Generac Power Systems 941-2, 940-2 Section FUEL FILTER AND FUEL PUMP, Fuel Filter, Fuel Pump

Section 3.3

FUEL FILTER AND FUEL PUMP

FUEL FILTER

The fuel filter should be removed and replaced every 100 hours of operation or once each year, whichever occurs first.

Figure 1. Fuel Filter (Typical)

FUEL PUMP

DESCRIPTION:

The 12 volts DC electric fuel pump has a zinc plate finish. Flow through the pump is positively shut off when It is not operating. The pump is actually rated at a voltage of 8 to 16 VDC, but has a nominal voltage rating of 12 VDC.

Current draw of the pump at nominal voltage is approximately 1.4 amperes maximum.

Pressure rating of the pump at zero delivery is 2.0 to 3.5 psi.

Two wires are brought out from the pump. The black wire Is grounded by connecting it to a pump mounting bolt The red wire Is identified as Wire No. 14A. The pump will operate whenever:

•The FUEL PRIME switch on the generator panel is actuated to its "ON" position.

•During engine startup and running conditions when the A6060 circuit board energizes the Wire No. 14 circuit.

TESTING THE PUMP:

1.The pump coil can be tested for an open or shorted condition as follows:

a. Test for "Open":

(1)Disconnect the RED pump wire at its "bul- let" lug.

(2)Set a VOM to its "Rx1 " scale and zero the meter.

(3)Connect one meter test probe to the RED pump wire, the other test probe to terminal end of the pump's BLACK lead. The VOM should Indicate pump coil resistance.

FUEL PUMP NOMINAL COIL RESISTANCE

ABOUT 29.5 kW

b. Test for "Shorted" condition:

(1)Disconnect the RED and the BLACK fuel pump leads.

(2)Set a VOM to its "Rx10,000" or "Rx1 K" scale and zero the meter.

(3)Connect one VOM test lead to the pump RED lead, the other test probe to the pump body. The meter should read "infinity".

2.Pump operation can be tested as follows:

a.Disconnect the fuel line from the outlet side of the fuel pump.

b.Make sure a supply of fuel is available to the Inlet side of the pump.

c.The RED lead from the pump must be connect- ed properly into the circuit The pump's BLACK lead must be connected at the pump mounting bolt.

d.Actuate the Fuel Prime switch on the generator panel. The pump should operate and should pump fuel from the outlet side.

NOTE: If desired, a pressure gauge can be attached to the pump's outlet side. Pump outlet pressure should be 2.0 to 3.5 psi.

Figure 2. Electric Fuel Pump

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