MTD 137-496A User manual

TEN CENTS
• assembly Model No.
• OPERATION 137-496A
• MAINTENANCE
• PARTS LIST
Important:
Read Safety Rules and
Instructions Carefully

I
■ ^IMPORTANT
It is suggested that this manual be read in its entirety before attempting to assemble or operate. Keep this
manual in a safe place for future reference and for ordering replacement parts.
This unit is shipped WITHOUT GASOLINE or OIL. After assembly, see operating section of this manual for
proper fuel and amount.
Your rotary mower is a precision piece of power equipment, not a plaything. Therefore exercise extreme
caution at all times.
SAFE OPERATION PRACTICES FOR RIDING VEHICLES
1 Know the controls and how to stop quickly—
READTHE OWNER’S MANUAL.
2. 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.
3. Do not carry passengers.
4. Keep the area of operation clear of all
persons, 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
objects, a small object may have been over¬
looked and could be accidently thrown by the
mower in any direction.
5. Clear work area of objects which might be
picked up and thrown by the mower in any
direction.
6. Disengage all attachment clutches and shift
into neutral before attempting to start engine.
7. Disengage power to attachment(s) and stop
engine before leaving operator position.
8. Disengage power to attachment(s) and stop
engine before making any repairs or adjust¬
ments. Disconnect the spark plug wire and
keep the wire away from the plug to prevent
accidental starting.
9. Before attempting to unclog the mower or
discharge chute, stop the engine and be sure
the blade(s) have stopped completely. Dis¬
connect the spark plug wire and keep the wire
away from the plug to prevent accidental
starting.
10. Disengage power to attachment(s) when
transporting or not in use.
11 . Take all possible precautions when leaving
vehicle unattended such as disengaging
power-take-off, lowering attachments, shift¬
ing into neutral, setting parking brake,
stopping engine and removing key.
12. Do not stop or start suddenly when going
uphill or downhill. Mow up and down face of
steep slopes; never across the face.
13. Reduce speed on slopes and in sharp turns to
prevent tipping or loss of control. Exercise
extreme caution when changing direction on
slopes.
14. Stay alert for holes in terrain and other hidden
hazards.
15. 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
backing.
D. U s e counterweight(s) or wheel weights
when suggested in owner’s manual.
16. Watch out for traffic when crossing or near
roadways.
17. When using any attachments never direct dis¬
charge of material toward bystanders nor
allow anyone near vehicle while in operation.
18. Handle gasoline with care—it is highly
flammable.
A. Use approved gasoline container.
B. Never remove cap or add gasoline to a
running or hot engine or fill fuel tank
indoors. Wipe up spilled gasoline.
C. Open doors if engine is run in garage-
exhaust fumes are dangerous. Do not run
engine indoors.
19. Keep the vehicle and attachments in good
operating condition, and keep safety devices
in place. Use guards as instructed in owner’s
manual.
20. Keep all nuts, bolts, and screws tight to be
sure the equipment is in safe working condi¬
tion.
21. 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.
22. To reduce fire hazard keep engine free of
grass, leaves or excessive grease.
23. The vehicle and attachments should be
stopped and inspected for damage after
striking a foreign object, and the damage
should be repaired before restarting and
operating the equipment.
24. Do not change the engine governor settings or
overspeed the engine.
25. 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.
26. Check grass catcher bags frequently for wear
or deterioration. For safety protection replace
only with new bag meeting original equip¬
ment specifications.
27. Look behind to make sure the area is clear
before placing the transmission in reverse and
backing up.

