower crankcase from the cylinder barrel. MUFFLER SIDE: INSTALLATION Clean the inside of the crankcase and remove foreign material. Clean the mating surfaces of the cylinder barrel and the lower crankcase [1] using a degreasing cleaning agent and clean shop towel. Apply a bead [2] [1.0 1.5 mm (0.04 0.06 in)] of the liquid sealant (ThreeBond® 1216E, Hondabond HT or equivalent) to the mating surface with the lower crankcase. Install the lower crankcase on the cylinder barrel. Assemble within 3 minutes after applying the liquid gasket. Loosely tighten each two socket bolts (5 x 20 mm) and four socket bolts (5 x 30 mm) then tighten to the numbered sequence. TORQUE: 6.4 N·m (0.65 kgf·m, 4.7 lbf·ft) Wait for approximately 60 minutes after assembly before filling oil and starting the engine. [1] [1] [1] [2] 5 1 3 2 6 4 12-4 dummyhead SHROUD INSTALLATION Set the two bolts (5 x 58 mm) [1] on the shroud [2]. Take care not to allow the bolt heads to protrude from [2] the shroud when installing on the cylinder barrel. CRANKCASE OIL TUBE INSTALLATION Install the oil tube and the tube clamp (D12) [1] and tube clamp (D13) [2] with the " UP" mark [3] of the oil tube facing toward the cylinder. · Do not interchange the clamps. · Be sure that the tube and the shroud do not come into contact. [3] [1] [1] [2] 12-5 dummyhead CRANKCASE CRANKSHAFT/PISTON REMOVAL/INSTALLATION Remove the lower crankcase (page 12-3). Remove the cam pulley (page 13-4). PISTON RING INSTALLATION: ·Install the top ring and second ring with the""mark facing up. ·Do not interchange the top ring and the second ring. ·After assembly, check for smooth movement of the piston ring. ·Stagger the piston ring end gaps 120° apart. Do not align with the piston pin. ·Space the side rail end gaps at least 10 mm (0.4 in) apart. Coat the oil ring with oil after assembly. TOP RING SECOND RING OIL RING (COMBINATION RING) SIDE RAIL SPACER SIDE RAIL ""MARK TOP RING MUFFLER SIDE: TIMING BELT INSTALLATION: Check that the belt is not worn or cracked. Do not bend or twist the belt. CARBURETOR SIDE: 120° 120° 120° SECOND RING 10 mm (0.4 in) OIL RING (COMBINATION RING) 10 mm (0.4 in) " " MARK PISTON (Outer surface) INSTALLATION: Install with the " " on the piston head facing the carburetor side. 12-6 PISTON PIN (Outer surface) OIL SEAL (12 x 24 x 5 mm) (Apply to the lip) OIL SEAL (10 x 20 x 5 mm) (Apply to the lip) CRANKSHAFT (Bearing rolling surface) dummyhead PISTON PIN REMOVAL/ INSTALLATION REMOVAL Insert the special tool (push rod) into the piston pin with the crankshaft timing belt drive pulley [1] upward as shown. TOOL: Push rod [2] 07VPF-ZM3020A [2] CRANKCASE [1] Set the cutout part [1] of the special tool (piston base) in the clearance [2] between the connecting rod [3] and the piston as shown. · Be sure that the connecting rod small end is securely set in the cutout of the special tool (piston base). TOOL: Piston base [4] Push rod [5] 07VPF-ZM3010B 07VPF-ZM3020A Remove the piston pin [6] from the connecting rod using a hydraulic press. Approx. gap: 1.5 mm (0.060 in) [1] [5] [6] [3] [2] [4] 12-7 dummyhead CRANKCASE INSTALLATION Slide the piston pin [1] over the special tool (push rod) and install the special tool (guide). TOOL: Push rod [2] Guide [3] 07VPF-ZM3020A [2] 07VPF-ZM3030A Set the piston over the connecting rod so that the crankshaft oil slinger [1] comes at the right side with the " " mark [2] on the piston head toward you as shown. [1] [3] [2] [1] Apply oil to the piston pin [1] and