ARMY TM 9-6115-641-24
AIR FORCE TO 35C2-3-456-12
Table 2-6. UNIT TROUBLESHOOTING - Continued.
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Step 4. Check blocked exhaust pipe or muffler.
a. If blocked, unblock or replace muffler, paragraph 2–65.
b. If exhaust pipe and muffler are not blocked, notify next higher level of maintenance.
7.
ENGINE KNOCKS.
Check for contaminated or incorrect grade of fuel.
a. If contaminated or incorrect grade, drain fuel tank. Replace fuel filter/water separator element, para-
graph 2–87, Service fuel tank with clean fuel of a proper grade (Table 2–2). Prime engine fuel sys-
tem in accordance with TM 9–281 5–252–24.
b. If fuel is not contaminated and correct grade, notify next higher level of maintenance.
8. BLACK OR GREY SMOKE IN EXHAUST.
Check for improper grade of fuel.
a. If improper grade of fuel, drain fuel tank. Service fuel tank with clean fuel of a proper grade
(Table 2-2). Prime engine fuel system in accordance with TM 9-2815-252-24.
b. If proper grade of fuel, notify next higher level of maintenance.
9. BLUE OR WHITE EXHAUSTS SMOKE.
Step 1. Check for improper grade of fuel.
a. If proper grade of fuel, do Step 2.
b. If improper grade, drain fuel tank. Service fuel tank with clean fuel of a proper grade (Table 2-2).
Prime engine fuel system in accordance with TM 9–2815–252–24.
Step 2. Check for defective thermostat, refer to TM 9-2815–252-24
a. If defective, replace thermostat in accordance with TM 9–2815–252–24.
b. If thermostat is not defective, and trouble persists, notify next higher level of maintenance.
10. HIGH OIL CONSUMPTION.
Step 1. Check for blocked air intake system.
a. If air intake system is not blocked, do Step 2.
b. If blocked, unblock or replace air intake system components as required, paragraph 2-66.
Step 2. Check for improper lubrication oil.
a. If improper, drain crankcase and refill with proper lubrication oil (Table 2–3). Replace oil filter in ac-
cordance with TM 9–2815–252–24.
b. If proper lubrication oil and trouble persists, notify next higher level of maintenance.
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