MTD 131-498A User manual

ASSEMBLY • OPERATION • MAINTENANCE • PARTS
38" LAWN TRACTOR
Important:
Read Safety Rules and
Instructions Carefully
Thank you for purchasing an
American built product.
Model Number
131-498A
PRINTED IN U.S.A.
FORM NO. 770-0863

I
INDEX
Safe Operation Practices.3
Assembly Instructions.4
Battery Information.5
Controls.8
Operation.10
Adjustments.12
Lubrication. 1 4
Maintenance .15
Off-Season Storage.19
Trouble Shooting Chart.20
Illustrated Parts for R.H. Side of Tractor.22
Parts List for R.H. Side of Tractor .23
Illustrated Parts for L.H. Side of Tractor.24
Parts List for L.H. Side of Tractor.25
Illustrated Parts for Frame View.26
Parts List for Frame View.27
Illustrated Parts for Deck View.28
Parts List for Deck View.29
Illustrated Parts forTransaxle.30
Parts List for Transaxle.31
Electrical Diagram.32
Deck Linkage.33
Parts Information..Back Cover
LIMITED WARRANTY
For one year from the date of original retail purchase, MTD PRODUCTS INC will either
repair or replace, at its option, free of charge, F.O.B. factory or authorized service firm,
any part or parts found to be defective in material or workmanship. Transportation charges
for any parts submitted for replacement under this warranty must be paid by the purchaser
unless such return is requested by MTD PRODUCTS INC.
This warranty will not apply to any part which has become inoperative due to misuse,
excessive use, accident, neglect, improper maintenance, alterations, or unless the unit
has been operated and maintained in accordance with the instructions furnished. This
warranty does not apply to the engine, motor, battery, battery charger or component parts
thereof. Please refer to the applicable manufacturer’s warranty on these items.
This warranty will not apply where the unit has been used commercially.
Warranty service is available through your local authorized service dealer or distributor. If
you do not know the dealer or distributor in your area, please write to the Customer Service
Department of MTD.
The return of a complete unit will not be accepted by the factory unless prior written
permission has been extended by MTD.
This warranty gives you specific legal rights. You may also have other rights which vary
from state to state.
TO PURCHASERS
OF INTERNAL COMBUSTION ENGINE EQUIPPED
MACHINERY OR DEVICES IN THE STATE OF CALIFORNIA
The equipment which you have just purchased does not have a spark arrester. If this equipment is used on
any forest covered land, brush covered land, or grass covered unimproved land in the State of California,
before using on such land, the California law requires that a spark arrester be provided. In addition, spark
arrester is required by law to be in effective working order. The spark arrester must be attached to the
exhaust system and comply with Section 4442 of the California Public Resources Code.
2

