Fuel Supply System Check - Continued
8. Use 3/8 inch quick connect double male to install fuel pressure tester between line (Figure 4, Item 2) and inlet
of fuel lift pump (Figure 4, Item 1). Start engine (TM 5-3805-292-10) and check for the following:
a. Vacuum between inlet of fuel pump and tank exceeding 2 inHg (50.8 mmHg) under full load. If vacuum
reading exceeds 2 inHg (50.8 mmHg):
(2) Check lines and connections from fuel filter inlet back to fuel tank for damaged lines (kinks create
restriction; rub marks may allow air to enter) and leakage at O-ring fittings (WP 0017).
(4) Check fuel tank cap. Be sure a vacuum is not being formed in fuel tank. A vacuum at tank would
reduce fuel supply pressure to injection fuel pump inlet. Vacuum in fuel tank might not be observable
during short-term running.
b. If vacuum is less than 2 inHg (50.8 mmHg), replace fuel filter (WP 0041).
9. Shut off engine (TM 5-3805-292-10), remove fuel pressure tester, and connect lines.
Figure 4. Fuel Pump Supply.
END OF TASK