INDEX
Safe Operation Practices.2
Assembly.3
Battery Information. 4
Installing the Battery.5
Controls.6
Operating Instructions.8
Maintenance. 9
Lubrication. 10
Adjustments. 1 1
Belt Replacement. 1 3
Off-Season Storage. 14
Trouble Shooting Chart. 1 5
Transaxle. ^
Repair Parts. 18
Wiring Diagram.26
Parts Information.Back Cover
IMPORTANT
After striking a foreign object, stop the
engine. Remove wire from spark plug,
thoroughly inspect the mower for any
damage, and repair the damage be¬
fore restarting and operating the
mower.
The steering wheel and seat, with the necessary hard¬
ware, are easily assembled to the machine. The battery
must be activated and installed as outlined in this sec¬
tion.
TIRE PRESSURE
r'T— —V\
V—4
Hex Nut Vi-13 Thd.
D
Spring Lockwasher
'/a" Screw
F
(ED
Hex Lock Nut 5/16-18Thd.
FOR SHIPPING PURPOSES, THE TIRES ON YOUR UNIT
MAY BE OVER-INFLATED. TIRE PRESSURE SHOULD BE
REDUCED BEFORE UNIT IS PUT INTO OPERATION.
PRESSURE SHOULD BE APPROXIMATELY 15 P.S.I.
EQUAL TIRE PRESSURE SHOULD BE MAINTAINED ON
ALL TIRES. MAXIMUM 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 seat¬
ing beads.
3. Adjust to recommended pressure
after beads are sealed.
Belleville Washer
G
Wing Nut Vi-20
H
o
Lockwasher
Hex Nut Vi " Screw
Vi-20 Thd.
FIGURE 1. HARDWARE SUPPLIED
rrn
Hex Bolt
Vi-20 x 5/8
ASSEMBLY
Step 1. Remove the lawn mower and all parts from
the carton. Make certain that all loose parts
and literature have been removed before the
carton is discarded.
Reference to right-hand or left-hand
side of machine is from the driver's
seat facing forward.
Step 2. Place steering wheel over steering shaft.
Step 3. Secure with Belleville Washer (E) and Hex Nut
(F). See figure 2.
Step 4. Press the cap on the steering wheel by hand.
See figure 2.
3

I
Steering Wheel Cap
Hex Nut-
Belleville Washer-
F
■ E
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. Neutralize acid spilled on clothing with dilute am¬
monia water or a water solution of baking soda. If
acid gets on clothes, dilute it with clean water first,
then neutralize.
C. If for any reason acid should be spattered in the
eyes, wash it out immediately with clean cold
water. Seek medical aid if discomfort continues.
FIGURE 2 . STEERING WHEEL ASSEMBLY
Step 5. Use the hex nut and lockwasher to attach the
seat to the seat spring in one of the three
adjustment holes. (See figure 3.)
FIGURE 3.
Check ALL nu'» and bolts for correct
tightness.
D.
Since battery acid is corrosive to metals, do not
pour into any sink or drain. Rinse empty electro¬
lyte containers and mutilate beto r e discarding.
^ WARNING J
BATTERIES CONTAIN SULFURIC ACID
AND MAY CONTAIN EXPLOSIVE
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, protect skin and clothing
when working near batteries.
A. Activating the Battery
1. Place the battery to be filled on bench or work¬
bench. NEVER activate battery in unit. Remove
vent caps from all cells.
2. Fill each cell carefully using battery grade
1.250-1.265 specific gravity. Sulfuric acid to be
3/8" above the top of the separators or to the
split ring.
3. Allow battery to set for 20 minutes to 'A hour.
. Add additional acid if necessary to bring it up to
the proper level.
4. Replace the venl^ caps.
4

5. T he battery can now be charged after the 20
minutes setting period. Battery can be SLOW
CHARGED (DO NOT FAST CHARGE) at G
maximum bench rate of 4-5 amperes until the
specific gravity reading is 1.265-1.275. A
charging rate in excess of this wifi buckie and
warp the positive plates end perforate the
separators, if electrolyte hubbies violently while
charging, reduce charging rate until excessive
bubbling action subsides, then continue charging
until specific gravity is reached.
CAUTION
After battery has been in service, add
only approved water. DO NOT ADD
AGD.
3. To install Battery
To install the battery in this unit, refer to next column.
C. Maintenance
1. Check periodically (every two weeks or before
and after charging) to be sure electrolyte level is
9/16” above separator plates. Add only distilled
water or good quality drinking water. NEVER add
additional acid or other chemicals to battery after
initial activation.
2. The battery should be checked with a hydrometer
after every 25 hours of operation. If the specific
gravity is less than 1.225 remove battery and
recharge.
3. Coat the terminals and exposed wiring with a thin
coat of grease or petroleum jelly for longer
service and protection against electrolyte 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 solution in the cells.
D. Storage
1. Charge battery using normal methods. NEVER
store discharged battery as it will not recover.
2. Store in cold, dry place.
3. Recharge battery whenever the specific gravity is
less then 1.225 before returning to service or
every two months, whichever occurs first.
E. Common Causes for Battery Failure Are:
1. Overcharging
2. Undercharging
3. Lack of wester
4. Loose hold downs and/or corroded connections
7 . Excessive loads
6. Battery electrolyte substitutes
7. Freezing of electrolyte
THESE FAILURES DO NOT CONSTITUTE
WARRANTY.
LIMITED WARRANTY
For ninety (90) days of original retail purchase, the
' . Ts-ry carries a limited warranty against faulty
material or workmanship by the battery manufact-
1. Open the hood of the riding mower,
2, Place the battery in the battery case with the ter¬
minal to the front. See figure 4.
FIGURE 4.
3. Cut the black rubber tubing approximately 4 inches
long.
4. Push the rubber tubing into the manifold of the
battery and place the other end into the drain tube.
See figures 4 and 5.
NOTE
The vented battery allows any gases or
liquid from the battery to be carried to
the rear of the mower through the
drain tube.
5

