TM 9-2815-225-34&P
2-7. TROUBLESHOOTING SYMPTOM INDEX
TROUBLESHOOTING
MALFUNCTION
MALFUNCTION
PROCEDURE
NO.
PAGE
1.
Engine will not crank ..........................................................................................
2-3
2.
Engine cranks but fails to start ...........................................................................
2-3
3.
Engine starting motor operates but does not engage ring gear ............................
2-4
4.
Engine stops .....................................................................................................
2-4
5.
Engine fails to stop ............................................................................................
2-4
6.
Engine overheats ...............................................................................................
2-4
7.
Excessive exhaust smoke ..................................................................................
2-4
8.
Low oil pressure ................................................................................................
2-5
9.
Engine knocks ...................................................................................................
2-5
10.
Excessive fuel consumption ...............................................................................
2-5
11.
Excessive oil consumption .................................................................................
2-5
12.
Excessive engine vibration .................................................................................
2-7
13.
Engine will not idle .............................................................................................
2-7
14.
Fuel leaks at pump or injector ............................................................................
2-8
15.
Engine does not develop full power ....................................................................
2-8
16.
Engine misses or runs erratically ........................................................................
2-8
17.
Excessive gear noise .........................................................................................
2-9
18.
Excessive oil loss ..............................................................................................
2-9
19.
Sludge formation in crankcase ...........................................................................
2-9
20.
Lubricating oil diluted .........................................................................................
2-9
21.
Low compression ...............................................................................................
2-10
22.
Engine overspeed ..............................................................................................
2-10
NOTE
For further engine troubleshooting information, refer to the Cummins Troubleshooting and
Repair Manual, NT 855 Engine, Bulletin No. 3810298-00.
2-8. MECHANICAL TROUBLESHOOTING
Table 2-1. Mechanical Troubleshooting.
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
1.
ENGINE WILL NOT CRANK
Step 1.
Remove rocker covers, and rotate engine by attaching a socket and breaker bar to accessory drive nut. Check for
bent pushrod(s), and valve(s) not opening or closing.
If valve(s) fail to open or close, manually open valve with 3/4-in. wrench. If valve(s) are seized, remove
corresponding cylinder head (para. 3-24).
Step 2.
Test for mechanical or hydraulic seizure. Remove the fuel injectors (para. 3-23). Turn the engine over several times
to displace the liquid from cylinders through the injector openings.
If engine can be turned freely after all liquids have been displaced, install the injectors. If the engine cannot be turned
over freely by hand, disassemble the engine and replace the defective parts.
2.
ENGINE CRANKS BUT FAILS TO START
Step 1.
Test for broken fuel supply pump driveshaft.
Replace the injectors (paras. 3-23 and 3-82).
2-3
|
|
