Still having fuel gauge issues...I think?

[pbolden]

Hello Everyone,

The fuel gauge was jumping erratically from full to empty to half full and so on. I cleaned the battery terminals and the gauge settled in at a little more than a quarter tank with no more erratic jumping so I thought that the issue was resolved.

About a week later I put $150 in fuel in. When I started the engine the needle pinned to full. While underway occasionally the needle would sharply jump from full to empty and back again but always to the full position. Also, $150 in fuel add to the existing fuel should not have been enough to completely fill the tank but it would have been very close.

If it were a ground issue wouldn't the other gauges be effected as I think they're sharing a common ground? Any further thoughts?

Thanks,
Paul Bolden

 

[Bondo]

Re: Still having fuel gauge issues...I think?

Hello Everyone,

The fuel gauge was jumping erratically from full to empty to half full and so on. I cleaned the battery terminals and the gauge settled in at a little more than a quarter tank with no more erratic jumping so I thought that the issue was resolved.

About a week later I put $150 in fuel in. When I started the engine the needle pinned to full. While underway occasionally the needle would sharply jump from full to empty and back again but always to the full position. Also, $150 in fuel add to the existing fuel should not have been enough to completely fill the tank but it would have been very close.

If it were a ground issue wouldn't the other gauges be effected as I think they're sharing a common ground? Any further thoughts?

Thanks,
Paul Bolden

Ayuh,... The tank gauge Sender, grounds through it's own ground, At the Tank,...

 

[pbolden]

Re: Still having fuel gauge issues...I think?

Thanks Bond-o,

I'm just learning a lot of this. I did pull some diagrams and see the ground that goes from the sender back t.o the battery.

Thanks
Paul Bolden

 

[eligonzalez2010]

Re: Still having fuel gauge issues...I think?

Thanks Bond-o,

I'm just learning a lot of this. I did pull some diagrams and see the ground that goes from the sender back t.o the battery.

Thanks
Paul Bolden

It's been a while since I've done this hand on but here goes some advice. Please folks correct me if I get a few things backwards.

Test your fuel gauge first. Disconnect the S terminal and the gauge should read empty. Ground the S terminal and your gauge should pin to full. (I may have these two results backwards. Can't remember) If both of these tests provide the correct result then move on to the next step. If not then replace the gauge. See Note at bottom.

Reconnect your G (ground) and S(send) wires to the gauge. Get access to the fuel sending unit on the top of your fuel tank. There should be two wires going to the sending unit which connect to the gauge itself. Disconnect the two wires here and clean both the terminals and the wire ring connectors. If you touch these two wires together then your fuel gauge should pin to full. If it does then we know your fuel gauge works. See Note at bottom.

If not then check for continuity on each wire with an ohm meter.
To check for continuity touch one end of ohm meter to one terminal on the back of the gauge and then the other end to the corresponding wire at the fuel sending unit while these wires are disconnected. You should get a 0ohms reading if the wire is good. If you get a blank screen or high reading then the wire probably needs to be replaced. If both wires get a good continuity reading then replace the gauge.

Next, after you have cleaned these two connection, reconnect the wires to the fuel sending unit and then check to see if the fuel sending unit reads correctly. If it does not then you probably have to replace the sending unit. It should be about 5 - 8 screws and you can slide it out of the tank and put a new one in.

NOTE ***My boat requires that I turn the key in order for the fuel gauge to provide a reading. I'm sure you probably have to also. ***

Hope this helps. Let me know what you find.