assemble the piston pin with special tools attached as shown. With the timing belt drive pulley [2] up, align the piston pin hole with the connecting rod [3] hole and insert the [1] special tool (guide) into the piston pin hole. Set the cutout part [4] of the special tool (piston base) in the clearance between the connecting rod and the piston as shown. · Be sure that the connecting rod small end is securely set in the cutout of the special tool (piston base). TOOL: Piston base [5] Push rod [6] Guide [7] 07VPF-ZM3010B 07VPF-ZM3020A 07VPF-ZM3030A [1] [4] Using a hydraulic press to press the piston pin into the connecting rod until the piston pin extends approximately 1.5 mm (0.060 in) above the piston pin. Remove the special tools from the piston pin. [2] [6] [3] [7] [5] Approx. gap: 1.5 mm (0.060 in) 12-8 dummyhead After assembling the piston pin [1], move the connecting rod [2] from side-to-side and make sure the gap from the piston pin end to the piston [3] end is equal at the right and left sides. If the right and left gaps are not equal, raise or lower piston pin as needed. Approx. gap: 1.5 mm (0.060 in) CRANKCASE Approx. gap: 1.5 mm [3] (0.060 in) [1] [2] CRANKSHAFT INSTALLATION Install the timing belt [1] on the timing gear [2] of the crankshaft. When installing, pay attention to the direction of the letter [3] on the timing belt as shown in [6] the picture. · Replace worn or cracked timing belt. Do not bend or twist the timing belt. Install the crankshaft [4] in the cylinder barrel [5]. Apply a bead of Hondabond HT liquid gasket to the [5] cylinder barrel (page 12-4) specifically to the mating surface of the lower crankcase. Install the lower crankcase on the cylinder barrel. [1] Install the cam pulley [6] and timing belt in the cylinder barrel (page 13-4). [3] CRANKSHAFT OIL SEAL (10 x 20 x 5 mm/12 x 24 x 5 mm) INSTALLATION Apply grease to the lip of the oil seal [1]. Set the oil seal on the crankshaft [2]. Install crankshaft by aligning the oil seal projection [3] [1] with the groove [4] in the cylinder barrel. Install the lower crankcase (page 12-4). [2] [3] [4] [4] [2] 12-9 dummyhead CRANKCASE CRANKSHAFT/PISTON INSPECTION OIL SLINGER Check the oil slinger [1] of the crankshaft for damage and deformation. Replace the crankshaft if it is damaged or deformed. [1] CYLINDER SLEEVE I.D. Measure and record the cylinder I.D. at three levels in both the "X" axis (perpendicular to crankshaft) and the "Y" axis (parallel to crankshaft). Take the maximum reading to determine cylinder wear and taper. X STANDARD: 35.000 35.015 mm (1.3780 1.3785 in) TOP Y SERVICE LIMIT: 35.100 mm (1.3819 in) MIDDLE If the measurement is more than the service limit, replace the crankcase set, piston, and rings. BOTTOM PISTON SKIRT O.D. Measure and record the piston O.D. at a point 10 mm (0.4 in) from the bottom of the skirt and 90 degrees to the piston pin bore. STANDARD: 34.970 34.990 mm (1.3768 1.3776 in) SERVICE LIMIT: 34.900 mm (1.3740 in) If the measurement is less than the service limit, replace the piston and rings. Do not hone the cylinder. 90° 10 mm (0.4 in) PISTON-TO-CYLINDER CLEARANCE Subtract the piston skirt O.D. from the cylinder sleeve I.D. to obtain the piston-to-cylinder clearance. STANDARD: 0.010 0.045 mm (0.0004 0.0018 in) SERVICE LIMIT: 0.120 mm (0.0047 in) If the calculated clearance is more than the service limit, replace the piston and recheck the clearance. If the clearance is still more than the service limit with the new piston, replace the crankcase set. Do not hone the cylinder. 