Cub Cadet The Tank M48 Service Manual 04

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Service Manual

IMPORTANT: READ SAFETY RULES AND INSTRUCTIONS CAREFULLY

PRINTED IN USA FORM NO.769-00966

This Service Manual is not a substitute for the Operator’s Manual. You must read, understand

and follow all of the directions in this manual as well as the Operator’s Manual before working

on this power equipment.

(11/2003)

CUB CADET LLC, P.O. BOX 361131, CLEVELAND, OH 44136-0019

Cub Cadet M48 Tank

TABLE OF CONTENTS

M48 Tank .......................................................................................................... 1

About this Section ............................................................................................. 1

Changes for ‘03 and ‘04 .................................................................................... 1

Drive System Adjustment .................................................................................. 1

Hydro Pump Testing.......................................................................................... 4

Hydro Pump Replacement ................................................................................ 6

Hydro Pump Motor Replacement ...................................................................... 10

Brake Linkage Adjustment ................................................................................ 13

M72 Tank .......................................................................................................... 16

Other Tank Features ......................................................................................... 19

Kohler EFI ......................................................................................................... 23

EFI Controls ...................................................................................................... 26

M48 Tank

1

1. ABOUT THIS SECTION:

The M48 is part of the Cub Cadet Commercial Tank

Series. The 2004 model year M48 is very similar to

The 2001 model year Tank. Earlier versions of this

machine have been covered in the “2001 Cub Cadet

Commercial Technical Handbook”: Form #770-

10528.

2. CHANGES FOR ‘03 AND ‘04

• New hydro motor frame assembly

• New hydro motors

• New brakes and brake linkages

• Finer increments of height adjustment

• Different choice of engines

• Features of the 72” TANK

The content of this section is intended to detail

changes in service techniques that have occurred

since the introduction of the M Series.

3. DRIVE SYSTEM ADJUSTMENT

3.1. Prior to making any adjustments to the drive sys-

tem, inspect the hydro control linkages, drive

belt, brake linkage, tires, fluid, and filter.

3.2. The hydraulic reservoir and filter are accessible

beneath the seat. See Figure 3.2.

Figure 3.2

RESERVOIR

OIL FILTER

BATTERY

3.3. The hydraulic fluid level should be at the second

hole in the filler neck of the reservoir.

See Figure 3.3.

NOTE: It is very important that the hydraulic oil

does not become contaminated. Clean the sur-

rounding area thoroughly prior to opening any

part of the hydraulic system.

NOTE: The hydraulic drive system contains

roughly 3.25 gal. of SAE 20W50 motor oil having

an API rating of SJ-CD or better. Hydraulic

Drive System Fluid Plus (P/N: 737-3121 gal.)

is an acceptable premium alternative.

NOTE: Complete draining and filling instructions

are contained in the “Operator’s and Service

Manual”.

3.4. Tracking is effected by the circumference of the

rear tires, and the amount of drag produced by

the front tires.

•Rear tire pressure may be adjusted within the

range of 8-10 PSI to achieve equal rear tire cir-

cumference.

•Front tire pressure should be within the range

of 20-25 PSI.

Figure 3.3

FLUID LEVEL

FIRST HOLE

SECOND HOLE

M48 Tank

M48 Tank

2

3.5. For complete brake adjustment procedures,

refer to the “Brake Adjustment” section of this

manual. For the purpose of tracking, insure that

the brake linkage bellcranks and rods are well

lubricated, not damaged, and work as intended.

See Figure 3.5.

3.6. To check for brake drag, open the the relief valve

on each hydro pump. With the parking brake

released, both wheels should rotate with hand

pressure. See Figure 3.6.

NOTE: Some hydraulic system drag will be

present, but a dragging brake will be immedi-

ately apparent.

3.7. If in doubt about the source of brake drag, dis-

connect the brake link rod from the actuator arm

on the brake assembly. The actuator arm

should return to center, releasing the brakes.

See Figure 3.7.

3.8. Check the condition of the belt tensioner and

belt that drives the hydro pumps. See Figure 3.8.

3.9. Before making neutral control and tracking

adjustments, make sure the relief valves on both

hydro pumps are fully closed.

3.10. To check neutral control, safely lift and support

the rear wheels of the Tank.

3.11. Start the engine, and release the parking brake.

Do not move the lap bars from the neutral posi-

tion. If either wheel rotates, neutral control

adjustment will be necessary. Turn off the

engine.

Figure 3.5

BRAKE CONNECTING

Link

Brake

REAR BRAKE

ARM ASSEMBLY

BELLCRANK

MOUNTING

ROD

SHAFT

Figure 3.6

HYDRO PUMP

HYDRO RELIEF VALVE

OPEN

Figure 3.7

BRAKE LINK

BRAKE ACTUATOR

ARM

Figure 3.8

DRIVE BELT

TENSIONER

M48 Tank

3

3.12. If adjustment is necessary, remove the cutting

deck.

3.13. Inspect the return to neutral cylinders, rods, and

bellcranks of the hydro control linkages.

• The bellcranks should pivot easily without too

much play.

• The rods should not be bent, and the rod ends

should not be loose.

NOTE: The rod end and jam nut at the rear of

each connector rod have left hand threads. A

lock washer is placed between the control input

arm on the hydro pump and the rod end.

NOTE: The rod end and jam nut at the front of

each connector rod have right hand threads. A

spacer fits between each control hub assembly

(bellcrank) and the front rod end that connects to

it.

• The return to neutral cylinders should both work

as advertised. See Figure 3.13.

NOTE: Remove the control console to gain

access to the return to neutral cylinder.

Figure 3.13

RETURN TO NEUTRAL

CYLINDER (RIGHT)

3.14. Loosen the jam nuts at each end of the hydro

control link rods, and rotate the rods to lengthen

or shorten them. See Figure 3.14.

3.15. Start the engine and release parking brake to

test, then turn the engine off to make the adjust-

ment.

3.16. Tighten the jam nuts against the rod ends when

adjustment is complete, and make a final test to

confirm.

3.17. After neutral control is correctly adjusted, set the

travel stops to achieve correct tracking and

adjust the lap bars for operator comfort.

See Figure 3.17.

NOTE: The clamp bolts for the lap bar mounting

handle can be used to adjust the amount of force

required to move the lap bars into or out of the

neutral slot.

