SHEET 3797651 - Caterpillar

Introduction
The problem that is identified below does not have a known permanent solution. Until a permanent solution is known, use the solution that is identified below.Problem
Failures of the fuel pump such as erratic working, shorted, or open circuit can be due to various causes. The following list is examples of some of the causes that may require some recommended actions.
Dirty foot valve strainer
Damaged strainer
Pump having run dry
Electrical circuitSolution
Note: During any disassembly or assembly, ensure that no debris enters the fuel circuit.This procedure should be used to find out the common causes of failures for the refueling pump.
Illustration 1 g03400175
(1) Foot valve (2) Pump harness terminal (3) Refueling pump
Illustration 2 g03400176
(4) Cover (5) Cover screws and lock washers
Illustration 3 g03400178
(6) O-ring (7) Rotor (8) VanesRecommended Actions
Dirty Foot Valve Strainer
For the 190-5283 Valve As , 229-1860 Valve As , 368-5217 Valve As and the 368-7703 Valve As , the first part to check is the filter. Ensure that the filter is clean and that nothing could decrease the fuel flow. If the filter seems to be damaged or if the fuel flow cannot be guaranteed, the foot valve assembly should be replaced. Where appropriate, ensure that there is no debris inside the fuel circuit.Regarding the foot valves (442-3946, 442-3947, 442-3948, 442-3949), disassemble the cap by removing the circlip. Remove the filter in order to clean the filter. Before reassembly, ensure the entire foot valve is clean.Damaged Filter
A damaged filter could cause irreparable failures to the pump by allowing debris (or some pieces of the filter) to enter the pump. That could jam the pump vanes, deteriorating significantly the pump performances. If any damage is noticed or suspected, the affected parts must be replaced. Ensure that there is no debris inside the fuel circuit.Pump Having Run Dry
The refueling pump may run dry. This could be caused by an empty barrel or the start switch unintentionally pushed.
Remove the three screws (5) of the front cover (4) and remove the cover and check the following:
The O-ring seal (6) cleanliness.
If the rotor (7) can turn by hand.
After having removed the rotor (by axial movement outwards), check the integrity of the vanes (8) .
Replace the appropriate parts using service kits. Reassemble the parts and tighten the 3 screws to 7 0.2 N m (62 1.8 lb in).Electrical Circuit
Note: When testing, never activate the pump without fuel
Illustration 4 g03400101
Illustration 5 g03400170