^ WARNING J
To reduce the potential for any injury, comply with the following safety instructions. Failure to comply with
the instructions may result in personal injury.
SAFE OPERATION PRACTICES FOR RIDING VEHICLES
1. It is suggested that this manual be read in its
entirety before attempting to assemble or
operate this unit. Keep this manual in a safe
place for future reference and for ordering
replacement parts.
2. This unit is a precision piece of power equip¬
ment, not a plaything. Therefore exercise ex¬
treme caution at all times.
3. Know the controls and how to stop quickly—
READ THIS OWNER’S MANUAL.
4. Do not allow children to operate vehicle. Do
not allow adults to operate it without proper
instruction. Only persons well acquainted
with these rules of safe operation should be
allowed to use your mower.
5. Do not carry passengers.
6. Keep the area of operation clear of all per¬
sons, particularly small children and pets.
Stop engine when they are in the vicinity of
your mower. Although the area of operation
should be completely cleared of foreign ob¬
jects, a small object may have been over¬
looked and could be accidently thrown by the
mower in any direction and cause injury.
7. Clear work area of objects which might be
picked up and thrown by the mower in any
direction and cause injury.
8. Stop the blade(s) when crossing gravel drives,
walks or roads.
9. Disengage all attachment clutches and shift
into neutral before attempting to start engine.
10. Disengage power to attachment(s) and stop
engine before leaving operating position.
11. Do not put hands or feet near or under rotating
parts. Keep clear of the discharge opening at
all times as the rotating blade(s) can cause in¬
jury. i
12. Disengage power to attachment(s) and stop
engine before making any repairs or ad¬
justments. Disconnect the spark plug wire
and keep the wire away from the plug to pre¬
vent accidental starting.
13. Before attempting to unclog the mower or
discharge chute, stop the engine. The mower
blade(s) may continue to rotate for a few
seconds after the engine is shut off.
Therefore, be sure the blade(s) have stopped
completely. Disconnect the spark plug wire
and keep the wire away from the plug to pre¬
vent accidental starting.
14. Disengage power to attachment(s) when
transporting or not in use.
15. Take all possible precautions when leaving
vehicle unattended such as disengaging
power-take-off, lowering attachments, shift¬
ing into neutral, setting parking brake, stop¬
ping engine and removing key.
16. Do not stop or start suddenly when going
uphill or downhill. Mow up and down face of
steep slopes; never across the face.
17. Reduce speed on slopes and in sharp turns to
prevent tipping or loss of control. Exercise ex¬
treme caution when changing direction on
slopes.
18. Stay alert for holes in terrain and other hidden
hazards.
19. Use care when pulling loads or using heavy
equipment.
A. Use only approved drawbar hitch points.
B. Limit loads to those you can safely control.
C. Do not turn sharply. Use care when back¬
ing.
D. Use counterweight(s) or wheel weights
when suggested in owner’s manual.
20. Watch out for traffic when crossing or near
roadways.
21. When using any attachments, neverdirect dis¬
charge of material toward bystanders nor
allow anyone near vehicle while in operation.
22. Handle gasoline with care. It is highly flam¬
mable.
A. Use approved gasoline container.
B. Never remove cap or add gasoline to a run¬
ning or hot engine or fill fuel tank indoors.
Wipe up spilled gasoline.
C. Open doors if engine is run in garage. Ex¬
haust fumes are dangerous. Do not run
engine indoors.
23. Keep the vehicle and attachments in good
operating condition, and keep safety devices
in place. Use guards as instructed in owner’s
manual.
24. Keep all nuts, bolts, and screws tight to be
sure the equipment is in safe working condi¬
tion.
25. Never store the equipment with gasoline in
the tank inside a building where fumes may
reach an open flame or spark. Allow engine to
cool before storing in any enclosure.
26. To reduce fire hazard, keep engine free of
grass, leaves or excessive grease.
27. The vehicle and attachments should be
stopped and inspected for damage after strik¬
ing a foreign object. The damage should be
repaired before restarting and operating the
equipment.
28. JDo not change the engine governor settings
or overspeed the engine.
29. When using the vehicle with mower, proceed
as follows:
(1) Mow only in daylight or in good artificial
light.
(2) Never make a cutting height adjustment
while engine is running if operator must
dismount to do so.
(3) Shut the engine off and wait until the
blade comes to a complete stop before
removing the grass catcher.
(4) Check blade mounting bolts for proper
tightness at frequent intervals.
30. Check grass catcher bags frequently for wear
or deterioration. For safety protection, replace
only with new bag meeting original equipment
specifications.
31. Look behind to make sure the area is clear
before placing the transmission in reverse
and continue looking behind while backing
up.

ASSEMBLY
FIGURE 1.
NOTE
This unit is shipped WITHOUT GAS¬
OLINE or OIL. After assembly, see
operating section of this manual for
proper fuel and engine oil recom¬
mendations.
-«—Contents of Hardware Pack:
(See figure 1)
A (2) Plastic Wing Nuts
B (1) Battery Hold Down
C (2) Ignition Keys
D (1) Steering Wheel Cap
E (1) Hex Lock Nut 5/16-24 Thread
F (1) Belleville Washer
G (1) Steering Tube
H (2) Battery Hold Down Rods
I (2) HexBoltsV4-20x.50"Lg.
J (2) Lock Washers V 4 " I.D.
K (2) Hex Nuts i/4-20Thread
Loose Parts in Carton:
L (1) Steering Wheel (Not Shown)
M (1) Battery Pack (Not Shown)
Reference to right hand or left hand
side of machine is from the driver’s
seat facing forward.
1. Place the steering tube (G) over the steering
shaft. See figure 2.
FIGURE 2.
Belleville
Steering/
Wheel (L)
FIGURE 3.
2. Place the steering wheel (H) over steering
— shaft and steering tube. See figure 3.
3. Secure steering wheel (L) with belleville
washer (F) (cup side down) and hex lock nut
(E). See figure 3. A Vz" wrench is required.
4

FIGURE 4. _
BATTERY INFORMATION
A.
{warning (
Battery acid must be handled with great care
as it will blister the skin and damage clothing.
It is advisable to wear goggles, rubber gloves,
and a protective apron when working with it.
B. I f for any reason acid should be spattered in
the eyes, wash it out immediately with clean
cold water. Seek medical aid if discomfort con¬
tinues.
C. If acid gets on clothes, dilute it with clean
water first, then neutralize with dilute ammonia
water or a water solution of baking soda.
D. Since battery acid is corrosive to metals, do
not pour into any sink or drain. Rinse empty
electrolyte containers and mutilate before
discarding.
<D
} DANGER {
BATTERIES CONTAIN SULFURIC
ACID AND MAY CONTAIN EXPLO¬
SIVE GASES (when electrolyte has
been added).
A. Keep sparks, flame, cigarettes away.
B. Hydrogen gas is generated during charging
and discharging.
C. Ventilate when charging or using in enclosed
space.
D. When using a charger—to avoid sparks,
NEVER connect or disconnect charger clips to
battery while charger is turned on.
E. Always shield eyes and protect skin and
clothing when working near batteries.
ACTIVATING THE BATTERY
NOTE
If your battery is activated (elec¬
trolyte in the battery) and installed
in the unit, go directly to step 9.
1. Place the battery to be filled on a workbench.
Never activate a battery in the unit.
2. Remove the fill caps from all cells.
3. Fill each cell carefully using 1.265 specific
gravity electrolyte. Fill each cell to the top of
the separators. Do not overfill.
4.
5.
Let the battery sit for 20 minutes to allow the
chemical reaction to take place.
Charge the battery at a MAXIMUM RATE OF 5
AMPS until the specific gravity reads 1.265.
Use a hydrometer to check the specific gravi¬
ty.
CAUTION
An excessive rate of charge will
damage the battery.
6. Check the level of electrolyte. Adjust level to
bottom of split ring if necessary with elec¬
trolyte.
7. Replace fill caps.
5