Figure 3.14

Figure 3.17

STOP BOLT

LAP BAR TRAVEL

JAM

NUT

LAP BAR

MOUNTING

HANDLE

CLAMP

BOLTS

M48 Tank

4

3.18. If one side does not drive as effectively as the

other, test the output of the hydro pump to deter-

mine if the problem lies in the pump or the hydro

motor. By the process of elimination, if perfor-

mance is lacking, brake drag is eliminated,

adjustment is correct, and the pump is O.K.,

then the problem is the motor. Pressure and

flow tests will be used to determine if the pump

is the the source of the problem.

4. TESTING HYDRO PUMP OUTPUT

NOTE: The log splitter hydraulic test kit is used

for this set of flow and pressure tests.

4.1. Safely lift and support the rear of the M48.

4.2. If the cutting deck is currently on the unit,

remove it.

4.3. Remove the rear wheels using a 3/4” socket.

See Figure 4.3.

NOTE: The fittings on the lines that connect the

hydro pumps to the hydro motors are 1/2” JIC.

NOTE: 7/8” and 13/16” wrenches will be needed

for this test. A 1” wrench may be needed to hold

the connector that joins the JIC line connection

to the O ring connection on the hydro motor.

4.4. Thoroughly clean the area surrounding any

hydraulic fittings to be loosened or removed.

4.5. If the unit has been run recently, allow it to cool

before doing loosening any hydraulic fittings.

WARNING: Hot hydraulic fluid can cause seri-

ous burns.

WARNING: Release of pressurized hydraulic

fluid can cause serious of fatal injury.

4.6. Open the relief valve on the hydro pump that is

to be tested. This will relieve any residual

hydraulic pressure.

4.7. Confirm that the hydraulic pressure has been

relieved by rotating the brake drum / hub assem-

bly. If the it will not rotate, confirm that the brake

is released and that the brake linkage is not

bound.

4.8. Install a 1/2” JIC double male coupler in one end

of the 18” hydraulic line in the test kit. Install a

90 deg. 1/2” JIC double male elbow in the other

end. See Figure 4.8.

4.9. Position a catch pan beneath the hydro motor.

Have the hydraulic pressure and flow test kit and

two 1/2” JIC plugs within reach.

NOTE: The fittings on the ends of the test kit are

all 1/2” JIC.

4.10. Disconnect the upper line from the hydro motor

and quickly install a 1/2” JIC plug in the line. It

only needs to be finger tight.

Figure 4.3

BRAKE DRUM

HYDRO MOTOR

HIGH PRESSURE LINES:

TOP: in-forward / out-reverse

BOTTOM: out-forward / in-reverse

18” HYDRAULIC

1/2” JIC COUPLER

ELBOW

1/2” JIC

GUAGE

PRESSURE

VALVE

METER

FLOW

Figure 4.8

LINE

M48 Tank

5

NOTE: The test can be performed at either line

between the pump and the motor. The top line

on the motor is the in line from the pump when

driving forward. The linkage has more travel in

forward than it does in reverse, so the test is

most easily done on the top line of the pump,

driving the pump in the forward direction for-

ward.

4.11. Connect the flow meter end of the test kit to the

hydro motor.

4.12. Remove the plug from the line coming from the

outboard port on the hydro pump. Use the 18”

test kit line to connect the pressure gauge end of

the hydraulic test kit to the line coming from the

hydro pump. See Figure 4.12.

4.13. Tighten all the fittings.

4.14. Insure that no unsafe conditions will result from

starting the engine and operating the drive sys-

tem.

CAUTION: The technician will be exposed to

moving parts during this procedure. They

should not reach past or around any moving

parts during this test, nor should they place

themselves in any position where a loss of foot-

ing or balance might bring them into contact with

rotating components. Loose hair or garments

should be secured to avoid the possibility of

entanglement with rotating components.

Figure 4.12

4.15. Remove the stop bolt that sets the end of the

travel of the lap bar that controls the hydro pump

to be tested. See Figure 4.15.

4.16. Confirm that the valve on the test kit is fully

open.

4.17. Start the engine and purge the hydraulic sys-

tem as follows:

4.18. Cycle the lap bar from full forward to full reverse

5 times at 10 second intervals.

4.19. Close the relief valve on the hydro pump and

repeat the cycling process to purge any remain-

ing air from the system.

4.20. Check for and repair any leaks.

4.21. Check the fluid level in the hydraulic reservoir.

Top it up if necessary.

4.22. Continue to operate the drive system to warm-up

the hydraulic fluid.

NOTE: Performing the test with cold fluid will

make a significant difference in the flow readings

obtained. The test will not be valid.

Figure 4.15

STOP BOLT

JAM NUT

M48 Tank

6

4.23. When the fluid is between 160-210 deg. f.

(71-90 deg. c.) apply full forward drive pressure

to the lap bar with the engine running at full

speed (3600 RPM) while an assistant closes the

valve to the point where pressure reaches 300

PSI (21 Bar.). See Figure 4.23.

NOTE: It may be necessary to over-shoot 300

PSI slightly, then open the valve to reduce pres-

sure to 300 PSI.

4.24. Take note of the reading on the flow meter por-

tion of the test kit when the pressure gauge

reads 300 PSI.

4.25. Continue closing the valve until the pressure

reading reaches 1,100 PS I (76 bar.). Take note

of the flow reading. See Figure 4.25.

4.26. Subtract the 1,100 PSI flow reading from the 300

PSI flow reading. The resulting figure is called

“flow droop”.

4.27. Interpretation: flow droop greater than 1.5 GPM

indicates a pump that is not performing as well

as it should.

NOTE: A blocked filter may account for some

loss of performance.

4.28. Within the two year Cub Cadet Commercial war-

ranty period, replace the pump if it does not per-

form as specified and all other factors have been

eliminated.

4.29. If a hydro pump requires repair, refer to Hydro-

Gear publication “BLN-51337” for complete ser-

vice instructions.

4.30. If the hydro pump and all other factors are O.K.,

replace the hydro motor.

NOTE: The hydro motor is not serviceable.

Replace it as a unit if it fails.

5. REPLACING THE HYDRO PUMP

5.1. If the cutting deck is currently on the unit,

remove it.

5.2. Safely lift and support the rear of the tank.

5.3. Remove the rear wheels using a 3/4” socket.

5.4. Tilt the seat up, and disconnect the negative bat-

tery cable.

5.5. Remove the screen that covers the opening over

the cooling fans on the hydro pump to be

removed using a 3/8” wrench. See Figure 5.5.

