2-5. FUEL SYSTEM TROUBLESHOOTING (CONT)
TEST OR INSPECTION
3. EXCESSIVE FUEL USAGE (Cont).
Perform engine compression check (page 3-12).
a. If compression check readings are low, put a small amount of oil
in cylinder and repeat engine compression check. If compression
check readings are now normal, replace piston rings (page 4-42).
If compression check readings are still low, compression leakage
is past valves. Refer to page 3-74 to remove and replace valves.
b. If compression check readings are normal, go to step 7 below.
Remove five capscrews securing gear cover and gasket to timing gear
Check fuel injection pump drive gear to idler gear backlash using
Backlash should be 0.012 inch.
a. If backlash exceeds 0.012 inch, replace fuel injection pump
drive gear (page 3-136).
Recheck backlash. If backlash still exceeds 0.012 inch, replace
idler gear (page 4-54).
b. If backlash does not exceed 0.012 inch, reinstall gear cover us-
ing new gasket.
Tighten four 3/8 inch capscrews to 35 to 42 lb-ft. Tighten one
5/16 inch capscrew to 17 to 20 lb-ft.
Adjust fuel injection pump (pages 3-10 and 3-14). If fuel injec-
tion pump cannot be adjusted, go to Malfunction 1, page 2-47.