Fuel gauge stuck on full?

[2dogsbarkin]

About 3000 miles ago the fuel gauge stuck on full and has been stuck there ever since.
Anyone have this happen?
also my guess is that the gen. and hydra hot pick up fuel from a higher point as not to run me out of fuel. We boondock a lot.
Heading out now to look over the top of the tank connections and make sure no critters are nesting on it.

[Smitty77]

Now that is one fine looking rig! (High Cascade?, Newport? Other?)

Just think of the money you'll save, always being full...

Somewhere around the 1/4 full mark, is the tribal knowledge that I've picked up on the cutoff draw down points for the generator and HydroHot.

Good luck on finding the cause of the stuck gauge, I'll follow the post to see what it ends up being.

Best,
Smitty

[John Jones]

Mine stays on full for 1/2 of my tank then it starts to drop. I will be following this thread to see what you come up with.

[gbburgess]

Mine never gets to full - only about 3/4. It's been that way for about 25,000 miles. I never believe it anyway. I always use miles driven times my known MPG.

[waternut]

Check the connection on the fuel sending unit and make sure it has a good ground. The sending unit could be bad and no longer changing resistance as the float goes down, only fix for that would be to install new sending unit. You can pull it can read it with an OHM meter and confirm that the unit is the problem and not a wiring issue, should change resistance as you move the float up and down.

[pumper9x9]

ya what waternut said. However if that all checks out your problem is probably in your tank. Been there done that paid the bill. However it you're going to pull the sending unit have a replacement ready to stick back in it will save you a lot of time, labor, knuckles, and peace of mind. You can always take the sending unit back if you don't need it.

[TQ60]

Check power on back of gage.

[BRex45]

TQ60 said: Check power on back of gage.

That is a great first step. Also consider lightly smacking the gauge or top of the dash.

If there is power at the gauge I would check the grounding wire at the sender unit on the tank. Try grounding the ground wire to a good chassis ground to "make sure" it is good.
Also try grounding the center post on the sending unit. Grounding the center post will make the dash gauge read "full" if there is continuity between the sending unit and the dash.

I have seen the gauge floats hang up (rarely) and sometimes the rheostat portion of the sender wears out.

Hope this helps. Good luck getting to the sending unit location.

[2dogsbarkin]

Here are the before and after pictures of the fuel tank sensor:




I cleaned it with a can of Brake Clean and an old toothbrush. At this point the tank was full. I moved the full rheostat back and forth until I got the needle of the gauge to hover around the full tank mark.

We left on a 200 mile trip and the gauge stayed at full most of the way. Then, suddenly, dropped to a 1/4 tank and hovered around there for the rest of the trip. When we got to the campground I got back in and adjust the full rheostat to bring it up to the 5/8 full mark, which is where I am guessing the gauge should be based on fuel usage.

In 3 days we are going to be traveling about 300 miles. I will report back.