Figure 4.23

FLOW

300 PSI

10 GPM

BUILD PRESSURE

CLOSE VALVE TO

SPINNING

CONTROL

CONSOLE INSET:

3600 RPM

Figure 4.25

1100 PSI

9 GPM

VALVE CLOSED

FURTHER

Figure 5.5

REMOVE DEBRIS SCREEN

M48 Tank

7

5.6. Remove the nut, washer, and cooling fan from

the hydro pump to be replaced, using a 9/16”

wrench. See Figure 5.6.

5.7. Use a 3/8” breaker bar to move the belt ten-

sioner pulley arm, slipping the belt off of the pul-

ley. See Figure 5.7.

5.8. Unhook the spring that maintains tension on the

arm. This will provide more freedom of move-

ment.

5.9. Slip the belt over the drive pulley of the hydro

pump to be removed.

FAN NUT

WASHER

Figure 5.6

Figure 5.7

TENSIONER

PULLEY ARM

SPRING

5.10. Use a small two-jaw puller to remove the pulley

from the tapered and keyed input shaft of the

hydro pump. See Figure 5.10.

5.11. Disconnect the rod end on the back of the hydro

control rod from the control arm on the hydro

pump using a 9/16” wrench, and a 1/2” wrench.

See Figure 5.11.

NOTE: There is a lock washer positioned

between the rod end and the control arm.

5.12. Thoroughly clean the area surrounding any

hydraulic fittings to be loosened or removed.

5.13. If the unit has been run recently, allow it to cool

before doing loosening any hydraulic fittings.

WARNING: Hot hydraulic fluid can cause seri-

ous burns.

WARNING: Release of pressurized hydraulic

fluid can cause serious of fatal injury.

Figure 5.10

PULLER

PULLEY

Figure 5.11

ROD END

BOLT

LOCK WASHER

NUT

CONTROL ARM

M48 Tank

8

5.14. Open the relief valve on the hydro pump that is

to be tested. This will relieve any residual

hydraulic pressure. See Figure 5.14.

5.15. Confirm that the hydraulic pressure has been

relieved by rotating the brake drum / hub assem-

bly. If the it will not rotate, confirm that the brake

is released and that the brake linkage is not

bound.

5.16. If there is any possibility of fluid contamination,

drain and flush the system, and replace the filter

before installing the new hydro pump.

5.17. Position a catch pan beneath the hydro pump to

be removed. Have four 1/2” JIC plugs and two

1/2” JIC caps within reach.

5.18. Disconnect the feed line that runs from from the

front of the hydro pump to the filter manifold

using a 7/8” wrench on the nut, and a 13/16”

wrench to hold the fitting on the hydro pump.

Plug the line, cap the fitting on the pump.

5.19. Disconnect the return line that runs from from

the outboard side of the hydro pump to the res-

ervoir using a 7/8” wrench on the nut, and an 11/

16”” wrench to hold the fitting on the hydro

pump. Plug the line, cap the fitting on the pump.

See Figure 5.14.

5.20. Disconnect the two lines that connect the hydro

motor to the back of the hydro pump using a pair

of 7/8” wrenches. Plug the lines.

See Figure 5.20.

5.21. Remove the two O ring to JIC adaptors from the

back of the hydro pump. Replace them with the

yellow shipping plugs from the replacement

hydro pump.

5.22. Remove the 90 deg. elbow fitting that the return

line was connected to using an 11/16” wrench

and a 3/4” wrench. Plug the port using a yellow

shipping plug removed from the replacement

pump.

5.23. Remove the O ring to JIC adaptor that the feed

line was connected using a 13/16” wrench. Plug

the port using a yellow shipping plug removed

from the replacement pump. See Figure

5.23.

Figure 5.14

RETURN LINE

FEED LINE

OPEN

CLOSE

RELIEF VALVE

ELBOW

Figure 5.20

HYDRO

MOTOR

HYDRO

PUMP PRESSURE LINES

BETWEEN PUMP

AND MOTOR

ADAPTORS

Figure 5.23

M48 Tank

9

5.24. Remove the handle from the relief valve using a

7/16” wrench and a 3/16” allen wrench.

5.25. Remove the nuts from the carriage bolts that

hold the hydro pump to the hydro pump mount-

ing plate. See Figure 5.25.

5.26. Carefully lower and remove the hydro pump. If it

is to be returned to Cub Cadet, remove the yel-

low plugs and allow it to drain completely before

packing and shipping it.

5.27. Inspect all of the fittings and O rings prior to

installation in the replacement pump.

See Figure 5.27.

5.28. Prior to installation, pour oil directly into the

pump inlet and high-pressure ports, then trans-

fer yellow plugs back to the replacement pump.

Figure 5.25

RELIEF VALVE

HANDLE REMOVE

D

FITTINGS REMOVED

AND PLUGGED

MOUNTING NUT

Figure 5.27

GOOD O RING

DEFORMED O RING

CHECK

THREADS

CHECK TAPERED SEATS

5.29. Position the pulley over the opening in the hydro

pump support plate that the pump input shaft will

pass through.

5.30. Position the pump so that the two bolts that

secure it in position line-up with the two mount-

ing ears on the pump, and the input shaft slips

into the pulley as the pump is raised up to the

hydro pump support plate. See Figure 5.30.

5.31. Start both nuts that hold the pump onto their car-

riage bolts.

5.32. As the pump is tightened into position, rotate the

pulley to align the keyways, allowing the pulley

to seat on the input shaft.

5.33. Install the fittings and lines, working quickly to

minimize fluid loss.

NOTE: Use care not to over-tighten the O ring

fittings, damaging the O rings.

NOTE: The lines may be installed finger tight to

establish their positions, then tightened fully.

5.34. Install the belt, tension arm spring, steering link-

age.

5.35. Install the fan, washer and nut to the input shaft.

Torque the nut to 240 inch/lbs.

5.36. Install the debris screen.

5.37. Check the fluid level in the reservoir, purge the

system as described in the test instructions.

5.38. If the hydraulic system has been drained and

flushed with 20W50, install a new filter and fol-

low the instructions for refilling the hydraulic sys-

tem in the “Operator’s and Service Manual”.

Figure 5.30

NEW PUMP

MOUNTING BOLT

PULLEY WITH KEY

M48 Tank

10

5.39. Install the wheels, lower the TANK to the ground,

and test run it in a safe area. Make any neces-

sary adjustments before installing the cutting

deck.

6. REPLACING THE HYDRO MOTOR

6.1. If the cutting deck is currently on the unit,

remove it.

