TM 5-3810-294-34
Table 2-1. Troubleshooting
Malfunction
Probable Cause
Corrective Action
a. Corroded battery cables and/or
a. Clean cables and/or terminals.
1. Engine will not crank.
terminals.
b. Batteries discharged.
b. Refer to TM 5-3810-294-20 and
replace batteries.
c. Faulty starter relay.
c. Refer to TM 5-3810-294-20 and
replace relay.
d. Faulty starter
d. Repair starter (chap. 3).
e. Engine seized due to operation
e. Repair engine as required (chap. 4
without proper lubricant or
and 13).
coolant.
a. Out of fuel.
a. Fill fuel tank.
2. Engine cranks but will not start.
b. Restricted air intake.
b. Refer to TM 5-3810-294-10 and
service air cleaner.
c. Interior of distributor cap is wet.
c. Refer to TM 5-3810-294-10 and
dry interior of distributor cap.
d. Primary ignition circuit open:
d. Refer to TM 5-3810-294-20 and
(1) Loose primary.
(1) Tighten lead.
(2) Ignition points dirt or
(2) Clean or replace points.
burned.
(3) Open ignition switch circuit.
(3) Repair circuit.
e. Primary ignition circuit grounded:
e. Refer to TM 5-3810-294-20 and:
(1) Cracked insulator on
(1) Replace lead.
primary lead.
(2) Ignition points not properly
(2) Adjust points.
adjusted.
(3) Grounded capacitor.
(3) Replace capacitor.
f. Secondary ignition circuit faulty:
f. Refer to TM 5-3810-294-20 and:
(1) Corroded spark plug cable
(1) Clean terminal and/or
terminals. Broken or cracked
replace cable insulation.
cable insulation.
(2) Spark plugs damaged or
(2) Clean or replace plugs.
dirty.
(3) Cracked distributor cap.
(3) Replace cap.
(4) Rotor cracked r rotor
(4) Replace rotor.
contract arm broken.
g. Batteries discharged.
g. Refer to TM 5-3810-294-20 and
replace batteries.
h. Improper valve tappet clearance.
h. Refer to TM 5-3810-294-20 and
adjust valves.
i. Faulty fuel pump.
i. Refer to TM 5-3810-294-20 and
replace fuel pump.
j. Carburetor out of adjustment.
j. Refer to TM 5-3810-294-20 and
adjust carburetor.
k. Extremely low compression
k. Replace piston rings, pistons, or
pressure on one or more cylin-
other engine parts as required
ders.
chap. 4 and 131).
I. Faulty carburetor.
l. Repair carburetor (chap. 3 and
12).
a. Fouled spark plugs. Spark plug
a. Refer to TM 5-3810-294-20 and
3. Engine misfires.
porcelain cracked.
clean or replace.
b. Burned or pitted ignition points.
b. Refer to TM 5-3810-294-20 and
replace points.
c. Incorrect ignition point gap.
c. Refer to TM 5-3810-294-10 and.
adjust points.
a. Restricted air intake.
a. Refer to TM 5-3810(-294-10 and
4. Engine idles rough.
service air cleaner.
b. Low octane fuel.
b. Refer to TM 5-3810-294-10 and
drain -fuel tank. Fill tank with
proper fuel.
c. Carburetor out of adjustment.
c. Refer to TM 5-3810-294-20 and
adjust carburetor.
d. Ignition point gap too narrow or
d. Refer to TM 5-3810-294-20 and
much too wide.
adjust points.
e. Intake manifold leaks.
e. Refer to TM 5-3810-294-20 and.
repair intake manifold.
f. Improper valve tappet clearance.
f. Refer to TM 5-3810-294-20 and
adjust tappets.
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