TM 5-3805-262-34
2-5. FUEL SYSTEM TROUBLESHOOTING (CONT)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
1. FUEL INJECTION PUMP NOT OPERATING PROPERLY (Cont).
Step 4. (Cont).
Slightly rotate test bench drive by hand while observing plunger
lift dial indicator until you get lowest dial indicator reading.
When lowest dial indicator reading is obtained, roller tappet is at
BDC; zero plunger lift dial indicator.
Slowly rotate test bench drive by hand in a counterclockwise direc-
tion as viewed from drive end until plunger lift dial indicator in-
dicates port closure between 0.0847 to 0.0926 inch. Then, set test
bench degree wheel pointer to zero.
Watch plunger lift dial indicator and rotate test bench drive by
hand until dial indicator indicates zero. Number 1 roller tappet
will be at BDC. Remove plunger lift dial indicator and plunger lift
device.
Watch rack travel dial indicator and move control lever until a rack
travel of 0.477 inch is obtained; lock control lever in this posi-
tion.
Turn test bench on but do not drive fuel injection pump. Set test
bench for high pressure phasing.
Watch test line for number 1 cylinder. There should be a steady flow
of fuel from number 1 test line.
Turn off test bench fuel flow.
a. If there is not a steady flow of fuel from test line, turn off
test bench and go to step 5 below.
b. If there is a steady flow of fuel from test line, go to step 6
below.
Step 5.
Turn test bench on but do not drive fuel injection pump. Set test
bench for high pressure phasing.
Watch test line for number 5 cylinder. Rotate test bench drive by
hand. There should be a steady flow of fuel from number 5 test line.
Continue rotating test bench drive by hand. Fuel flow from number 5
cylinder should stop and fuel should flow from number 3 test line.
a. If fuel does not flow from number 5 and 3 test lines, either
fuel inlet port or internal fuel galleries of fuel injection
pump are clogged. Disassemble fuel injection pump (page 3-140)
and clean housing (page 3-148).
b. If fuel flows from number 5 and 3 test lines, remove number 1
delivery valve holder and associated parts (page 3-145). Check
parts for clogged or damaged condition.
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