TM 5-2420-230-24-2
Fuel Flow (005-011)
B3.9 and B5.9 Series Engines
Page 5-16
Section 5 - Fuel System - Group 05
If the fuel is aerated or the volume is low, isolate the fuel
transfer pump by connecting the fuel transfer pump inlet to
a temporary supply, and perform the same check as above.
If the fuel transfer pump delivers the required volume of fuel
from a temporary supply, check for restrictions or suction
leaks in the fuel circuit to the fuel transfer pump:
1. Supply line
2. Prefilter
3. Supply line
4. Supply tank
5. Tank vent.
Check for a plugged supply tank vent first.
In cold weather check for gelled diesel fuel blocking the
prefilter.
Clean or replace the prefilter.
L-876