12-10 dummyhead PISTON PIN BORE I.D. Measure and record the piston pin bore I.D. of the piston. STANDARD: 8.010 8.026 mm (0.3154 0.3160 in) SERVICE LIMIT: 8.060 mm (0.3173 in) If the measurement is more than the service limit, replace the piston. PISTON PIN O.D. Measure and record the piston pin O.D. at three points (both ends and middle). Take the minimum reading to determine piston pin O.D. STANDARD: 7.994 8.000 mm (0.3147 0.3150 in) SERVICE LIMIT: 7.950 mm (0.3130 in) If the measurement is less than the service limit, replace the piston pin. PISTON PIN-TO-PISTON PIN BORE CLEARANCE Subtract the piston pin O.D. from the piston pin bore I.D. to obtain the piston pin-to-piston pin bore clearance. STANDARD: 0.010 0.032 mm (0.0004 0.0013 in) SERVICE LIMIT: 0.070 mm (0.0028 in) If the calculated clearance is more than the service limit, replace the piston pin and recheck the clearance. If the clearance is still more than the service limit with the new piston pin, replace the piston. PISTON RING SIDE CLEARANCE Measure the clearance between each piston ring and ring groove of the piston using feeler gauge. STANDARD: Top/Second: SERVICE LIMIT: Top/Second: 0.015 0.056 mm (0.0006 0.0022 in) 0.120 mm (0.0047 in) If the calculated clearance is more than the service limit, replace the piston rings (top, second, oil) as a set and recheck the clearance. If the clearance is still more than the service limit with the new piston ring, replace the piston. CRANKCASE 12-11 dummyhead CRANKCASE PISTON RING WIDTH Measure each piston ring width. STANDARD: Top/Second: SERVICE LIMIT: Top/Second: 0.970 0.990 mm (0.0382 0.0390 in) 0.920 mm (0.0362 in) If any of the measurements is less than the service limit, replace the piston rings (top, second, oil) as a set. Do not hone the cylinder. PISTON RING END GAP Before inspection, check whether the cylinder sleeve I.D. is within the specification (page 12-10). Put the piston ring in the cylinder and then use the piston crown to push the ring down. This will make the piston ring horizontal so ring end gap can be measured. Measure each piston ring [1] end gap using a feeler gauge. STANDARD: Top/Second: 0.10 0.25 mm (0.004 0.010 in) SERVICE LIMIT: Top/Second: 0.60 mm (0.024 in) [1] If any of the measurements is more than the service limit, replace the piston rings (top, second, oil) as a set. Do not hone the cylinder. CONNECTING ROD SMALL END I.D. Measure the connecting rod small end I.D. STANDARD: SERVICE LIMIT: 7.978 7.989 mm (0.3141 0.3145 in) Replace if exceeding the standard value. If the measurement is more than the service limit, replace the crankshaft. 12-12 dummytext 13. CYLINDER HEAD TOOL················································· 13-2 CYLINDER HEAD COVER/CAM PULLEY REMOVAL/INSTALLATION ··················· 13-3 ROCKER ARM/VALVES REMOVAL/INSTALLATION ··················· 13-5 CYLINDER COMPRESSION CHECK······ 13-10 CYLINDER HEAD/VALVES INSPECTION ····································· 13-10 13 13-1 dummyhead CYLINDER HEAD TOOL CYLINDER HEAD Rocker arm replacement tool 070PF-Z0HA100 13-2 dummyhead CYLINDER HEAD COVER/CAM PULLEY REMOVAL/INSTALLATION Remove the following: Spark plug (page 3-6) Top cover (page 5-2) Fan cover (page 8-5) CYLINDER HEAD BREATHER TUBE SOCKET BOLT (5 x 12 mm) (2) HEAD COVER BREATHER FILTER HEAD COVER SEAL SCREW (4 x 12 mm) (2) HEAD COVER GROMMET CAM PULLEY INSPECTION: (page 13-11) (Profile and journal) CAM PULLEY SHAFT (Whole surface) HEAD