Hold Down Rod
Throttle
Control
5. Hook the hold down rods under the battery case
and place the hold down over the manifold of the
battery as shown in figure 6.
6. Secure the hold down with the wing nuts.
CONTROLS
The controls on both models may be considered as the
Drive Control and the Cutting Control as follows:
a Throttle Control. The throttle control is used to regu¬
late the engine speed and choke the engine. The en¬
gine should be operated from 3 A to full throttle when
operating the cutting deck or snow thrower (optional).
See figure 7.
b. G ear Shift Lever. The gear shift lever is used to
shift into one of three FORWARD GEARS, NEUTRAL or
REVERSE. See figures 7 and 8.
c. B rake. 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 9.
d. B rake 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 fig
ure 9.
e. C lutch Pedal. The clutch pedal is used to disengage
the drive mechanism. Depressing the clutch pedal at
any time will reduce mower speed. If depressed all the
way, it will stop the mower. See figure 10.
h. Light Switch. Pull the light switch out to turn on
the lights. The lights will only operate when the en¬
gine is running. See figure 7.
f. Clutch Lockout. When the clutch pedal is depressed
all the way it can be locked by placing the clutch lock¬
out in the START position as shown in figure 8. The
clutch lockout must be in this position before the en¬
gine will start.
g. Ammeter. The ammeter registers the rate of battery
charge or discharge. The ammeter should register on
the plus side { + ) when the engine is running in the
fast position until the battery is completely charged.
With a fully charged battery or with the engine idling
the ammeter will not show a charge. See figure 7.
7. A ttach the positive cable (from the starter solenoid)
and the small wire (from the ammeter) to the pos¬
itive battery terminal with the bolt, lockwasher and
nut in the assembly pack.
8. A ttach the negative cable, grounded, to the neg¬
ative battery terminal with the bolt, lockwasher
and nut in the assembly pack.
FIGURE 6
FIGURE 7 . CONTROLS
6

TRANSAXLE DRIVE
10 START
'Lock out clutch tty (top>eKsint) left
pedal S pulhnq knob up mm slat
o
• Set Ehiottie to choke .1 engine isc-oid
• Disenqaqe bladps
• Turn key lo Stan engine
FIGURE 9. RIGHT HAND CONTROLS
FIGURE 8. SHIFT PATTERN
i. Ignition Switch. The ignition switch is located on the
right side of the dashboard.
Electric Start. See figure 7. Turn the key to the START
pos't’on to start the engine. When the engine is run¬
ning, 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 accidental starting.
NOTE
The engine will not start unless the
clutch lockout is in the START position
and the lift lever is in the DISENGAGED
position.
i- 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 un¬
less the lift and disengagement lever is in the disen¬
gaged position. See figure 9.
FIGURE 10. LEFT HAND CONTROLS
FIGURE 11. HEIGHT OF CUT SETTINGS
k. Cutting Controls. The cutting controls consist of the
height of cut stop and the wheel height adjusters.
Height of Cut Stop. See figure 11. Lift the stop and set
it at the desired cutting height.
Wheel Height Adjuster. See figure 12. Move the lever
towards the wheel and set it in the desired cutting
height.
The cutting height of the mower can be set in two dif¬
ferent ways: FULL FLOAT position where the deck fol¬
lows 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 cut¬
ting rough uneven ground.
7

