PLUG 9G7516 - Caterpillar

Engine:
C13 (S/N: LEE1-UP; S3C1-UP)
C15 (S/N: SDP1-UP; B5R1-UP)
Truck Engine News SEBD6808, 1 January 2008, "Procedure for the Lift Test on the Fuel Transfer Pump". Disregard the original article. Refer to the information below.Multiple transfer pumps on the C13 and the C15 have been replaced because of a wrong diagnosis of the Low Pressure Fuel System (LPFS). If the diagnosis is to replace the fuel transfer pump first perform a lift test on the fuel transfer pump in order to make sure that the fuel transfer pump is the real issue.Follow the steps below in order to perform the lift test on the fuel transfer pump.
Disable the engine's electronics so the engine will not start. Disable the engine's electronics by disconnecting the engine's primary speed timing sensor and the secondary speed timing sensor.
Open the purge valve on the secondary filter base. Turn the purge valve three times. The purge valve must be opened in order to allow a bleed path or the test will not work correctly. Remove the inlet from the fuel transfer pump and install a clear hose. Insert the clear hose into a bucket of clean diesel fuel.
Crank the engine.The fuel pump should lift the fuel to the transfer pump within 15 seconds.If the fuel pump does not lift the fuel to the transfer pump, the fuel transfer pump is considered to have failed for a LPFS.Note: The minimum distance for the fuel transfer pump to lift the fuel is 686 mm (27 inch).If the system is introduced to excessive air then the gear-driven fuel transfer pump will have priming difficulty. This happens because the transfer pump can not displace the air without an open purge path.Air that may enter on the suction side can reduce the priming of the fuel against a solid fluid head. This may cause the engine not to start or this may cause the engine to start hard. A purge path at the secondary filter base must be created in order to purge the air from the system. A purge path will also allow the fuel transfer pump to prime.Check for air that may enter the system at the primary filter base.Refer to Troubleshooting, RENR9343, "C13 and C15 On-highway Engines " if the fuel transfer pump performs correctly during the lift test.