INNER COVER TIMING BELT INSTALLATION: Check that the belt is not worn or cracked. Do not bend or twist the belt. 13-3 dummyhead CYLINDER HEAD CAM PULLEY REMOVAL/ INSTALLATION Remove the following: Spark plug (page 3-6) Head cover (page 13-3) Fan cover (page 8-5) Set the piston at top dead center (TDC) of the compression stroke. When the piston is at TDC of the compression stroke, the flywheel " " mark [1] will align with the fan cover bolt hole [2]. Also, the cam pulley alignment marks [3] will be positioned as shown. [2] [1] [3] Push the cam pulley shaft [1] out from the valve spring side using a pin approximately 2 mm in diameter. · Be careful not to let the cam pulley shaft fall into the crankcase. [1] Remove the timing belt [1] from the cam pulley [2], and remove the cam pulley. [2] Installation is in the reverse order of removal. Make [1] sure the alignment marks on the cam pulley and the flywheel are aligned. 13-4 dummyhead ROCKER ARM/VALVES REMOVAL/INSTALLATION Remove the cam pulley (page 13-3). Remove the crankshaft (page 12-6). VALVE SPRING RETAINER (2) REMOVAL: Push down and slide the retainer to the side, so the valve stem slips through the hole at the slide of the retainer. Do not remove the valve spring retainers while the lower crankcase is installed, or the valves will drop into the cylinder. VALVE SPRING (2) (Whole surface) INTAKE VALVE LIFTER REMOVAL/INSTALLATION: (page 13-6) Do not interchange with the exhaust valve rocker arm. Do not reuse after removing. ViDewo endotfrroemusreecoil stafrter rseidmeo.ving. VALVE STEM SEAL (Intake valve only) EXHAUST VALVE LIFTER REMOVAL/INSTALLATION: (page 13-6) Do not interchange with the intake valve rocker arm. Do not reuse after removing. Viewed from recoil starter side. INTAKE VALVE (Sliding surface) INSTALLATION: Do not interchange with the exhaust valve. CYLINDER HEAD INTAKE VALVE ROCKER ARM REMOVAL/INSTALLATION: (page 13-6) Do not interchange with the exhaust valve rocker arm. Do not reuse after removing. Viewed from clutch side. SPARK PLUG 11.8 N·m (1.2 kgf·m, 8.7 lbf·ft) ADJUSTING SCREW (2) ADJUSTING SCREW LOCK NUT (2) 4.9 N·m (0.50 kgf·m, 3.6 lbf·ft) EXHAUST VALVE ROCKER ARM REMOVAL/INSTALLATION: (page 13-6) Do not interchange with the intake valve rocker arm. Do not reuse after removing. Viewed from clutch side. EXHAUST VALVE (Sliding surface) INSTALLATION: Do not interchange with the intake valve. Before installation, remove the carbon deposits and inspect the valve. 13-5 dummyhead CYLINDER HEAD ROCKER ARM/VALVE LIFTER REMOVAL/INSTALLATION REMOVAL Remove the adjusting screw lock nuts [1] and remove the adjusting screws [2] from the rocker arms [3]. [1] Remove the cam pulley (page 13-4). [2] [3] Tighten the holder bolt [1] of the special tool fully as shown. TOOL: Rocker arm replacement tool [2] 070PF-Z0HA100 Set the special tool on the cylinder head over the rocker arm and valve lifter that you are going to take apart, and tighten the bolt (5 mm) [3] to the cylinder head cover installation boss [4] by hand. Do not tighten the bolt (5 mm) using a wrench. Tighten the push rod [1] of the special tool by hand until the tip of the push rod comes to the center of the valve lifter shaft [2]. Move the special tool left and right and check that it can be moved slightly. [2] [3] [1] [4] It should be able to move slightly in this direction. (Or the cylinder head cover installation boss will be damaged) [1] Using a 14 mm wrench [1], tighten the push rod [2] until the shaft