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1989 Trooper II, fuel gauge issue

450 Views 2 Replies 2 Participants Last post by  Airhead rider
My Trooper II has been sitting in the backyard for the past 7 years with a blown head gasket. I just spent close to $1,000 rebuilding the engine ground up. It runs great with a few exceptions.

1) fuel gauge reads 1/2 to 3/4 all the time
2) cruise control doesn't work
3) left headlight is broken
4) battery tie-down is rusted away

Is there any way to test the fuel gauge to make sure it is ok? If the gauge is alright then it will be time to check the sending unit. I assume this will require removing the tank.

The cruise control has vacuum to it and the cable is in place, I haven't checked further.

Anyone have a driver side headlight or the battery tie-down they are willing to part with?

I am happy to finally get it back on the road. It has 155,000 miles on it. I should be able to get 200,000 more out of it with the new engine (I hope)!

Any information will be greatly appreciated.

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Quick note on the fuel gauge, it's most likely the sending unit and you do not have to drop the tank. If you look at the tank from behind your right rear tire you'll see the sending unit. Real easy to break off some of the retaining screws if rust is involved. I bought my Trooper after it had sat for a long time (blown engine) and the sending unit was rusted in one position.
I'll add if you do pull the sending unit take that opportunity to look in the tank. Mine didn't leak but the entire inside of it was fuzzy rust.
I'll have to look a bit but know I checked the gauge by either grounding a wire at the sending unit connector or applying power to it, right now don't remember but a simple check without disassembling anything. My gauge sat at empty, applying power (I think) made the gauge go to full so that eliminated the gauge as the problem.
I know one wire is low fuel light, one is gauge.
Thinking further, I'm thinking there are two wires coming off the sending unit. Yellow / red is to the fuel gauge, yellow / blue is to the low fuel warning light. Ground the yellow / red with the key on and the gauge should go to full.
I believe this is correct, anyone else? Actually, the fact that your gauge reads anything at all and your vehicles history still makes me think a rusted / frozen sending unit.
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