6.2. Safely lift and support the rear of the tank.

6.3. Remove the rear wheels using a 3/4” socket.

6.4. Tilt the seat up, and disconnect the negative bat-

tery cable.

6.5. Thoroughly clean the area surrounding any

hydraulic fittings to be loosened or removed.

6.6. If the unit has been run recently, allow it to cool

before doing loosening any hydraulic fittings.

WARNING: Hot hydraulic fluid can cause seri-

ous burns.

WARNING: Release of pressurized hydraulic

fluid can cause serious or fatal injury.

6.7. Open the relief valve on the hydro pump. This

will relieve any residual hydraulic pressure.

See Figure 6.7.

6.8. Confirm that the hydraulic pressure has been

relieved by rotating the brake drum / hub assem-

bly. If the it will not rotate, confirm that the brake

is released and that the brake linkage is not

bound.

Figure 6.7

OPEN

M48 Tank

11

6.9. If the brake assembly is to be transferred to the

new hydro motor: remove the cotter pin from the

castle nut that holds the hub to the axle.

6.10. Loosen, but do not remove the castle nut from

the axle using a 11/2” socket.

NOTE: It may be necessary to set the parking

brake while loosening the nut. Release the

parking brake afterward.

NOTE: The studs are pressed into the brake

drum. The brake drum effectively is the drive

hub. The drive hub mounts on an narrow taper.

6.11. Remove the hairpin clip that secures the brake

link to the brake arm. Pivot the arm out of the

way. See Figure 6.13.

6.12. Place a catch pan under the hydro motor, and

have two 1/2” JIC plugs within reach.

Figure 6.11

BRAKE

LINK

BRAKE

ARM

HAIRPIN CLIP

COTTER

PIN

CASTLE

NUT

HIGH

PRESSURE

LINES

6.13. Disconnect the high pressure lines from the the

hydro motor one at a time using a 7/8” wrench.

A 1” wrench may be required to hold the fittings

on the hydro motor. Plug the lines.

See Figure 6.13.

6.14. Remove the four sets of nuts and bolts that hold

the hydro motor to the hydro motor frame

assembly using 3/4” wrenches.

6.15. Lift the motor slightly and carefully pull it out far

enough to remove the motor plate from the end

of the four bolts. See Figure 6.15.

NOTE: The hydro motor weighs nearly 50 lbs.

Figure 6.13

DISCONNECT MOUNTING

BOLTS

Figure 6.15

MOTOR SPACERS

MOTOR

PLATE

M48 Tank

12

6.16. Withdraw the hydro motor, along with the three

motor spacers, and place them gently on a work

bench. See Figure 6.16.

6.17. If the brake is to be removed, remove the clip

that holds the brake arm on the splined shaft,

and mark the location of the brake arm on the

splined shaft.

6.18. Remove the brake arm from the splined shaft.

NOTE: The Hydro motor can be ordered with or

without the brake assembly. If an appropriate

size press is not available, the dealer should

consider ordering hydro motor with the brake

assembly attached.

6.19. Safely fixture the hydro motor and brake assem-

bly in a minimum 20 Ton press so that the ram

presses against the end of the axle, and the

assembly is supported by the edge of the brake

drum. Press the drum off of the tapered shaft.

6.20. Remove the castle nut and brake drum from the

axle. See Figure 6.20.

6.21. Mark the orientation of the brake assembly on

the hydro motor.

6.22. Remove the four socket head cap screws that

hold the brake assembly to the hydro motor

using a 1/4” allen wrench.

6.23. Transfer the four mounting bolts from the old

hydro motor to the new one. Replace any that

show signs of wear or damage.

6.24. Position the three motor spacers on the bolts,

and install the hydro motor in the TANK.

6.25. Place the motor plate over the end of the bolts,

apply Loctite 242 (blue) the the bolts, and install

the four nuts. Tighten the bolts to 450-550 in.-

lbs.

6.26. Inspect the brake assembly. If there are not

signs of significant wear or damage, install the

brake on the new hydro motor, using the match

marks to maintain the same orientation.

6.27. Use new lock washers and / or Loctite 242 (blue)

when installing the brake assembly. Torque the

socket head cap screws to 160-200 in.-lbs.

Figure 6.16

Figure 6.17

Figure 6.20

BRAKE

ASSEMBLY

ORIENTATION MARKS

(ARROW TO FITTINGS)

DRUM

BRAKE

M48 Tank

13

6.28. Install the brake arm and clip on the new hydro

motor. See Figure 6.28.

6.29. Transfer the O ring to flare adaptor fittings from

the old hydro motor to the new hydro motor,

using a 1” wrench. Inspect the fittings and O

rings. If there is any doubt about their condition,

replace them. Lightly lubricate the O rings with

oil on assembly.

6.30. Apply a small amount of anti-seize compound to

the taper of the brake drum, and install the brake

drum on the axle.

6.31. Install the castle nut on the axle, and lock it with

a fresh cotter pin.

6.32. Connect the brake linkage.

6.33. Install the rear wheels, and torque the lug nuts to

50-70 ft.-lbs.

6.34. Check the fluid level in the reservoir, purge the

system as described in the pressure and flow

test instructions.

NOTE: If the hydraulic system has been drained

and flushed with 20W50, install a new filter and

follow the instructions for refilling the hydraulic

system in the “Operator’s and Service Manual”.

6.35. Install the wheels, lower the TANK to the ground,

and test run it in a safe area. Make any neck-

laces adjustments before installing the cutting

deck.

Figure 6.28

7. BRAKE LINKAGE ADJUSTMENT

7.1. With the TANK parked on firm level ground, lift

and safely support the back of the unit.

7.2. Remove the hairpin clips that hold the floor panel

in position.

7.3. Lift the floor panel up using the grip opening at

the top rear edge, slide it to the left, and remove

it. See Figure 7.3.

7.4. Release the hydro relief valves and release the

parking brake.

7.5. Rotate each wheel to confirm that the brakes are

not dragging or binding.

7.6. Remove the rear wheels using a 3/4” socket.

NOTE: It may be necklaces to set the parking

brake while loosening the lug nuts.

Figure 7.3

M48 Tank

14

7.7. Loosen the jam nut that locks the shoulder nut in

position on the brake connector rod using a

9/16” wrench and a 3/4” wrench. See Figure 7.7.

7.8. Remove the hairpin clip that secures the brake

link rod to the brake arm on the brake assembly.

