TM 5-2420-230-24-2
roubleshooting Symptoms Charts
B3.9 and B5.9 Series Engines
Page TS-56
Section TS - Troubleshooting Symptoms
Engine Will Not Crank or Cranks Slowly
This is symptom tree T076.
Cause
Correction
Use a starting aid and the correct oil grade.
Refer to the Operation and Maintenance
Engine speed is low because of cold ambient
.......
Manual, B Series Engines, Bulletin No.
temperature
3810205, for oil specifications.
OK
B
Check battery. If the battery is low check the
alternator for proper charging. Charge the
attery charge is low
.......
battery, and replace if necessary. Refer to
Procedure 013-001 or the OEM service
manual.
OK
E
Check the engine cranking speed with a
handheld tachometer or electronic service tool.
If the cranking speed is slower than 150 rpm,
ngine cranking speed is too slow
.......
refer to the Engine Will Not Crank or Cranks
Slowly symptom tree.
OK
C
Check the voltage drop in the starting circuit.
ranking circuit or battery cable voltage drop
.......
Refer to Procedure 013-009. Repair or replace
excessive
cables if necessary.
OK
P
Check for proper ground between starting
oor starter motor ground
.......
motor and battery negative terminal. Repair or
replace if necessary.
OK
C
Inspect the battery cables for loose or cor-
roded connections, or broken cables. Check
ranking circuit or battery cable voltage drop
the voltage drop in the starting circuit. Repair
.......
excessive
or replace the battery cables if necessary.
Refer to Procedure 013-009.
OK
S
Check the voltage drop in the starting circuit.
Refer to Procedure 013-009 or Procedure
tarter relay voltage drop excessive
.......
013-017. Repair or replace starter relay if
necessary.
OK
T
(Continued)
L-640
