TRUCK SERVICE MANUAL
Open shut-down value on top of fuel pump.
Check 9: Shut-down Valve not open.
Replace gear pump if it will not deliver required flow.
Check 10: Gear pump worn.
Mesh fuel pump and test stand drive couplings.
Check 11: Drive coupling not in mesh.
Correction
Cause
Remove fuel pump from test stand then remove front cover
Check 1: Front Seal leakage. This can be determined by
and install new seals in cover.
covering "weep hole" in front cover with Lubriplate which stops
air entertainment.
Tighten suction connection or replace if mutilated.
Check 2: Suction connection not tight or is damaged. This
can be determined by pouring lube oil over suction
connection.
Replace gaskets as required.
Check 3: Main housing or spring pack housing gasket
leaking air.
Remove fuel pump from test stand and disassemble pump
Check 4: Tachometer drive seals leaking. Check by pouring
enough to replace tachometer drive oil seal in main housing.
Fill fuel reservoir with Cummins test oil.
Check 5: Fuel level in test stand reservoir low.
Replace "O" ring on throttle shaft or replace housing if
leaking.
Check 6: Throttle shaft "O" rings or housing leakage can be
determined by pouring fuel oil over housing.
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