TM 5-3805-280-24-1
Group 15
Diagnostic Information
DIAGNOSE ENGINE MALFUNCTIONS
NOTE: Diagnostic charts are arranged from most
probable and simplest to verify, to least likely
and more difficult to verify.
Symptom
Problem
Solution
Engine Cranks But Will Not Start
No fuel
Add fuel. Bleed air.
Or Hard To Start
9010
15
Wrong fuel
Use correct fuel.
1
Water in fuel or water frozen in fuel
Drain water from fuel tank trap.
line
Inspect fuel filter for water. Change
filter.
Fuel filter plugged
Replace fuel filter. Bleed air clean
fuel tank strainer.
Debris in fuel
Drain fuel tank. Clean tank strainer.
Add clean fuel.
Air in fuel system
Check for bubbles in fuel filter and
tighten connections. Bleed air.
Fuel pump
Check fuel pump pressure. See
Engine Repair chapter.
Low battery power
Charge or install new batteries.
Slow cranking speed (poor electrical
Clean and tighten battery and starter
connection)
connections. Incorrect engine oil
(Cold weather).
Wrong engine oil
Use correct oil.
Air filter plugged
Check air filter restriction indicator
and air filter elements. Clean or
replace elements.
Standby fuse or relay
Replace fuse, relay or wiring. See
Group 9015-10.
Continued on next page
TX,9010,SB112 1929MAY981/12
3-28