I
8. Once the battery has been activated, never
add anything except distilled water or a good
grade of drinking water.
9. If your battery has been installed in your unit
at the factory:
A. Use a hydrometer to check the specific
gravity. The specific gravity should be
1.265 at 80° F.
B. If it is less, remove the fill caps and use a
battery charger to bring the specific gravi¬
ty up to 1.265. NEVER CHARGE AT MORE
THAN 5 AMPS.
C. Replace the fill caps.
D. The positive cable has been attached to
the positive terminal of the battery at the
factory. You only have to attach the
negative cable (grounded) to the negative
(Neg, N or -) terminal of the battery with a
hex head bolt, lock washer and nut.
MAINTENANCE OF BATTERY
1. Check electrolyte level periodically (at least
every two weeks). Keep the level to the split
rings. Use only distilled water or a good quali¬
ty drinking water. Never add acid or any other
chemicals to the battery after initial activa¬
tion.
2. The battery should be checked with a
hydrometer after every 25 hours of operation.
If the specific gravity is less than 1.225, the
battery should be recharged. Maximum
charge rate 5 AMPS.
3. Coat the terminals and exposed wire with a
thin coat of grease or petroleum jelly for
longer service and protection against corro¬
sion.
4. The battery should be kept clean. Any
deposits of acid should be neutralized with
soda and water. Be careful not to get this solu¬
tion in the cells.
5. Avoid tipping the battery. Even a “sealed” bat¬
tery will leak electrolyte when tipped.
STORAGE OF THE BATTERY
1. S tore the battery in the unit.
2. K eep the exterior of the battery clean,
especially the top. A dirty battery will
discharge itself.
3.
Check the battery with a hydrometer. The bat¬
tery must be stored with a full charge. A
discharged battery will freeze.
Specific Gravity
1.265
1.250
1.200
1.150
1.100
Freezing Point
-71° F.
-62° F.
-16° F.
5° F.
16° F.
CAUTION
All batteries discharge
storage.
during
4. Recharge battery whenever the specific gravi¬
ty is less than 1.225, before returning to serv¬
ice or every two months, whichever comes
first.
COMMON CAUSES FOR BATTERY FAILURE
1. Overcharging
2. Undercharging
3. Lack of water
4. Loose hold downs and/or corroded connec¬
tions
5. Excessive loads
6. Battery electrolyte substitutes
7. Freezing of electrolyte
These failures do not constitute
warranty.
BATTERY REMOVAL OR INSTALLATION
®
} WARNING {
When removing the battery, follow
this order of disassembly to prevent
your wrench from shorting against
the frame.
1. Remove the Negative cable.
2. Remove the Positive cable.
To install a battery:
1. Attach the Positive cable.
2. Attach the Negative cable.
JUMP STARTING
1. Attach the first jumper cable from the Positive
terminal of the good battery to the Positive
terminal of the dead battery.
2. Attach the second jumper cable from the
Negative terminal of the good battery to the
FRAME OF THE UNIT WITH THE DEAD BAT¬
TERY.
®
\ WARNING \
Failure to use this starting pro¬
cedure could cause sparking, and
the gases in either battery could ex¬
plode.
6

INSTALL BATTERY
1. P l ace end of small red wire (with fuse holder)
— into rubber boot with positive ( + ) cable. See
figure 5.
FIGURE 5.
2. Place the battery into the lawn tractor, so that
the negative (-) terminal on battery is to the
—left hand side. See figure 6.
3. Place the end of rubber drain tube (on battery)
into the fixed convoluted tube on lawn tractor.
See figure 6. Reference to illustration on bot¬
tom of page 32 may also help.
FIGURE 6.
4. Place the battery hold down (B) over battery.
—See figure 7.
5. Secure battery hold down (B) with two hold
down rods (H) and plastic wing nuts (A). See
figure 7.
FIGURE 7.

