Sticking gas gauge remedy?

[Uwe Blab]

I have a stock, behind-the-seat gas tank. I'm having problems with the gas gauge sticking, usually registering full or near full. I've tried rocking the truck to break the float loose in the tank but that typically doesn't work. Filling the tank with gas won't dislodge it either. Any thoughts on something I could do to keep the float from sticking in the first place? My ideal is to mount an under bed tank, but that's a discussion for another post.

Thanks for any help.

Regards,
Adam

[special-K]

It could be the wire for the gauge is grounded out.When that happens the guage goes to full.If it`s a hung up loat,take out the seat,then tank,and pull the assembly from the tank to inspect and go from there.

[Uwe Blab]

I'm guessing it's a stuck float because sometimes it will unstick itself if I hit a bump or turn a corner and register accurately.

How big of a project is it to pull the tank? I've removed the seat before so that's not a big deal.

Is it a fairly common thing to have the float stick with these types of tanks?

[68gmsee]

As special-K mentioned, first check your wiring and make sure the gauge itself is working properly. Do a search on fuel gauge to see if you find some pointers there. There's been several posts on this site and articles on the net on how to check it to see if it's working properly.

If you haven't seen one before, the sending unit is basically a rheostat. A bunch of windings and the float contact extension moves on these windings. I've been able to clean them before but if they're badly worn or corroded then you just have to purchase a new one.

I've replaced the sending unit without removing the tank before, but you have to use extreme caution. No static electricity, use non ferrous drift punch to remove the unit, make sure battery is disconnected, etc.

If you decide to remove the tank: Remove all fuel from the tank, take the seat out, all the bolts and basically just remove the tank from there. I usually lube the grommet with petroleum jelly or similar and remove it first.

[Uwe Blab]

Thanks for the help. Sounds a little hairy...potentially. Guess I shouldn't be smoking a cigar while I do this?

[68gmsee]

Originally Posted by Uwe Blab

Thanks for the help. Sounds a little hairy...potentially. Guess I shouldn't be smoking a cigar while I do this?

Definitely no

It's really not that hard. I have a brass drift punch that I use to tap around the retainer ring a little a time until it clears the small humps.

If you suspect that it's bad -if it's the original there's a strong possibility -I'd order a new one before removing it. This way you won't have to do the work twice.

[theyammieguy]

I just replaced the oring and retainer ring last weekend. Nothing to really be worried about. You can remove the ring with a pair of channel locks but putting it back on will take a punch and hammer.

[Uwe Blab]

The sending unit is a new one. My Dad was nice enough to replace it not long after I bought the truck (a couple years ago), but unfortunately I didn't get to be part of the "festivities". So I'm pretty sure it's just the float that's sticking. I figured based on the shape of the tank it gives the float opportunity to hang up at the top. If the gauge registers correctly and the tank gets to half full or below it will continue to read properly. Then when I fill up again I run about a 50/50 chance of the float hanging up at some time during the top quarter of the tank.

Bottom line, it seems I need to pull the unit out of the tank and see if anything is obviously awry.

[69gumby]

Tap on it, that what most airplane pilots do.

[captainwillie]

Tap on it? No real pilots just right it up and let MX figure it out. But, yeah, if it was my truck, I'd probably have to do the tappin myself.....Captain Willie

[big blue 72]

most of the time with these trucks its the float that has a hole in it or has just deteriorated from being 40+ years old.
Take it apart, its not that hard .

[68gmsee]

Originally Posted by Uwe Blab

The sending unit is a new one....

My memory seems a little less hazy now... It was about 10 years ago and mine was a new one that came in defective. It would bind inside the tank. I wound up reordering from a different vendor cause I screwed up the first one trying to get it to work.