TM 10-3950-206-12
Section VI. TROUBLESHOOTING
recommended is described opposite the probable
4-15. Troubleshooting
cause. Any trouble beyond the scope of organizational
This section provides information useful in diagnosing
maintenance as reflected in the maintenance allocation
and correcting unsatisfactory operation or failure of the
chart shall be reported to direct support maintenance.
Pettibone Model 10FM Warehouse Crane and its
Refer to table 4-2.
components. Each malfunction stated is followed by a
list of probable causes.
The corrective action
Table 4-2. Troubleshooting Chart
Malfunction
Probable cause
Corrective action
1. Engine will not crank
Dead battery or loose leads to
Check battery to ground lead, battery
starting motor.
to starter lead and then, once
satisfied there is continuity test
batteries (para 4-27).
2. Engine cranks but will not
a. Weak battery.
a. Charge or replace with serviceable
start.
battery (para 3-10).
b. Faulty ignition or fuel system.
b. Turn on ignition switch and dis-
connect one spark plug lead
and hold it about 3/16 from
engine block. Crank engine to
see whether spark occurs. If
spark is present, fault is probably
in fuel system. If spark is
absent, check ignition coil, dis-
tributor, and points (para 4-24,
c. Defective distributor.
c. Remove cap from distributor. Con-
nect short piece of high tension
wire to terminal of coil. Turn on
ignition switch and hold lead
about 3/16 inch from engine
block. Crank engine. If no
spark occurs, inspect and replace
distributor or coil as necessary
d. No fuel in tank.
d. Fill fuel tank (para 4-48).
e. Fuel not reaching the
e. Open carburetor shutoff cock at
carburetor. fuel tank. If this does not help,
check for restrictions in fuel
lines and fuel pump; remove
restrictions (para 4-48).
f. Carburetor flooded.
f. Turn ignition switch to ON posi
tion, and press accelerator pedal
to floor plate, attempt to start
engine (para 2-9).
g. Air leak in intake manifold.
g. Place a small quantity of oil
around suspected leak. A leak
is indicated when oil is drawn
to interior of manifold. If
possible, repair manifold and
install new gasket (para 4-54).
h. Spark plug gap improperly set
h. Using a spark plug gage, set gap
0.025 (para 4-24).
3. Engine does not develop
a. Air cleaner dogged.
a. Clean air cleaner (para 4-41).
full power.
b. Low compression.
b. Perform compression test (para
c. Fuel lines clogged.
c. Clean fuel lines (para 4-46 & 4-48)
d. Intake manifold leaking.
d. Tighten manifold nuts or install
new gaskets (para 4-54.)
e. Improper ignition timing.
e. Correct ignition timing (para 4-50).
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