Black Or Gray Smoke; Blue Exhaust Smoke - Isuzu C-240PW-28 Technical Manual

ARMY TM 9-2815-254-24
AIR FORCE TO 38G1-94-2
MALFUNCTION
TEST OR INSPECTION
Step 5.
Step 6.
Step 7.

BLACK OR GRAY SMOKE.

Step 1.
Step 2.
Step 3.
Step 4.
12.

BLUE EXHAUST SMOKE.

Step 1.
Step 2.
3-8
Table 3-2. Troubleshooting - Continued
CORRECTIVE ACTION
Defective fuel injection pump.
a.
Remove and test fuel injection pump. Refer to paragraph 3-11.5. If fuel injection pump not
defective, go to step 6.
b. Replace fuel injection pump. Refer to paragraph 3-11.
Check for low engine compression.
a. Perform engine compression check. Refer to paragraph 3-27.7. If compression good, do
step 7.
b. If engine defective, repair or replace engine.
Check for valves improperly adjusted.
Adjust valves. Refer to paragraph 3-26.6.
Check for blocked air intake system.
Remove blockage as found. lf no blockage is found, do step 2.
Check for defective fuel injectors.
a. Test fuel injectors. Refer to paragraph 3-10. If not defective, do step 3.
b. Replace fuel injectors. Refer to paragraph 3-10.
Check for improper fuel injection pump timing.
a. Check fuel injection pump timing. Refer to paragraph 3-13.1. If fuel injection timing is correct,
do step 4.
b. Adjust fuel injection pump timing. Refer to paragraph 3-13.2.
Defective fuel injection pump.
a. Remove and test fuel injection pump. Refer to paragraphs 3-11.5.
b. Repair or replace fuel injection pump. Refer to paragraph 3-11.
Check for blocked air intake system.
Remove blockage as found. lf no blockage is found, do step 2.
Check for defective intake or exhaust valve seals or valve guides.
a. Repair or replace defective components. Refer to paragraph 3-27.4.
b. Disassemble and inspect valve seals and guides. Refer to paragraph 3-27.2. lf not defective,
replace engine.