Fuel Gauge Test Procedure
Seaward Products
July 5, 1994
SPECIFIC TEST PROCEDURE FOR FUEL GAUGE USED BY CATALINA YACHTS
(Other systems may use a different procedure)
There are FOUR components in the fuel gauge system on Catalina Yachts and therefore four possible sources of fuel gauge problems.
1 - The fuel GAUGE in the engine control panel may be defective.
TEST PROCEDURE :. . . . . Disconnect PINK sender wire from "S" terminal on gauge. Turn on ignition switch. Pointer must deflect to extreme left. By temporarily shorting out the "S" (sender" and the "G" (ground) studs, pointer must deflect to the extreme right. Re-connect the PINK sender wire to the gauge, after the test.
2 - The pink SENDER WIRE may be DISCONNECTED from the sending unit at the tank, or SHORTED TO GROUND.
TEST PROCEDURE : . . . . . Disconnect pink SENDER wire from terminal on sending unit in tank. Attach pink wire to a KNOWN GROUND, such as engine block or battery NEGATIVE. DO NOT ASSUME THAT FUEL TANK IS GROUNDED. Turn on ignition switch. Pointer must deflect to extreme right, as in previous test. Disconnect pink wire from ground. If pointer STILL deflects to extreme right, pink wire is GROUNDED at some point between sender and gauge.
Check all connection points on pink wire, or replace entire wire.
3 - The black GROUND WIRE may be DISCONNECTED from the sending unit at the tank, or NOT GROUNDED at the other end.
TEST PROCEDURE : . . . . . If the gauge tests "GOOD", and PINK wire tests "GOOD", attach pink wire to the black GROUND wire on the sending unit in the tank. If pointer does not deflect to right, (as in test above),, the black wire IS NOT GROUNDED.
Follow the black wire from the sending unit in the tank, and make sure it eventually CONNECTS TO GROUND.
4 - The SENDING UNIT in the tank may be defective, or the wrong unit may have been installed.
TEST PROCEDURE : . . . . . If the gauge tests "GOOD", the PINK wire tests "GOOD", and the black GROUND wire tests "GOOD" the sending unit in the tank is defective, or the "WRONG" unit may have been installed. The "CORRECT" sending unit has a specification of:
STEWART WARNER GAUGE, 33 to 240 OHMS RESISTANCE
There are several other resistance specifications available, but those sending units WILL NOT WORK in this application. In the past the sender and gauge have been orderable from Catalina Parts. If Catalina cannot supply the parts order direct from Seaward Products, 3721 Capitol Avenue, Whittier, CA 90601-1732. Phone: (502) 699-7997; Fax: (502) 699-0908