of the valve lifter goes out from the rocker arm [3]. [2] Loosen the push rod and remove the bolt (5 mm) [4], and then remove the special tool. The valve lifters and rocker arms cannot be reused after they are pressed apart. Always replace with new parts. [1] 13-6 [2] [4] [3] dummyhead INSTALLATION Install the new valve lifter [1] on the cylinder head and bring the valve lifter in contact with the installation guide rib [2] of the cylinder head. Push the new rocker arm [3] into the shaft of the valve lifter by hand while holding the valve lifter in the position and holding the rocker arm against the installation guide rib [4] of the cylinder head. · Check the valve lifter for inlet side and exhaust side before installation. Do not interchange them. · Check the rocker arm for "IN" or "EX" marks before installation. Do not interchange them. CYLINDER HEAD Viewing cylinder head right down: EXHAUST VALVE LIFTER INTAKE VALVE LIFTER [1] [2] [3] [4] Viewed from the flywheel side: EXHAUST VALVE ROCKER ARM Set the projection [1] of the valve lifter [2] in contact with the installation guide rib [3] of the cylinder head. Set the rocker arm [4] in contact with the installation guide rib [5] of the cylinder head. Check that the projection on the valve lifter and the rocker arm are in contact with the installation guide rib of the cylinder head. INTAKE VALVE ROCKER ARM [4] [5] [2] [1] [3] 13-7 dummyhead CYLINDER HEAD Install the holder bolt [1] of the special tool in the direction as shown. TOOL: Rocker arm replacement tool [2] 070PF-Z0HA100 Install the adapter [3] on the tip of the push rod [4] that is set on the special tool. Install the special tool on the cylinder head so that the bolt (5 mm) [5] sets in the center of the long hole in the special tool as shown. Tighten the bolt (5 mm) against the cylinder head cover mounting boss by hand. [4] · Set the bolt (5 mm) in the center of the long hole. · Do not tighten the bolt (5 mm) using a wrench. [5] [1] [2] [3] Bring the projection on the valve lifter [1] and the rocker arm [2] to come in contact with the cylinder head positioning ribs [3]. Bring the clearance A [4] and B [5] to be equal by moving the valve lifter and rocker arm right and left. While holding the valve lifter and rocker arm in the position, tighten the holder bolt [6] by hand until it contacts the valve lifter. Tighten the push rod [7] by hand until the adapter [8] contacts the rocker arm. After installing the special tool, check that the bolt (5 mm) [9] is in the center of the long hole [10] in the tool. Note that the cylinder head cover mounting boss can be damaged by tightening the push rod with the bolt (5 mm) not in the center but on either side in the long hole. Be sure that the bolt is in the center of the long hole securely. [2] [8] [9] [10] [1] [6] [3] [4] [5] [3] [7] Using a 14 mm wrench [1], tighten the push rod [2] until the rocker arm [3] comes to the cylinder head cover installation part. [4] [2] [3] [1] [4] [3] [2] 13-8 dummyhead Loosen the push rod [1] and tighten the holder bolt [2] by hand until the valve lifter [3] contacts the cylinder head cover mounting boss [4]. Be sure that the bolt (5 mm) [5] is in the center of the long hole in the special tool. Loosen Note that the cylinder head cover mounting boss can be damaged by tighten the push rod with the bolt (5 mm) not in the center but on either side in the long hole. Be sure that the bolt is in the center of the long hole securely. Using a 14 mm wrench, retighten