6. Fasten the positive ( + ) cable and small red
wire (with fuse holder) to the positive ( + ) bat¬
tery terminal. Secure with hex bolt (I), lock
washer (J) and hex nut (K). See figure 8.
7. Fasten the negative (-) cable to the negative
(-) battery terminal. Secure with hex bolt (I),
lock washer (J) and hex nut (K). See figure 8.
NOTE
Be sure both cables are tightened
securely.
FIGURE 8.
Termini
8. S l i de the rubber boot on the positive (+) cable
down cable over positive ( + ) battery terminal.
See figure 9.
FIGURE 9.
CONTROLS
a. Throttle Control. The throttle control is used
to regulate the engine speed and choke the
engine. The engine should be operated from
3 A to full throttle when operating the cutting
deck or snow thrower (optional). See figure 10.
b. Gear Shift Lever. The gear shift lever is used
to shift into one of five Forward Gears,
“NEUTRAL” or “REVERSE.”
c. Lift and Disengagement Lever. It is used to
raise the cutting deck. Pulling it all the way
back and locking it disengages the blades.
The engine will not start unless the lift and
disengagement lever is in the disengaged
position. See figure 10.
FIGURE 10.
8

d. Ignition Switch. The ignition switch is located
on the left side of the dashboard. See figure
10. Turn the key to the “START” position to
start the engine. When the engine is running,
let the key return to the “ON” position. To
stop the engine, turn the key to the left to the
“OFF” position and remove it to prevent ac¬
cidental starting.
e. Light Switch. Push the light switch in to turn
on the lights. The lights will only operate
when the engine is running. See figure 10.
f. Brake Indicator Light. The brake indicator
light is located on the dash panel. The brake
light turns on when the operator depresses
the brake pedal while the ignition is on.
CAUTION
This light indicates that the brake is
engaged. Operating the unit with
the brake engaged will result in
rapid brake wear and premature
brake failure.
g. Ammeter. The c.nmeter registers the rate of
battery charge or discharge. The ammeter
should register on the plus side (approximate¬
ly 3 amps) when the engine is running. With
the engine idling, the charging rate will be
less. See figure 10.
The headlights operate directly from the alter¬
nator and will not register on the ammeter.
h. Brake. The brake pedal is located on the right
hand side of the mower and is operated by
depressing it with your right foot. See figure
11 .
i. Brake Lock. The brake lock is located on the
right hand side of the mower. To lock the
brake, depress the brake pedal and lift up the
lock button. The pedal will stay depressed. To
release, depress the pedal. See figure 12.
FIGURE 12.
j. Clutch Pedal. The clutch pedal is used to
disengage the drive mechanism. Depressing
the clutch pedal at any time will reduce
mower speed. See figure 13.
FIGURE 13.
k.
Clutch Lockout. When the clutch pedal is
depressed all the way, it can be locked by
placing the clutch lockout in the “START”
position as shown in figure 14. The clutch
lockout must be in this position before the
engine will start.
NOTE
The engine will not start unless
the clutch lockout is in the
“START” position and the lift
lever is in the DISENGAGED posi¬
tion.
FIGURE 11.

FIGURE 14.
I. Cutting Controls. The cutting controls consist
of the height of cut stop and the wheel height
adjusters.
Height of Cut Stop. See figure 15. Lift the stop
and set it at the desired cutting height.
FIGURE 15.
Wheel Height Adjuster. See figure 16. Move the
lever towards the wheel and set it in the desired
cutting height.
FIGURE 16.
The cutting height of the mower can be set in two
different ways: FULL FLOAT position where the
deck follows the contour of the ground, and the
SUSPENDED position where the deck hangs from
the frame of the rider. The suspended position is
normally used for cutting rough uneven ground.
To set the cutting deck in the full float position,
set the wheel height adjusters in the desired cut¬
ting height as indicated in figure 15. Set height of
cut stop all the way forward. See figure 15.
To set the cutting deck in the suspended position,
set the height of cut stop in the desired cutting
height and then set the deck wheels so they just
clear the ground.
OPERATION
A
CAUTION
Keep all shields in place.
Before leaving operator’s position:
a. Shift transmission to neutral
b. Set parking brake
c. Disengage attachment clutch
d. Shut off engine
e. Remove ignition key
Wait for all movement to stop before
servicing machine.
Keep people and pets a safe distance
away from machine.
Look to the rear before backing up.
A
TIRE PRESSURE
FOR SHIPPING PURPOSES, THE TIRES ON YOUR
UNIT MAY BE OVER INFLATED. TIRE PRESSURE
SHOULD BE REDUCED BEFORE UNIT IS PUT IN¬
TO OPERATION. PRESSURE SHOULD BE AP¬
PROXIMATELY 15 P.S.I. EQUAL TIRE PRESSURE
SHOULD BE MAINTAINED ON ALL TIRES. MAX¬
IMUM TIRE PRESSURE IS 30 P.S.I.
CAUTION
Installation of tire to rim:
1. Lubricate tire beads and rim
flanges.
2. Do not exceed 30 P.S.I. when
seating beads.
3. Adjust to recommended pres¬
sure after beads are sealed.
10

