Fuel & Temp gage

Yesterday while driving my fuel gage pegged on full tank and the temp gage pegged on hot. Not sure what happened. Jeep is 1964 CJ5, Complete rebuild last year with new gage and new wiring harness. Jeep now has 468 miles on it.

Any of you know what could have caused that?

Thanks

Howard

 

1st thing I thought of was bad ground..

 

What gauges do you have? Are you using an external instrument voltage regulator?

 

Inspecting for bad grounds and obvious wiring faults is always a good first step.

Can you read a schematic? Do you own a multimeter and know how to use it?

This thread has a lot of info on factory early CJ-5 gauges: http://www.earlycj5.net/forums/show...instrument-cluster-voltage-regulator-location

Go to the schematic and trace it through.

 

Tim


Thanks for the link. I printed and will trace and test.

Howard E.

Thanks for the info.


Howard

 

Well I am not sure what happened. I removed the gage and took it apart. The only thing I found was the temp gage was stuck on H. I loosened it and it fell back to C. I have cleaned up some ground areas and temporarily wired it to check out before installing. All seemed to work well.

 

both gauges ground to the back of the speedo housing. it is fairly common for corrosion to foul this connection. i added a ground wire from the fuel gauge to the housing to combat this issue

 

Actually the temp gauge does not ground to the speedo housing. The temp gauge ground is through the temp sender at the engine.
Your idea of adding a ground to the fuel gauge to the speedo housing is something that the gauge manufacture should have done in the beginning. The fiber board on the fuel gauge will warp over the years and cause the gauge to loose ground.

 

i took advantage of this warp to pass the ground wire through...and i thought the temp worked that way(ground to sender) i added a ground to it as well though, no issues it works

 

When I reinstalled the gage I added a ground wire from the battery to the firewall and cleaned up the area around the firewall connection to the gage.

Another question.

When I tested the oil light it worked OK but shouldn't it come on when the key is on and the engine is not running? All the connections are good.

 

when cleanning up the ground aera under the dash, Do you use a coating to prevent an corrosion?

 

The same thing "kinda" happened to me but I'm not sure of the water meter because I have an aftermarket unit...my fuel gauge however had always read lower than it actually was until I filled it completely one day...it now reads full until I get down to about three gallons & that's about when it dips below the full mark. I pulled it out last week to look at it & it didn't feel right & the float was about half full of fuel so I ordered a new one that should be here today. If it doesn't solve the problem I'll try grounding it.


ETA:...I just got the sender in & thankfully that solved MY problem...it's good to have a working fuel gauge again...