the push rod [1] until the adapter [2] comes to the shaft of the valve lifter [3]. Loosen the push rod and remove the bolt (5 mm) [4], and then remove the special tool. [1] Tighten CYLINDER HEAD [5] [4] Tighten [2] [3] [4] [2] Measure the clearance between the rocker arm and the cylinder head, and make sure if the clearance are within the specification. Rocker arm and cylinder head clearance: 0.15 0.65 mm (0.006 0.026 in) If the clearance is over the specification, the rocker arm is not correctly installed to the valve lifter. Install the special tool again, and tighten the push rod until the rocker arm is completely pressed onto the shaft of the valve lifter. Inject the oil as shown. Lift the lifter by finger and release the lifter, and make sure it operates by the lifter's weight. Install the adjusting screws and the adjusting screw lock nuts to the rocker arms. Install the cam pulley (page 13-4). Adjust the valve clearance (page 3-8). [1] [3] 0.15 mm - 0.65 mm (0.006 - 0.026 in) 13-9 dummyhead CYLINDER HEAD CYLINDER COMPRESSION CHECK Warm the engine to normal operating temperature. [1] Turn the engine stop switch to the OFF position. Make sure the choke is open. Drain the fuel from the fuel tank. Drain the fuel from the carburetor by pushing the carburetor primer pump. Remove the spark plug cap from the spark plug. Remove the spark plug using a spark plug wrench. Pull the recoil starter several times to expel unburned gas. Attach a commercially available compression gauge [1] to the spark plug hole. Open the throttle all the way and pull the recoil starter forcefully until the gauge reading stops rising. CYLINDER COMPRESSION: 0.9 MPa (9.2 kgf/cm2, 130.9 psi) / 2,000 min-1 (rpm) CYLINDER HEAD/VALVES INSPECTION DECOMPRESSOR Move the decompressor arm with your finger. Make sure the decompressor weight [1] operates smoothly. Check that the decompressor moves and automatically returns back to its original position. If the decompressor is faulty, replace the cam pulley as an assembly. [1] CAM HEIGHT Measure the cam height. STANDARD: 21.897 22.297 mm (0.8621 0.8778 in) SERVICE LIMIT: 21.797 mm (0.8581 in) If the measurement is less than the service limit, replace the cam pulley. 13-10 dummyhead CAM PULLEY SHAFT O.D. Measure the cam pulley shaft O.D. at three points (both ends and middle). Take the minimum reading to determine cam pulley shaft O.D. STANDARD: 3.990 4.000 mm (0.1571 0.1575 in) SERVICE LIMIT: 3.950 mm (0.1555 in) If the measurement is less than the service limit, replace the cam pulley shaft. CAM PULLEY I.D. Measure the cam pulley I.D. STANDARD: 4.020 4.050 mm (0.1583 0.1594 in) SERVICE LIMIT: 4.100 mm (0.1614 in) If the measurement is more than the service limit, replace the cam pulley. CYLINDER HEAD CAM PULLEY AND VALVE LIFTER Check for damage or wear of the cam [1], cam pulley and the cam contact section [2] of the valve lifter. [1] If the cam is abnormally worn or damaged, replace the cam pulley and valve lifter. [2] VALVE SPRING FREE LENGTH Measure the free length of the valve spring. STANDARD: 20.66 mm (0.813 in) SERVICE LIMIT: 20.00 mm (0.7874 in) If the measured length is less than the service limit, replace the valve spring. 