STARTING THE ENGINE
1. Be sure to follow the instructions for the oil
and gasoline as described in the engine
manual.
2. Be sure the fuel shuft-off valve is open (must
be turned counterclockwise). See figure 17.
FIGURE 17. FUEL SHUT-OFF VALVE
3. Set parking brake and place shift lever in
neutral position.
4. Place the clutch lockout in the “START” posi¬
tion. See figure 14.
5. Place the lift and disengagement lever in the
DISENGAGED position. See figure 10.
NOTE
This unit is equipped with a safety
interlock system for your pro¬
tection. The purpose of the safety
interlock system is to prevent the
engine from cranking or starting
unless the clutch pedal is de¬
pressed and the lift and disen¬
gagement lever is in the disen¬
gaged position.
j WARNING {
Do not operate the rider if the inter¬
lock system is malfunctioning be¬
cause it is a safety device, designed
for protection.
6. Set the throttle control in the “CHOKE” posi¬
tion. See figure 10.
7. Turn the ignition key to the “START” position.
When the engine is running, let the key return
to the “ON” position. See figure 10.
STOPPING THE ENGINE
Turn the ignition key to the left to the “OFF” posi¬
tion. Remove the key to prevent accidental star¬
ting.
NOTE
A brief break-in period is essential
to ensure maximum engine and
mower life. This consists of running
the engine at half speed for a period
of time required to use one tank of
gasoline. It is also recommended to
change crankcase oil after the first 2
hours of operation.
IMPORTANT
After striking a foreign object, stop
the engine. Remove wire from spark
plug, thoroughly inspect the mower
for any damage, and repair the dam¬
age before restarting and operating
the mower.
OPERATING THE MOWER
1. Set the desired cutting height.
2. Start the engine.
3. Release parking brake.
CAUTION
Parking brake MUST be disengaged
before unit is put into motion.
4. Move throttle control to desired engine speed.
5. Depress the clutch pedal and shift into first
gear or reverse.
NOTE
DO NOT force the gear shift lever!
6. R elease clutch pedal slowly to put unit into
motion.
7. Depress the clutch pedal when shifting gears.
8. The mower is brought to a stop by depressing
the brake and clutch pedals. The drive belt will
be disengaged and the brake will be applied.
NOTE „
Unit is equipped with separate
brake and clutch pedals. It is neces¬
sary to disengage clutch when
applying brakes to stop.
CAUTION
If the mower is not to be used
for a long period, place the gear
shift lever in NEUTRAL and stop
the engine. DO NOT leave the
machine on an incline.
11

I
OPERATING THE CUTTER BLADE
The cutting blades may be engaged while the
mower is moving or standing still. DO NOT
engage the cutting blades abruptly as the sudden
belt tension on the pulley may cause the engine to
stall.
<D
{ WARNING {
When the blade drive is engaged,
keep feet and hands away from the
discharge opening and from the
blade.
To stop the blades, move the lift and disengage¬
ment lever (figure 14) into the DISENGAGED posi¬
tion. This raises the deck and disengages the
blades. .
NOTE
When the machine is used for other
than mowing operations, the blade
drive should be disengaged.
GRASS CATCHER Model No. 191-015A is
available as optional equipment for the mower
shown in this manual.
<D
| WARNING \
The mower should not be operated
without the entire grass catcher or
chute deflector in place.
NOTE
Under normal usage bag material is
subject to wear, and should be
checked periodically. Be sure any
replacement bag complies with the
mower manufacturer’s recom¬
mendations.
For replacement bags, use only fac¬
tory authorized replacement bag
No. 764-0121.
ADJUSTMENTS
SEAT ADJUSTMENT
Your seat may be adjusted in one of four hole loca¬
tions. Remove hex bolts and lock washers from
under seat spring.
After desired seat location is selected, secure
seat to seat spring with lock washers and hex
bolts. A 3/4" or adjustable wrench is required. See
figure 18.
Hlles in Seat
* Spring
FIGURE 18.
BRAKE ADJUSTMENT
During normal operation of this machine, the
brake is subject to wear and will require periodic
examination and adjustment.
CAUTION
Do not have the engine running
when you adjust the brakes.
FIGURE 19.
1. Move the brake pedal forward by hand until
resistance is noted. This is the point where
the brake pedal spring begins to stretch.
2. If the adjustment is correct, the brake lock
should move Va inch. See figure 19.
3. If adjustment is necessary, tighten or loosen
the brake adjusting nuts until the correct
dimension is obtained. See figure 20. Periodic
adjustment is necessary to maintain effective
brake operation.
12