7.9. Repeat on other side.

7.10. Disconnect the brake link rods (left and right).

See Figure 7.10.

7.11. Remove the hairpin clip and clevis pin that

secures the clevis on the end of the brake con-

nector rod to the rear brake arm assembly on

both sides. See Figure 7.11.

7.12. Confirm that the rear brake arm assembly

moves freely on the rear bellcrank shaft, is suffi-

ciently well lubricated, and is free from excessive

play caused by worn busings. See Figure 7.12.

NOTE: If rear brake arm assembly service is

needed, the rear bell crank shaft that the arms

pivot on can be easily removed by unbolting the

brake shaft holders, removing the cotter pins

and washers that locate the brake arm assem-

blies on the shaft.

NOTE: Both washers that fit next to each rear

brake arm go between the arm and the cotter

pin.

Figure 7.7

SHOULDER NUTS

BRAKE CONNECTOR RODS

JAM NUTS

Figure 7.10

BRAKE LINK ROD REAR BRAKE

ARM ASSEMBLY

Figure 7.11

REAR BRAKE

ARM ASSEMBLY

BRAKE

CONNECTOR ROD

BRAKE

LINK

ROD

REAR

BELLCRANK

SHAFT

BUSHING

Figure 7.12

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7.13. Confirm that the brake bearing hub, brake han-

dle, and the brake rod that connects them move

freely on the front bellcrank shaft.

7.14. Confirm the position of the brake bearing hub:

the top of the arm that the brake rod (to the

brake handle) connects to should line-up directly

with the parking brake switch, and the brake rod

should be parallel to the frame. When this is

true, the front brake connector rods should also

be parallel to the frame. See Figure 7.14.

7.15. If adjustment is necklaces, loosen the two collars

on the front bellcrank shaft using a 1/8” allen

wrench. Re-position the bearing hub and collars

as necklaces, and tighten the collars.

See Figure 7.15.

NOTE: The left edge of the brake bearing hub

will usually be even with the inner edge of the

frame when correctly adjusted.

Figure 7.14

BRAKE

HANDLE

BRAKE ROD

BRAKE BEARING HUB

ARM

BRAKE

SWITCH

Figure 7.15

COLLAR

BRAKE

BEARING

HUB

FRONT

SHAFT

BELLCRANK

7.16. Check the brake arm on the brake assembly for

freedom of movement. It should return to center.

7.17. Reconnect the brake link rods and brake con-

necting rods to the rear brake arm assemblies.

7.18. Apply light rearward pressure to each brake con-

necting rod. The clevis pin at the rear end of the

rod should just contact the back of the hole that

it passes through to connect the clevis to the

rear brake arm assembly.

7.19. Loosen or tighten the nylock nut at the front of

the connecting rod to bring the heavy spring

lightly into contact with the brake bracket.

See Figure 7.19.

7.20. Apply the parking brake. The gap between the

bottom edges of the brake bracket and the cross

member that it rests against in the released posi-

tion should be roughly 1 3/4”. See Figure 7.20.

Figure 7.19

LIGHT

CONTACT

RETURN LINKAGE

FORCE TO

SUFFICIENT

ADJUST

HEAVY

SPRING

HERE

ADJUST RETURN

SPRING HERE

Figure 7.20

1 3/4”

ADJUST

HERE

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7.21. Release the parking brake.

7.22. The brake bracket should draw up against the

frame cross member. If this reaction is not con-

sistent, tighten the shoulder nut slightly. There

should be roughly 1 1/2” between the head of

the shoulder nut and the brake bracket when the

brakes are applied.

7.23. Tighten the jam nut.

7.24. If brake application is uneven from left to right,

adjust the length of the short connector rods

between the brake bracket and the brake bear-

ing hub.

7.25. If brake release action is inconsistent, check for

bent or misaligned rods and links.

7.26. Install the rear wheels, tightening the lug nuts to

50-70 ft.-lbs. Lower the TANK to the ground.

7.27. Install the floor panel.

7.28. Test run the TANK in a safe area before return-

ing it to service. Check the function of the park-

ing brakes.

NOTE: A dragging parking brake will cause

tracking issue and drive noise on the effected

side.

8. M72 TANK

The M72 is based on the same frame design as the

smaller members of the TANK series. Some changes

have been made to accommodate the larger deck.

8.1. Heavier brackets to suspend the deck.

See Figure 8.1.

8.2. Heavier duty deck belt tension release mecha-

nism. See Figure 8.2.

Figure 8.1

Figure 8.2

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8.3. The deck lift goes has finer increments of adjust-

ment. See Figure 8.3.

8.4. The larger, heavier decks have a foot assist

pedal to help raise and lower the deck.

See Figure 8.4.

Figure 8.3

Figure 8.4

8.5. Heavier hardware connects the deck to the

hangers. See Figure 8.5.

8.6. Heavier front pivot bar and wider front track.

See Figure 8.6.

Figure 8.5

Figure 8.6

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8.7. The track at the rear has also increased. Extra

brackets have been added to the frame to step

the hydro motors out. See Figure 8.7.

8.8. To enable the brake linkage to reach the reposi-

tioned hydro motor, the rear brake arm assem-

blies have been doubled-up on each side.

Instead of a single rear brake arm assembly per

side, two are used in tandem. See Figure 8.8.

8.9. The parking brake lever has been moved up to a

more convenient location.

8.10. A larger engine is required to power the larger

deck and heavier total weight of the mower. A

28 H.P. Generac Guardian engine is employed.

See Figure 8.10.

Figure 8.7

Figure 8.8

Figure 8.9

Figure 8.10

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9. OTHER TANK FEATURES

9.1. Honda Power is offered on the M48-HN and

M54-HN. The M48-HN has a 20 H.P. Honda V-

twin engine. The M54-HN has a 24 H.P. Honda

V-twin. See Figure 9.1.

9.2. ROPS is offered on the M60-KW (Kawasaki) and

M60-KH (Kohler). This is not a bolt-on option. It

is integrated into the frame. The option is prima-

rily aimed at government bid specifications. See

Figure 9.2.

Figure 9.1

Figure 9.2

9.3. The TANK exhaust systems all feature a new

aluminized finish. This finish resists corrosion

better than the heat paint that is more commonly

used. It also dissipates heat more effectively,

producing noticeable improvements on chassis

dynamometers. See Figure 9.3.

9.4. Some features of the 72” deck have been

extended throughout the TANK model range.

