Fuel Gauge Stuck at Full

[bdericks]

I have a 2003 Maxum 2100 SR and the fuel gauge is stuck showing full regardless of the tank level. I opened up the fuel tank area to look at the fuel sender as I thought this would be my problem. I pulled it out and it looked actually fairly new.

I started inspecting the wires; looks like there is a pink wire and a black. I'm assuming the pink wire goes to the fuel gauge. Not sure what the black one is (assuming power?); it turns into a green and yellow. I'm pretty sure the green one is ground (see pictures). The problem with the green one is that it's not hooked up to anything, so I think that is most likely the problem with the fuel gauge showing full all the time, but wanted to verify that is most likely the problem.

Assuming the ground wire not actually being grounded is my problem, where is a good location to ground it. The wire is really short; I'm sure I'll have to splice a longer section to reach where it should go. Maybe this is why it was never hooked up in the first place. Probably the previous owner said screw it and never did it when they replaced it?

[mmwjr]

The green wire is a bonding wire used to tie all metal objects together so they are at the same potential, ground. Since you have a plastic tank no metal to bond. The black wire is the negative for the fuel sendor and the pink is the fuel sendor sense wire. Yes that looks like a new sendor but I cannot tell if it’s wired correctly.

Try disconnecting the pink wire and see if the gauge moves then ground it and see what it reads.

[bdericks]

Thanks Mike for the reply. I'll test it tomorrow and let you know.

[Gugi47]

When you remove the pink wire, your Gage should go to MT position.

[shrew]

That doesn't look like a solid green bonding wire. That is a Green/Yellow. In Picture #3, those are Home Depot/Lowe's residential-style quick connects. Those are not tinned and are not appropriate for marine use.

Disconnect and reconnect them several times. This may scrape any corrosion that might be impeding conduction. Accor makes marine disconnects.

[bdericks]

Ok so I did what you suggested Mike. When I turn the boat to the "On" position and fuel gauge shows "Full" (always stuck there).

1st and 2nd picture is me disconnecting the pink wire to see if the gauge moves, which is does; moves from "Full" to "Empty".

3rd, 4th, and 5th picture shows me using a lead from my multi meter to connect the pink wire to ground. The gauge stayed at "Empty".

[bdericks]

@Shrew,

These? https://www.westmarine.com/buy/ancor...09_275_004_010

[donald]

Question? How much fuel do you have in your tank?
Don

[bdericks]

@Don,

It's almost full. Previous trip I topped it off before I headed out. Spent the whole day on the lake (a lot of wide open throttle just cruising), and throughout the day I thought it was odd that my fuel gauge never moved. On my way home at the end of the day, I topped it off again (used 28 gallons). My fuel gauge should have been around 1/2 by the end of the day since it's a 50 gallon tank, but as mentioned before, it showed full all day

[bdericks]

So I believe the problem is now fixed. I just pulled the sender again and tested the float vs the fuel gauge. I am now seeing appropriate readings (see pics). I tested it at 1/2 (pic 1&2), 1/4 tank (pic 3&4), and empty (pic 5&6). The only reading that is a bit off is the 1/2. Float is at 1/4, but reading is closer to 3/4 than 1/2. Oh well, it at least I'm getting some readings now.

Thanks to everyone's replies and help. I think I will either change out those connectors or heat shrink them to prevent corrosion or becoming loose again in the future.

[bdericks]

picture #6

[mmwjr]

Yep that was what I would point you to do since the gauge tested fine.

Glad you resolved the issue.

[Gugi47]

Glad to see your problem solve.

[mmwjr]

BTY the problem was not a loose connection as that would have made the gauge read empty just like the first test where you disconnected the wire. I suspect the float was hung up.

[donald]

Glad you got it fixed.
Thanks for posting your findings as it helps others.
Don