I
To set the cutting deck in the fui! float position, set the
wheel height adjusters in the desired cutting height as
indicated in figure 12. Set height of cut stop in the
1 Vi position. See figure 11.
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 wheel so they just dear the ground.
FIGURE 12. WHEEL HEIGHT ADJUSTER
OPERATING
INSTRUCTIONS
STARTING THE ENGINE
Be sure to follow the instructions for the oil and gaso¬
line as described in the engine section of this manual.
Step 1. Be sure the fuel shut-off valve is open. See
figure 13.
FIGURE 13. FUEL SHUT-OFF VALVE
Step 2. Place the clutch lockout in the START position.
See figure 10.
Step 3. Place the lift and disengagement lever in the
DISENGAGED position. See figure 9.
Step 4. Set the throttle control in the CHOKE posi¬
tion. See figure 7.
NOTE
This unit is equipped with a brake in¬
dicator light which is located on the
dash panel. Whenever the starter key is
on and the brake pedal is depressed, it
will light.
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.
Electric Start
See figures 14 and 15. Turn the ignition key to the
START position. When the engine .s running, let the
key return to the ON position.
FIGURE 14. STARTER SWITCH
FIGURE 15. DASH PANEL LABEL
8

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 re¬
quired to use one tank of gasoline. It
is also recommended to change crank¬
case oil after the first 2 hours of oper¬
ation.
CAUTION
Parking brake MUST be disengaged be¬
fore unit is put into motion.
NOTE
Unit is equipped with separate brake
and clutch pedals. To efficiently stop, it
is necessary to disengage clutch when
applying brakes.
STOPPING THE ENGINE
Turn the ignition key to the left to the OFF position
^ and remove the key to prevent accidental starting.
CAUTION
Gear changing should be done only
after the mower has been brought to a
full stop. 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 in¬
cline.
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 pul¬
ley may cause the engine to stall.
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 disengagement
lever (figure 9) into the DISENGAGED position. 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.
OPERATING THE MOWER
MAINTENANCE
Step 1. Set the desired cutting height.
Step 2. Start the engine as outlined above.
CRANKCASE OIL
To ensure maximum engine performance, perform the
following periodic maintenance:
Step 3. Select gear and shift.
DO NOT force the gear shift lever! If the
lever cannot be moved from NEUTRAL
to one of the drive positons, release the
clutch pedal slowly, depress it again,
and then move the gear shift lever as
required.
Step 4. Once the machine is in motion, remove foot
from the pedal. The mower will now move
ahead or to the rear, and the use of the steer¬
ing wheel will provide directional control.
Step 5. The mower is brought to a stop by pressing
your right foot against the brake pedal and
your IWft foot against the clutch pedal. The
drive belt will be disengaged and the brake
will be applied.
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.
After the first five hours of operating a new engine,
drain the oil (See figure 16.) 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 ensures for minimum wear of engine
parts and provides for virtually trouble-free operation.
To change the oil, proceed as follows:
Step 1. With the machine on level ground, place a
suitable metal container under the oil drain
plug, then remove the drain plug. See figure
14.
9

Step 1. Remove two screws and lift off complete air
cleaner assembly.
Step 2. Remove screen and spacers from foam ele¬
ment.
Step 3. Remove foam element from air cleaner body.
Step 4. a. Wash foam element in kerosene or liquid
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.
FIGURE 16. OIL DRAIN
Step 2. After the oil has been drained completely
from the crankcase, replace the drain plug and
tighten.
Step 3. Refill crankcase with 2Vi pints of good quality,
type MS, Engine oil into the crankcase. Sum¬
mer use SAE 30; Winter (Below 40° F) use SAE
5W-20 or SAE 10W. (Use Wizard 4 Cycle Pow¬
er Mower Oil Stock No. 78-2050).*
LUBRICATION
Lubricate the wheel bearings (2 per wheel) and the FIGURE 18. AIR CLEANER
upper and lower spindle bearings with SAE 30 oil once
a season. See figure 17.
d. Assemble parts, fasten to carburetor with
screw.
FIGURE 17. WHEEL AND SPINDUE BEARINGS
AIR CLEANER
Under normal operating conditions, the air cleaner, lo¬
cated on top of the carburetor, must be serviced after
every ten hours of use. Under extremely dusty oper¬
ating conditions the air cleaner must be serviced after
every hour of operation. Refer to figure 18.
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.
‘Obtain from your nearest Western Auto Store.
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 thjt belts are free of oil or dirt. Wipe the belts
periodically with a clean rag.
NOTE
Belt tension is automatically maintained
by the spring on the variable speed
bracket on the drive belts and the belt
tension on the deck belt is maintained
by the two deck springs.
SPARK PLUG
The spark plug gap should be cleaned and reset to a
0.030-inch clearance every 25 hours of engine oper¬
ation (See figure 19.) Spark plug replacement is rec¬
ommended at the start of each mowing season; check
engine parts list for correct plug type.
10