FUEL SYSTEM TESTS, INSPECTIONS, AND ADJUSTMENTS - CONTINUED
AIR IN FUEL TEST - CONTINUED
N OT E
If second sight gage is not available, move sight gage from fuel return line and install sight gage at
inlet to fuel transfer pump.
If excessive air is seen in sight gage in fuel return line, install second sight gage at inlet to fuel transfer pump.
Observe fuel flow during engine cranking. Check for air bubbles in fuel.
If engine starts, check for air in fuel at varying engine speeds.
N OT E
If excessive air is not seen at inet to fuel transfer pump, air is entering system after fuel transfer
If excessive air is seen at inletto fuel transfer pump, air is entering through suction side of fuel
Prime fuel system, if necessary (TM 5-3805-291-10).
WARN I N G
To avoid personal injury, always wear eye and face protection when using pressurized air.
CAU T I ON
To avoid equipment damage, never use more than 5 psi (34 kPa) to pressurize fuel tank.
Pressurize fuel tank with air to 5 psi (35 kPa). Check for leaks in fuel lines between fuel tank and fuel transfer pump.
Replace any leaking or damaged fuel system components.
Check fuel pressure. Refer to Fuel System Pressure Test in this work package.
N OT E
If injector sleeve or injector sleeve O-ring is worn or damaged, combustion gases may leak into the
If source of air is not found, disconnect supply line from fuel tank and connect external fuel supply to inlet of fuel trans-
fer pump. If this corrects problem, replace fuel tank (WP 0033 00).