13-11 dummyhead CYLINDER HEAD VALVE STEM O.D. Inspect each valve for bending or abnormal stem wear. Measure and record each valve stem O.D. STANDARD: IN: 3.470 3.485 mm (0.1366 0.1372 in) EX: 3.435 3.450 mm (0.1352 0.1358 in) SERVICE LIMIT: IN: 3.400 mm (0.1339 in) EX: 3.380 mm (0.1331 in) If the measurement is less than the service limit, replace the valve (page 13-5). VALVE GUIDE I.D. Measure and record each valve guide I.D. STANDARD: 3.500 3.518 mm (0.1378 0.1385 in) SERVICE LIMIT: 3.560 mm (0.1402 in) If the measured valve guide I.D. is more than the service limit, replace the crankcase set. VALVE STEM-TO-GUIDE CLEARANCE Subtract each valve stem O.D. from the corresponding valve guide I.D. to obtain the stem-to-guide clearance. STANDARD: IN: 0.015 0.048 mm (0.0006 0.0019 in) EX: 0.050 0.083 mm (0.0020 0.0033 in) SERVICE LIMIT: IN: 0.098 mm (0.0039 in) EX: 0.120 mm (0.0047 in) If the calculated clearance is more than the service limit, replace the valves and recheck the clearance. If the clearance is still more than the service limit with the new valve, replace crankcase set. CYLINDER BARREL (Cam pulley shaft bearing I.D.) Measure the cam pulley shaft bearing I.D. STANDARD: 4.000 4.018 mm (0.1575 0.1582 in) SERVICE LIMIT: 4.050 mm (0.1594 in) If the measurement is more than the service limit, replace the crankcase set. 13-12 dummyhead ROCKER ARM AND INSTALLATION RIB CLEARANCE Remove the adjusting screw lock nuts [1] and remove the adjusting screws [2] from the rocker arms. CYLINDER HEAD [1] [2] Open the rocker arm to the outside and check that there is no clearance between the rocker arm [1] and [1] installation guide rib [2], and the projection of the valve lifter [3] and installation guide rib [4]. If there is a clearance between the rocker arm and installation guide rib, replace the rocker arm and valve lifter (page 13-5) and check the cam pulley. [2] [3] [4] 13-13 dummyhead CYLINDER HEAD CYLINDER HEAD INNER COVER Check the oil return passage of the cylinder head inner cover for restrictions. If they are restricted, clean with the compressed air. OIL RETURN PASSAGES INSIDE OUTSIDE 13-14 dummytext 14. MUFFLER MUFFLER REMOVAL/INSTALLATION···· 14-2 EXHAUST PIPE STUD BOLT REPLACEMENT ·································· 14-3 14 14-1 dummyhead MUFFLER MUFFLER MRUFFLER EMOVAL/INSTALLATION The muffler becomes very hot during operation and remains hot for a while after stopping the engine. Touching a hot muffler will severely burn you. Allow the muffler to cool before proceeding. Remove the top cover (page 5-2). AIR EXHAUST GUIDE SPARK ARRESTER SCREW (4 x 6 mm) (2) HEX BOLT (5 x 10 mm) MUFFLER INSTALLATION: After removing any carbon [1] deposits from the muffler, install using a plastic hammer. Do not tap on the muffler seal flange [1] to avoid damaging this part. NUT (5 mm) (2) 14-2 dummyhead EXHAUST PIPE STUD BOLT REPLACEMENT Remove the muffler (page 14-2). Remove the stud bolts [1] from cylinder barrel. Install the stud bolts and tighten to the specified torque. TORQUE: 4.4 N·m (0.45 kgf·m, 3.2 lbf·ft) Check the specified length. SPECIFIED LENGTH: 42 mm (1.7 in) MUFFLER 42 mm (1.7 in) [1] 14-3 dummyhead MEMO IdNumDmEyXtext AAIR CLEANER CHECK/CLEANING ··························3-5 AIR CLEANER REMOVAL/INSTALLATION ················6-3 B BEFORE TROUBLESHOOTING ······························4-2 C CARBURETOR DISASSEMBLY/ASSEMBLY··············6-5 CARBURETOR REMOVAL/INSTALLATION ···············6-4 CASING/VOLUTE CASE REMOVAL/INSTALLATION ······························ 10-4 COMBUSTION CHAMBER CLEANING ·····················3-9 CONTROL BASE/ENGINE STOP SWITCH REMOVAL/INSTALLATION ································7-2 CRANKSHAFT/PISTON INSPECTION ·················· 12-10 CRANKSHAFT/PISTON REMOVAL/INSTALLATION ······························ 