FIGURE 20.
WHEEL ADJUSTMENT
The caster (forward slant of the king pin) and the
camber (tilt of the wheels out at the top) require no
adjustment. Automotive steering principals have
been used to determine the caster and camber on
the tractor. The front wheels should toe-in 1/8
inch.
To adjust the toe-in, follow these steps.
1. R emove the elastic lock nut and drop the tie
rod end from the wheel bracket. See figure 21.
C.) Reassemble tie rod. Check dimensions. Read¬
just if necessary.
FIGURE 22. TOE-IN DIAGRAM
NOTE
To insure safe operation of your
unit, ALL nuts and bolts must be
checked periodically for correct
tightness.
CARBURETOR ADJUSTMENTS (See figure 23)
FIGURE 21.
2. Loosen the hex jam nut on tie rod.
3. Adjust the tie rod assembly for correct toe-in.
Dimension “B” should be approximately 1/8" less
than Dimension “A.” See figure 22.
A. ) To increase Dimension “B,” screw tie rod into
tie rod end.
B. ) To decrease Dimension “B,” unscrew tie rod
from tie rod end.
<L WARNING \
If any adjustments are made to the
engine while the engine is running
(e.g. carburetor), disengage all
clutches and blades. Keep clear of
all moving parts. Be careful of
heated surfaces and muffler.
Minor carburetor adjustment may be required to
compensate for differences in fuel, temperature,
altitude and load.
To Adjust Carburetor— T u r n needle valve
clockwise until it just closes.
CAUTION
Valve may be damaged by turning
it in too far.
Now open needle valve 1-1/8 turns counterclock¬
wise. Close idle valve in same manner and open
1-1/8 turns. This initial adjustment will permit the
engine to be started and warmed up prior to final
adjustment.
13

I
Final Adjustment— Turn needle valve in until
engine misses (lean mixture). Then turn it out past
smooth operating point until engine runs eneven-
ly (rich mixture). Now turn needle valve to the mid¬
point between rich and lean so the engine runs
smoothly. Hold throttle at idle position and set
idle speed adjusting screw until fast idle is ob¬
tained (1750 RPM). Hold throttle in idle position
and turn idle valve in (lean) and out (rich) until
engine idles smoothly. Then reset idle speed ad¬
justing screw so that engine idles at 1750 RPM.
Release throttle—engine should accelerate
without hesitation or sputtering. If engine does
not accelerate properly, the carburetor should be
readjusted to a slightly richer mixture.
ADJUSTING CARBURETOR CHOKE
Proper choke adjustment is dependent upon prop¬
er adjustment of remote controls on the powered
equipment.
To Check Operation of Choke-A-Matic Controls:
Move control lever to “CHOKE” position. See
figure 10. The carburetor choke should be closed.
NOTE
The air cleaner can be removed to
check the operation of the choke.
To Adjust:
Place control lever on equipment in FAST (high
speed) position. Loosen control casing clamp
screw B. Move control casing A and wire until
lever D touches choke operating link at C. Tighten
casing clamp screw B. See figure 24.
LUBRICATION
1. Wheel Bearings (4). Lubricate with SAE 30 oil
after every 25 hours of operation or once a
season. See figure 25.
2. King Pins (2). Lubricate with SAE 30 oil after
every 25 hours of operation or once a season.
See figure 25.
3. Front Pivot Bolt (1). Lubricate with SAE 30 oil
after every 25 hours of operation or once a
season. See figure 25.
FIGURE 25.
4. Steering Gears (2). Lubricate teeth of gears
with automotive multi-purpose grease after
every 25 hours of operation or once a season.
See figure 26.
5. Steering Column Bearings (2). Lubricate the
top and bottom bearings with SAE 30 oil after
every 25 hours of operation or once a season.
See figure 26.
6. Steering Shaft Bearings (2). Require no
lubrication. See figure 26.
14

FIGURE 26.
7. Transaxle. The transaxle is sealed at the fac¬
tory and does not require checking. If
disassembled for any reason, lubricate with
24 oz. of EP Lithium grease. See figure 27.
The following parts should be oiled once a year
with SAE30oil.
1. All deck links.
2. Clutch and brake pivot points and linkages.
3. Height adjustment levers.
4. Steering column bearings.
The following items have sealed bearings and re¬
quire no further lubrication.
1. Blade Spindles
2. Idler Bearings
3. Tie Rod Ends
MAINTENANCE
CRANKCASE OIL
To ensure maximum engine performance, perform
the following periodic maintenance:
Oil Check
Check the oil level in the crankcase before each
use of the machine and after every five hours of
operation. Oil should be kept between the add and
full marks on the dipstick. See figure 28.
FIGURE 28.
After the first five hours of operating a new
engine, drain the oil (see figure 29) from the
crankcase while engine is still hot and refill
crankcase with new oil; thereafter change the oil
every 25 hours of operation. This procedure en¬
sures minimum wear of engine parts. To change
the oil, proceed as follows:
1. With the machine on level ground, place a
suitable metal container under the oil drain
plug, then remove the drain plug. See figure
29.
FIGURE 29.
2. After the oil has been drained completely
from the crankcase, replace the drain plug and
tighten.
15

