Generac Power Systems 941-2 - Manual (Page 61)

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.
Figure 2. Electric Fuel Pump
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 k W W
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.
Page 3.3-1