12-6 CYLINDER COMPRESSION CHECK···················· 13-10 CYLINDER HEAD COVER/CAM PULLEY REMOVAL/INSTALLATION······························· 13-3 CYLINDER HEAD/VALVES INSPECTION·············· 13-10 D DIMENSIONAL DRAWINGS····································1-5 E ENGINE OIL LEVEL CHECK/CHANGE ·····················3-4 ENGINE P.T.O.SHAFT INSPECTION························8-9 ENGINE REMOVAL/INSTALLATION ······················ 11-2 ENGINE STOP SWITCH INSPECTION ·····················7-3 ENGINE TROUBLESHOOTING ·······························4-2 EXHAUST PIPE STUD BOLT REPLACEMENT········· 14-3 F FAN COVER/ENGINE P.T.O.SHAFT/FLYWHEEL REMOVAL/INSTALLATION ·····································8-5 FUEL TANK REMOVAL/INSTALLATION ···················6-2 FUEL TANK/FUEL FILTER CLEANING ·····················3-9 H HARNESS AND TUBE ROUTING ····························2-6 I IDLE SPEED CHECK/ADJUSTMENT························3-7 IGNITION COIL AIR GAP CHECK/ADJUSTMENT ·······8-7 IGNITION COIL INSPESTION ·································8-8 IGNITION COIL REMOVAL/INSTALLATION···············8-4 IGNITION SYSTEM TROUBLESHOOTING ················8-3 IMPELLER CHECK ············································· 3-10 IMPELLER CLEARANCE CHECK ·························· 3-11 IMPELLER/CASING COVER REMOVAL/INSTALLATION ······························· 10-5 INLET PIPE/OUTLET PIPE REMOVAL/INSTALLATION······························· 10-3 INDEX L LOWER CRANKCASE/SHROUD REMOVAL/INSTALLATION ······························ 12-3 LUBRICATION & SEAL POINT ································2-4 M MAINTENANCE SCHEDULE···································3-3 MAINTENANCE STANDARDS ································2-2 MECHANICAL SEAL REPLACEMENT ···················· 10-6 METERRING LEVER ADJUSTMENT ························6-6 MUFFLER REMOVAL/INSTALLATION···················· 14-2 P PERFORMANCE CURVE ·······································1-4 PUMP INLET VALVE CHECK································ 3-12 R RADIAL BALL BEARING (6001) REPLACEMENT ·······8-9 RECOIL STARTER DISASSEMBLY/ASSEMBLY·········9-2 RECOIL STARTER REMOVAL/INSTALLATION ··········9-3 ROCKER ARM/VALVES REMOVAL/INSTALLATION······························· 13-5 S SERIAL NUMBER LOCATION ·································1-2 SPARK ARRESTER CLEANING ······························3-7 SPARK PLUG CHECK/ADJUSTMENT ······················3-5 SPARK PLUG REPLACEMENT ·······························3-6 SPARK TEST ·······················································8-8 SPECIFICATIONS·················································1-2 STARTER PULLEY REMOVAL/INSTALLATION··········9-3 SYSTEM DIAGRAM IGNITION SYSTEM ···········································8-3 THROTTLE LEVER ADJUSTMENT ··························7-4 TOOL 15 MAINTENANCE ················································3-2 CRANKCASE ················································· 12-2 CYLINDER HEAD ··········································· 13-2 IGNITION SYSTEM ···········································8-2 PUMP ··························································· 10-2 SERVICE INFORMATION···································2-5 TOP COVER REMOVAL/INSTALLATION ··················5-2 TORQUE VALUES ················································2-3 V VACUUM TEST ·················································· 3-13 VALVE CLEARANCE CHECK/ADJUSTMENT ············3-8 W WATER PUMP TROUBLESHOOTING ······················4-5 15-1FrameMaker 11.0.2 Acrobat Distiller 11.0 (Windows)