I
3. Refill crankcase with 2V4 pints of good quali¬
ty, type MS, engine oil into the crankcase.
Summer use SAE 30; Winter (below 40° F) use
SAE 5W-20 or SAE 10W.
AIR CLEANER
Under normal operating conditions, the air
cleaner, located on top of the carburetor, must be
serviced after every ten hours of use. Under ex¬
tremely dusty operating conditions, the air
cleaner must be serviced after every hour of
operation. Refer to figure 30.
FIGURE 30.
When assembling the air cleaner, make certain
the lip of the foam element extends over edge of
the air cleaner body. The foam element will form a
protective seal.
Step 1. Remove two screws and lift off complete
air cleaner assembly.
Step 2. Remove screen and spacers from foam
element.
Step 3. Remove foam element from air cleaner
body.
Step 4. a. Wash foam element in kerosene or liq¬
uid detergent and water to remove dirt.
b. Wrap foam in cloth and squeeze dry.
c. Saturate foam in SAE 30 engine oil,
then squeeze out excess oil.
d. Assemble parts. Fasten to carburetor
with screw.
CLEANING ENGINE AND BLADE HOUSING
Any fuel or oil spilled on the machine should be
wiped off promptly. Grass, leaves, and other dirt
must not be left to accumulate around the cooling
fins of the engine or on any part of the machine.
Clean the underside of the blade housing after
each mowing.
BELTS
Check that belts are free of oil or dirt. Wipe the
belts periodically with a clean rag.
NOTE
Belt tension is maintained by the
spring on the idler bracket on the
drive belts and the belt tension on
the deck belt is maintained by the
two deck springs.
SPARKPLUG
The spark plug should be cleaned and the gap
reset to a 0.030-inch clearance once a season (see
figures 31 and 32). Spark plug replacement is
recommended at the start of each mowing
season; check engine parts list for correct plug
type.
NOTE
Whenever the spark plug is removed
for cleaning, it is advisable to re¬
place the spark plug gasket with a
new gasket.
FIGURE 31.
FIGURE 32.
16

REPLACING BLADE
( WARNING {
Before beginning work on the cutter
blade, remove the spark plug from
the cylinder.
Removing and Sharpening Blades. Remove the
center bolt and lock washer. See figure 33. Pull
the blade and blade adapter from the blade spin¬
dle.
The adapter can be removed from the blade by
removing the two adapter bolts, lock washers and
nuts.
To insure safe operation of your
unit, ALL nuts and bolts must be
checked periodically for correct
tightness.
BELT REMOVAL AND REPLACEMENT
Preparation
<£>
( WARNING }
Disconnect the spark plug wire and
ground it against the engine.
1. R emove the battery.
CAUTION
Disconnect the negative terminal
first and connect last when in¬
stalling the battery.
2. To prevent gasoline from leaking from the
engine, remove the gasoline cap, place a
piece of thin plastic over the neck of the
gasoline tank and screw on the cap.
3. Close the fuel shut-off valve.
4. Set the brake and lock it.
5. Lift the front end of the rider up and rest it on
the rear wheels. It will balance in this position.
6. Secure with rope to prevent tipping.
\7. Do not leave the rider in this position any
longer than necessary as oil may get into the
cylinder head. If this happens, remove the
spark plug and crank over the engine to clear
the oil.
Removing the Deck Belt
1. Place the lift lever in the disengaged position.
2. Remove the belt keeper and large bolt from
the engine pulley. See figure 34.
FIGURE 34.
3. Unhook the deck belt from the engine pulley.
4. Place the lift lever in the engaged position.
5. Remove the two deck tension springs. See
figure 35.
6. Remove the cotterpins holding the four front
deck links. The deck can now be tipped for¬
ward. See figure 35,
7. Remove the belt guard on the left deck pulley
by removing the two bolts and nuts.
8. Remove the three shoulder bolts and washers
next to the right deck pulley.
17

FIGURE 37.
3. Remove the belt keeper and large bolt from
the engine pulley. See figure 34.
4. Unhook the deck belt from the engine pulley.
5. Place the lift lever in the engaged position.
6. Unhook the tension springs. See figure 35.
7. Remove the six cotter pins holding the deck
to the links.
8. Lift off the deck and set it aside.
9. Remove the engine belt guard by removing
the two front engine mounting bolts. See
figure 36.
10. Remove the wire belt keeper on frame. See
figure 36.
11. Slide belt off the V-idler and remove.
12. Unhook the belt from the engine pulley. See
figure 37.
13. Replace the belt and reassemble in reverse
order.
CAUTION
Be sure to remove plastic from be¬
neath gasoline cap.
9. Remove and replace the deck belt. Reassem¬
ble in reverse order.
CAUTION
Be sure to remove plastic from be¬
neath gasoline cap.
FIGURE 35.
Removing the Transmission Belt
1. Follow steps 1 through 6 on Preparing for Belt
Removal.
2. Place the lift lever in the disengaged position.
FIGURE 36.
18