Looking at the 60” model as an example, these

features include:

9.5. More easily adjustable hydro control link.

See Figure 9.5.

Figure 9.3

Figure 9.5

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9.6. 1/4” increments on the height adjuster, with foot

assist deck lift. See Figure 9.6.

9.7. The deck belt release operates in a vertical

plane. It can be tensioned with foot pressure,

and the rear wheel does not interfere with its

travel. See Figure 9.7.

9.8. Heavy duty spherical rod ends on the arms at

the front of the deck. See Figure 9.8.

9.9. The arms themselves are cast iron, and the lift-

shaft is heavier. See Figure 9.9.

Figure 9.6

Figure 9.7

Figure 9.8

Figure 9.9

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9.10. The deck itself features reversible caster wheel

brackets. The same part number applies to both

the left and the right brackets. See Figure 9.10.

9.11. Improved self-aligning pillow blocks now sus-

pend the deck. See Figure 9.11.

Figure 9.10

Figure 9.11

9.12. The deck support plates are larger this year, to

prevent plate bending and separation.

See Figure 9.12.

9.13. The baffling, airflow, and strength of the deck

have all received some improvements this year.

9.14. The trailing edge of the discharge opening has

been swept back, and the bar that prevents foot

penetration has been modified. Both changes

improve strength and airflow. See Figure 9.14.

Figure 9.12

Figure 9.14

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9.15. A guiding baffle near the rear of the opening

helps direct the clippings out from under the

deck. See Figure 9.15.

9.16. The addition of a “California Gap” at the leading

edge also improves airflow, and products the

internal shape of the deck from damage if some-

thing is hit hard enough to bend the reinforced

leading edge. See Figure 9.16.

9.17. The under-deck baffling has been reinforced,

and a “stealth baffle” has been added between

the second and third blades. See Figure 9.17.

Figure 9.15

Figure 9.16

Figure 9.17

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10. KOHLER EFI

Fuel injection is nothing new. The Wright flyer that

made history above the dunes at Kitty hawk, North

Carolina was fuel injected. That was a hundred years

ago this past summer. That system was only slightly

more complex than a cam-driven Windex bottle. All

diesel engines are fuel injected, though the principles

of operation are considerably different.

Electronic fuel injection is not an especially recent

development either. In 1956, Chrysler marketed the

first car with electronic fuel injection. The fuel injection

system used was made by Bendix, and was called

“The Bendix Electrojector System”. It was operated by

a large Electronic Control Module that took up most of

the trunk. The ECM used relatively delicate tubes,

generated a lot of heat, and was susceptible to mois-

ture, temperature changes, vibration, and shock. Most

of these systems were discarded, and the cars retrofit-

ted with carburetors.

There were mechanical gasoline fuel injection systems

on the market before the Bendix system was intro-

duced. Rochester and Bosch were fairly prominent.

The auto industry made the transition to electronic fuel

injection in the 1970s and 80s, in response to emission

control and fuel economy standards.

Even the best-tuned carburetion system only offers and

approximation of the correct fuel mixture for any given

operating condition. They can be tuned to provide

“sweet spots”, but generally cannot maintain an ideal

mixture for all speeds, loads, temperatures, and condi-

tions.

Carburetors also cost efficiency by “working” the air.

the venturi effect that is used to atomize the fuel

requires a pressure drop within the throat of the carbu-

retor. The venturi that creates this pressure drop is a

partial obstruction of the path into the engine.

Until recently, the advantage offered by fuel injection

have not been worth the expense that they add to out-

door power equipment. Fuel injection systems have

become less expensive and more dependable in the

past two decades. At the same time, commercial turf

equipment in specific, and outdoor power equipment in

general have become more sophisticated and more

expensive. Performance and expectations have

improved. The final factor is the increase in the price of

fuel.

All of these factors combine to make EFI worthwhile for

some applications. The improved fuel economy

reduces fuel expense for heavy (Commercial) users. It

also increases range, requiring fewer stops to replenish

fuel.

10.1. For 2004, one model of TANK will be offered

with a Kohler 28 H.P. EFI engine. That unit is a

60” Wide-Track model. That model is built on

the widened M72 frame, but features a 60” deck.

10.2. The fuel injection system used on the the Kohler

powered TANK uses a high pressure electric fuel

pump. The pump generates 3 bars. of pressure

(roughly 40 PSI.), and is capable of moving 25

liters per hour of fuel. This is more fuel volume

than the engine will consume, but it is necessary

in order to maintain pressure under all fuel

demand conditions.

10.3. Because there is more fuel supplied to the injec-

tors than the engine will consume, return lines

route the excess volume back to the fuel tanks.

See Figure 10.3.

10.4. The fuel lines from each tank Tee into a single

line that feeds the fuel pump. See Figure 10.4.

Figure 10.3

Left fuel tank

(1 of 2)

Fuel pick-up

and valve

Fuel return line

Figure 10.4

From left tank

From right

tank

To pum p From pump

to filter

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10.5. The return lines each lead back to the tank from

a tee fitting just beneath the tee fitting for the fuel

feed lines. The return fuel comes from the fuel

pressure regulator.

NOTE: If one branch of the return line becomes

crushed, kinked, or blocked, a disproportionate

amount of fuel will return the the opposite tank.

• If one fuel tank consistently empties before the

other, check the return lines.

• If this situation should occur with full tanks, an

over-flow will result.

10.6. The fuel feed line leads from the tanks and tee

down to a high pressure fuel pump located

beneath the ECM. See Figure 10.6.

CAUTION: Before disconnecting any fuel line:

• Allow the engine to cool, and be sure the area is

clear of any potential fire hazards, and has ade-

quate ventilation.

• Have a catch pan handy to contain any spillage

• Relieve pressure from the any fuel lines between

the fuel pump and the fuel rail.

NOTE: The fuel pump uses the fuel as a coolant.

If the engine runs out of fuel, turn the key off

immediately. Running dry will damage the

pump.

NOTE: The fuel pump will run briefly each time

the key switch is turned on. This pressurizes the

system. If fuel pressure is absent, and the fuel

pump cannot be heard when the key switch is

turned on, the fuel pump may not be getting

electricity. Check for power before condemning

the fuel pump.

NOTE: The fuel pump is protected by an internal

60µ filter.

10.7. The pump sends pressurized fuel to the fuel

pressure regulator. The regulator maintains a

constant down-stream pressure of between 36

and 42 PSI. See Figure 10.7.

