Section III. REPAIR PROCEDURES

TM 55-4920-373-14&P

8. Check each ignition wire to ensure that they

Ensure that all conditions are satisfactory

are securely connected at the magneto end and

according to the instructions.

the spark plug end.

4-8. ENGINE. Perform the following steps to

9. Check engine mounting bolts to ensure that

determine the condition of the engine.

engine is firmly secured to test stand trailer

frame.

1. Examine engine shrouds to insure that they

are firmly secured.

10. Ensure that there is a sufficient amount of

fuel to run engine.

2. Inspect fan grill for obstructions such as

dirt or foreign objects.

11. Start engine (Chapter 2, Section IV).

Engine should start easily, within 2 or 3 crankshaft

3. Open inspection covers at rear end of cylin-

revolutions.

der head shrouds and look for signs of oil leakage

around valve covers. Replace inspection covers.

12. With engine running, check that normal

4. Check that starting motor, magneto, exhaust

operating speed (2250 RPM Idle) can be attained

with no difficulty.

manifold, oil filter, carburetor, fuel strainer,

and air cleaner are all securely fastened to their

mounting locations.

13. Observe engine exhaust. There should be

no evidence of heavy black smoke or white smoke.

5. Examine carburetor, oil filter, and fuel

Normally the exhaust should emit small amounts

of gray or light black smoke.

strainer for signs of leakage.

14. Listen for unusual noises, such as loud

6. Examine the mating of the starting motor to

the engine front plate for signs of oil leakage.

knocking or sharp metal-against-metal sounds.

7. Remove oil dipstick and check for proper

15. While engine is running recheck all gaskets

oil level.

for signs of leakage. Refer to steps (5.) and (6.).

SECTION III

REPAIR PROCEDURES

CAUTION

Prior to making repairs, disconnect both leads from the battery.

2. Starter Motor. To remove the starter

4-9. REMOVAL AND DISASSEMBLY.

motor (item 12, figure 4-2) proceed as follows:

4-10. Remove and disassemble the components

a. Disconnect cable from starter motor

listed at the direct or general support maintenance

level as required.

terminal.

h. Remove two nuts and lockwashers from

4-11. ELECTRICAL SYSTEM. Remove and dis-

starter support bracket (item 11, figure 4-2).

assemble the electrical system components as

follows:

c. Hold starter motor with hand to relieve

1. Ignition Wire Assembly. To remove the

weight on bolts. Remove three bolts with lock-

ignition wire assembly proceed as follows:

washers holding starter motor into engine.

a. Unscrew one nut from the top of each

d. Pull starter motor out of engine.

spark plug (item 4, figure 4-2).

e. Remove starter support bracket from

b. Unscrew one nut from each of the four

motor removing one screw and plain washer.

terminals located on the magneto (item 1,

f. Replace defective starter motor with a

figure 4-2).

known good motor.

c. Remove one screw and lockwasher

through clip holding ignition wire to engine and

3. Ammeter. To remove the ammeter (item

8, figure 2-1) proceed as follows:

remove ignition wires.

a. Remove two nuts from two studs located

d. Replace defective ignition wire(s) as

on rear of ammeter.

required.

4-20