Fuel guage

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yodagwb
Posts: 117
Joined: Fri Jan 27, 2006 8:34 am

Fuel guage

Post by yodagwb »

Had topped of the tank prior to the winter. Eatly April dropped the boat in and motored 13hrs. Added 5 gal of fuel and motored 17 hrs more. As far as I can tell I should be down 15 to 20 gal or down at least 1/2 a tank. Problem is the guage reads full, full. Turn off the key goes to E turn on the key goes to full. I guess I'll start with replacing the sender unless anyone has a better idea of what happen over the winter. Has anyone had this problem? Has anyome had to replace their sender and in turn know the size or model sender needed? Thoughts?
R.B.
Posts: 233
Joined: Fri Jan 20, 2006 2:04 pm
Location: Ontario, Canada

Re: Fuel guage

Post by R.B. »

I had the same issue last year and ended up replacing the sender unit. Here are the test procedures I used:

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
Ralph

WOLFHELM
C350 #342
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peterhansen100
Posts: 4
Joined: Fri Aug 12, 2011 10:11 pm

Re: Fuel guage

Post by peterhansen100 »

I've had exactly the same problem. I have replaced the sender and I still had exactly the same problem. I have found since that all of the guages are stopping one by one as they've all got salt water moisture in them from waves crashing into cockpit and salt spray. The problem is that there's no seal whatsoever around the instrument panel and salt water and electronics don't mix! I suggest it will probably be the guage rather than the sender as the WEMA sender is very good quality and has no actual moving parts on it. Follow these tests as suggested and replace the guilty part.

Then run a line of foam/double sided tape around your intrument panel to stop the water getting into your guages from now on.

Cheers :D
elk
Posts: 81
Joined: Tue May 01, 2012 12:56 pm

Re: Fuel guage

Post by elk »

i followed the troubleshooting steps above, as I also had a perpetually full tank. The problem was that everything tested good, gauge, wiring, sender, according to the guide. I did a resistance reading on the fuel gauge, and found a higher than expected resistance, not mentioned in the above steps. So I replaced the always full reading gauge with another Teleflex gauge, and it worked, read just over 3/4, which was just about what I expected.

So for you that have followed the steps and haven't found the problem, try the gauge. According to an engineer at Teleflex, all their fuel gauges are correct to use on our systems, so buy the cheap one, I got mine for $26 with free shipping from Overton's.

Good Luck!
Ed Kruzel
S/V Emily
Hull #399, 2006 C350
Cataumet, MA
Flagmanmike
Posts: 25
Joined: Fri Mar 27, 2015 10:42 am

Re: Fuel guage

Post by Flagmanmike »

My fuel gauge was acting intermittently for a while and finally quit. I found an direct form/fit/function replacement on Amazon, Model Sierra 57902P Fuel Gauge Amega 2". It was $23.14 plus tax on Amazon Prime. Installing was easy, and it works great. The only difference I found was the red markings on the dial. All the terminals were identical as well as the light, so no need to fuss with wiring. Hope this helps anyone needing a fuel gauge.
Mike Cronin
FlagShip Hull 314
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