NOTE: High pressure fuel lines (SAE R9 rating)

and Oetiker style hose clamps must be used

between the fuel pump, pressure regulator, fuel

filter, and fuel injector rail.

CAUTION: Substitution of fuel system compo-

nents that are not capable of handling the pres-

sure generated by this fuel system will lead to

rapid failure of those components. Component

failure (hose, clamps, filter, etc...) in the high

pressure portion of the system poses a signifi-

cant fire hazard.

Figure 10.6

Electronic

Control

Module

Fuel pump

Figure 10.7

Fuel pump

regulator

pressure

Fuel

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10.8. There are two lines exiting the pressure regula-

tor. One is a regulated pressure line that feeds

the fuel rail via the fuel filter. The second line is

a return line. The third line is a high pressure

feed from the fuel pump. See Figure 10.8.

NOTE: There are two potential failure modes for

pressure regulators. They may reduce the pres-

sure too far, or they may not reduce the pressure

far enough. The second mode is more common.

NOTE: If too much pressure is delivered to the

injectors, the engine will run extremely rich. The

problem will be very pronounced at idle, but will

clear up to some extent under high load / open

throttle conditions.

NOTE: When an engine has run dramatically

rich, correct the core problem and change the oil

before continued operation. Oil dilution that may

result from the rich condition may cause hydro-

lock and/or catastrophic engine failure.

NOTE: Check fuel pressure by connecting a fuel

pressure gauge of adequate range (eg. NAPA /

Balkamp part number BK.700-1089) to the

shrader valve on the fuel rail. This will check

regulated fuel pressure. If fuel pressure at the

shrader valve is below 36 PSI, isolate the fuel

pump, and check output pressure and volume.

Figure 10.8

High pressure

from fuel pump

Regulated pressure

to rail, via filter

Return

to tanks

Vacuum barb

(not used

for this

application)

10.9. The fuel filter is easily accessible.

See Figure 10.9.

NOTE: Use only identical factory replacement

fuel filters. Filters that are not capable of func-

tioning at 3 bar. may rupture, leak, or disinte-

grate internally.

NOTE: Prime the fuel filter with a few ounces of

fuel when installing it. The initial pressure surge

into a dry filter may damage filtering medium.

NOTE: Fuel filters should be replaced at regular

intervals specified in the Operator’s Manual. A

blocked fuel filter puts extra load on the pump.

creating extra heat. This may lead to shortened

fuel pump life. Fuel pumps are much more

expensive than fuel filters. A blocked filter may

not present symptoms until the blockage is sub-

stantial enough to damage the fuel pump.

10.10.After the filter, the fuel reaches the fuel rail. The

fuel rail feeds the injectors. See Figure 10.10.

Figure 10.9

Fuel filter

To fuel rail

From

pump

M48 Tank

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10.11. The shrader valve can be used for checking fuel

pressure. Fuel pressure readings obtained at

the shrader valve can help pin-down problems

with the fuel pump or the fuel pressure regulator.

See Figure 10.11.

10.12.Before any service is performed on the pressur-

ized portion of the fuel system, the engine must

be allowed to cool, and the pressure should be

relieved.

10.13.To relieve pressure from the fuel system:

• Turn the key switch off.

• Remove the 10A in-line fuse that protects the

fuel pump.

• Start the engine normally. It will run for only a

few seconds.

• Turn the key switch off.

11. EFI CONTROLS

The Fuel injection system used by Kohler is an

adapted version of the Bosch Motronic automotive sys-

tem.

NOTE: Do not connect or disconnect any electri-

cal components with the key switch in the “on”

position. The resulting arc could cause immedi-

ate and sever damage to the ECU.

NOTE: If using a circuit tester, use only a high

impedance tester (eg. Thexton model 125).

Conventional testers pass the current they are

checking through a small incandescent bulb. In

some cases, the bulb draws more power than

the circuit in the computer, over-loading the cir-

cuit and complicating the diagnostic process by

inducing a circuit failure. High impedance

testers do not actually pass much current, and

the LED indicator will not draw enough power to

damage the circuitry. See Figure 11.0.

11.1. The EFI engine has a throttle valve or “air valve”

similar to that of a carburetor. There is no fuel

mixed into the air at this point. The throttle valve

only regulates the amount of air that enters the

engine.

11.2. The throttle responds to the governor just like it

would with a carburetor.

11.3. The computer (ECU) takes in information from

various sensors, and decides how much fuel the

engine should have to maintain a correct fuel/air

mixture. The ECU then sends electrical pulses

to the individual injectors, triggering them to

spray fuel into the intake tract.

Figure 10.10

Fuel injector

Fuel

rail

electrical

connection

for injector

Cap for

shrader

valve

Figure 10.11

Figure 11.0

M48 Tank

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11.4. The fuel pressure at the injectors is held con-

stant by the fuel pressure regulator. The amount

of fuel delivered to the cylinders is controlled by

the length of time that the individual fuel injectors

are triggered. The length of time the injectors

are triggered varies from 1.5 to 8.0 milliseconds.

11.5. Both injectors are triggered simultaneously.

Each triggering causes the injector to spray half

the amount of fuel required by the corresponding

cylinder on the next cycle.

11.6. The injectors are “hot” as long as the key switch

is on. The injection is triggered by the comple-

tion of a ground path within the ECU.

11.7. The injectors make an audible “click” each time

they are triggered. If this click cannot be heard

or felt, there may be a problem with the injector

itself, or there may be a problem in the wiring

harness.

11.8. If a fuel injector is suspect, the circuit may be

tested with a commonly available “noid” light, or

the injector may be triggered using an electronic

fuel injection pulse timer (eg. Thexton model

number 139) in conjunction with a fuel pressure

gauge. With the key switch off, triggering the

injector should result in a measured drop in fuel

pressure.

Figure 11.7

11.9. The ignition coils are also controlled by the ECU.

Each cylinder has its own coil. See Figure 11.9.

11.10. The plastic-cased ECU is mounted to the frame,

above the fuel pump. See Figure 11.10.

11.11. The ECU is the brain of the engine control sys-

tem. It is very durable, but there are some rules

to follow in order to avoid damage to the ECU:

• If you diagnose a faulty ECU, do not replace it

without calling Cub cadet Technical Support for

specific handling instructions.

• Previously mentioned: do not use a conventional

test light to look for power in the engine control

circuit.

• Previously mentioned: do not disconnect any

electrical devices while the engine is running.

• Do not reverse the battery terminal connections.