OFF SEASON STORAGE
If the machine is to be inoperative for a period
longer than 30 days, the following precautions are
recommended:
1. W orking outdoors, drain ail fuel from the fuel
tank. Use a clean dry cloth to absorb the small
amount of fuel remaining in the tank, then run
the engine until all fuel in carburetor is ex¬
hausted.
<£>
\ WARNING {
Do not drain fuel while smoking, or
if near an open fire.
2. Drain all the oil from the crankcase (this
should be done after the engine has been
operated and is still warm) and refill the
crankcase with clean new oil.
3. Disconnect the spark plug wire and remove
the spark plug from the cylinder. Pour about
six drops of engine oil into the cylinder, and
then pull the recoil starter several times to
spread the oil on the cylinder wall. Replace
the spark plug, but DO NOT connect the wire.
4. Clean the engine and the entire mower
thoroughly.
5. Lubricate all lubrication points indicated in
figures 25, 26 and 27. Then wipe the entire
machine with an oiled rag in order to protect
the surfaces.
19

TROUBLE SHOOTING CHART FOR ELECTRIC START MODELS
TROUBLE LOOK FOR
REMEDY
Engine will not
crank
Battery installed incor¬
rectly
The battery must be installed with the negative, identified at the terminal post by (Neg, N or -),
grounded. The positive (Pos, P or + ) attaches to the large cable from the solenoid. The small
red wire from the fuse holder or circuit breaker is also attached to the positive terminal.
Blow fuse or circuit
breaker
Replace fuse with 7 Vi amp. fuse V* x 1 'A" Ig. Circuit breaker will reset itself when it cools off.
Fuses or circuit breakers seldom open or fail without a reason. The problem must be corrected.
Check for loose connections in the fuse holder. Replace fuse holder if necessary. A dead short
may be in the cranking or charging circuit where the insulation may have rubbed through and
exposed the bare wire. Replace the wire or repair with electrican’s tape if the wire strands have
not been damaged. Note: Look for a wire pinched between body panels, burned by the ex¬
haust pipe or muffler or rubbed against a moving part.
Battery is dead or weak
Use a hydrometer to check the condition of the battery. The Specific Gravity (s.g.) should be
1.265 at 80°F. (1.215 s.g. minimum needed for cranking engine). The reason for the battery fail¬
ing must be determined. (1) Defective battery. Battery will not accept or hold a full charge. (2)
Short circuit. Check for grounded wire. (3) Charging system not working, either engine alter¬
nator or trickle charger.
Trickle Charger. Check with multimeter. Charger 725-0578—input 120 V A.C., no load output
13.5 V D.C. rated load current 1 amp. Charger 725-0507—input 120 V A.C., no load output 17.4 V
D.C., rated load current 1/2 amp.
Alternator (dual or single circuit) The charging system is an alternator located under the
flywheel. It is unregulated and rated 3 amp. at 3600 r.p.m. A diode (rectifier) is located in the
output lead just before the wire harness plug on the engine side.
To Alternator
The diode changes A.C. to D.C. to charge the battery. A bad diode can either fail to charge the
battery or discharge the battery if the alternator is shorted as well as the diode. To test: (1)
Disconnect charger lead from the battery (small red wire). (2) Connect 12 V small test lamp bet¬
ween the 3 amp. D.C. charge lead and the positive terminal of the battery. (3) With the engine
off, the lamp should not light. If it does, the diode and possibly the alternator should be replac¬
ed. (4) Start the engine. The lamp should light. If it does not,the alternator (stator) or lead wire
is bad and should be replaced.
Mechanical failure.
(Wires and switches)
The interlock system includes two mechanical activated switches which are wired in series in
the circuit used to energize the starter solenoid. While testing the interlock system, you will
make the mower temporarily unsafe by permitting the engine to be started with the blade and
clutch engaged. WARNING: While testing, disengage the clutch, shut off the blade control, set
the parking brake and place the gear shift lever in neutral. Attach a wire (minimum 18 gauge) to
the positive terminal of the battery and touch the other end to the small terminal on the
solenoid. If the engine does not crank: (1) There is a loose connection or poor ground. (2) The
solenoid may be bad. The solenoid can be checked by using a heavy wire (#8 gauge minimum)
and jumping between the two large terminals. If the engine cranks, the solenoid is bad. (3) If
the engine does not crank when you jump the solenoid, have the starter motor tested by an
authorized engine dealer. If the engine does crank, the problem is with one of the safety swit¬
ches, ignition switch or the wire between the fuse holder (or circuit breaker) and the small ter¬
minal on the solenoid. Note: Look for a poor connection at the switches or a defective switch.
Replace if necessary.
Engine cranks
but will not
start
Throttle or choke not in
starting position
Check owner’s guide for correct position for throttle control and choke (if separate control) for
starting.
20