Figure 11.9

Figure 11.10

M48 Tank

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• Do not connect a battery charger to the TANK

with the key switch turned on.

• The ECU requires at least 7.0 volts to function.

• If the battery goes dead, or is disconnected, the

adaptive memory in the ECU will be cleared. It

will take 10-15 minutes of running, at normal

operating temperatures, under a variety of loads

and throttle settings to re-learn the full envelope

of performance. Clearing the memory will also

clear diagnostic trouble codes.

• The ECU receives signals from a variety of sen-

sors. These include: crankshaft speed and posi-

tion, throttle position, engine temperature,

oxygen content of the exhaust gas, battery volt-

age.

• There is an indicator light that flashes diagnostic

codes in the event that there is a malfunction. If

the signal from any of the sensors are not in the

range that the ECU is expecting from compari-

son to its adaptive memory, a code will flash.

• In the event of a malfunction, the ECU has a

“limp home” mode that will allow it to plug in a

fixed value in place of the reading from the mal-

functioning sensor.

11.12. The Throttle Position Sensor tells the ECU what

the position of the throttle plate is. It is essen-

tially a potentiometer. See Figure 11.12.

• If a TPS fails, it will result in rough or erratic

engine performance. If a “dead” spot develops

in the potentiometer, the engine will run badly

whenever the throttle is in a position that corre-

sponds with the “dead” range of the TPS.

• The TPS can be checked with an Ohm meter,

looking for “jumps” as the throttle is swept

through its full range of travel.

• If the TPS mounting is disturbed for any reason,

there is a Kohler-specified initialization proce-

dure that must be performed.

11.13. The engine temperature has a bearing on the

fuel/air mixture and ignition timing. The ECU

“takes the engine’s temperature” with a ther-

mometer in the engine oil.

• When the engine is cold, the oil temperature is

the same as the ambient temperature. Being an

air-cooled engine, as the engine warms-up, the

oil temperature reflects a balance between

engine load and ambient temperature when

operating normally. This is sufficient for the pur-

poses of the ECU.

• A bad temperature sender may result in rich fuel/

air mixture accompanied by an erratic idle and

somewhat reduced WOT power.

• At 68deg. f, (20deg. c), the Ohm reading across

the terminals of the oil temperature sensor

should be in the 2375-2625 υ range.

11.14. In order to coordinate the timing of the fuel injec-

tor triggering, as well as tune the fuel delivery

and ignition timing to match the load applied to

the engine, the ECU needs to know the speed

that the crankshaft is spinning and the position

of the crankshaft.

• There is a 60 tooth ferrite ring gear on the fly-

wheel. This ring gear is separate from the

starter motor ring gear. A Hall-effect pick-up

mounted .049”-.069” from the ring gear gener-

ates a pulse as each tooth passes by. The ECU

counts the pulses to determine engine RPM.

• There are two consecutive teeth missing from

the ring gear. The ECU gets a signal from each

of the present teeth every 6 degrees of crank-

shaft rotation. The 12 degree gap is positioned

84 degrees before cylinder #1 reaches TDC.

This tells the ECU where the engine is in terms

of piston position.

• Each time the engine is started, it will take 720

degrees of crankshaft rotation for the ECU to

“find” the piston and begin working.

• Comparing engine speed to throttle position, the

ECU can interpolate the engine load.

• If the cranks trigger signal fails to reach the

ECU, the engine will not run.

Figure 11.12

M48 Tank

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• Crank triggers are generally an all-or-nothing

proposition: they work perfectly or not at all. In

extremely rare instances, a failed crankshaft trig-

ger will not keep-up with the speed of the

engine. It will work at low speed, but cause

intermittent ignition and injector action at higher

speeds. This will result in staccato misses and

backfires.

11.15. The exhaust gas oxygen (O2) sensor contains a

palladium insert. When oxygen passes by palla-

dium, an electrical current is generated.

Depending on the amount of oxygen flowing by

the sensor, it will generate between 0.10 and

1.00 volts. See Figure 11.15.

• By measuring the amount of oxygen in the

exhaust gas, the ECU knows how much air is

passing through the engine un-burned. It can

make adjustments to the injector pulse length to

adjust the mixture until the ideal fuel air propor-

tions are reached. This ratio is known as “sto-

chiometric ratio” and is theoretically 14.7 parts

air to 1 part fuel (14.7:1).

• Adjustments the ECU makes to the fuel/air mix-

ture are the result of what is called “closed loop”

operation. The ECU is getting feedback on its

performance from the oxygen sensor, and mak-

ing adjustments based on that feedback.

• Oxygen sensors do not work below about 700

deg. F (375 deg. C). Because of this the engine

will not go into closed-loop operation until it is

warmed-up.

• Because of inconsistent gas flow at idle speed,

most engines fall out of closed-loop operation at

idle speed.

Figure 11.15

• Reaching a conclusion from the previous two

bullet points, a bad oxygen sensor will not cause

idle problems or cold-running problems.

• There is only one wire on the oxygen sensor

used in this application. It does not have a heat-

ing element in it, nor does it have a ground wire.

Some automotive applications have both of

these features. Because it does not have a

ground wire, it grounds through the body of the

sensor, and back through the engine exhaust

system.

• Oxygen sensors are susceptible to contamina-

tion from: leaded fuel, some RTV silicone seal-

ants, some cleaning solvents. Look for the

words “02 Sensor safe” on any of these products

to be introduced up-stream of the oxygen sen-

sor.

11.16. Oxygen sensors can be easily tested using a

good quality, high impedance DVOM or an oscil-

loscope.

• Engine turned off, hot sensor (normal operating

temperature) should have a resistance from the

disconnected wire to the housing or 2.0KΩ.

Cold sensor should have a resistance of 1.0MΩ.

• Engine running, (above idle speed) voltage mea-

sured from the disconnected wire (remember, do

not disconnect or connect an wires while the

engine is running), should fluctuate between 0.1

volt and 1.0 volt. This roughly approximates a

sine-wave on on oscilloscope. A “blip” of the

throttle should produce a momentary increase in

voltage as the engine leans-out slightly then re-

established correct mixture.

• A steadily declining voltage that recovers from a

throttle blip without fluctuating may indicate an

improperly positioned TPS.

11.17. This is a simplified introduction to the EFI sys-

tem used on the Kohler engine found on the

TANK. Complete diagnostic and service instruc-

tions can be found in the Kohler CH26 manual,

section 5B.