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4/07/2017 3:39 PM  #1


68brake light works now gas guage

Ordered new brake light Switch   When crawled under dash found switch was unplugged   

Now gas guage only goes to half full when tank is full. Guage goes to E when key turned off. 

Guess is sending unit. Any suggestions on how to test sending unit?

Car was in storage for two or three years. Could be four years

Any suggestions on testing and replacing sending unit is appreciated

Thanks,

John

 

4/07/2017 4:57 PM  #2


Re: 68brake light works now gas guage

Crawl under the car and disconnect the lead to the sender then ground it (the lead) to the chassis or tank.  Turn ignition to ON and see what the gauge does.  It should go to full and if it does that's an indication that the sender is bad or seriously out of adjustment...which is not unusual if it has been replaced with a RePop unit.  If the gauge seems good (it goes to full in this test) then you will need to pull the sender and to calibrate it or replace it.  Either way you'll need to calibrate.  If you wish, PM me with your email addy and I'll send you a write-up and templates that I came up with to cal the sender. 

BE SURE TO DRAIN THE TANK DOWN TO THE LAST COUPLE OF GALLONS BEFORE PULLING THE SENDER.  AND DON'T MAKE SPARKS!!!!

BB


"you get what you pay for, good work isn't cheap, and there are NO free lunches...PERIOD!"
 

4/08/2017 5:52 PM  #3


Re: 68brake light works now gas guage

Note:  Only ground the gauge sender wire momentarily, just long enough to see if the gauge is going to peg out..  Not sure if it will, but I have always thought it might damage the gauge if allowed to stay pegged from a fully grounded condition.  The sender "grounds" the gauge at a variable rate of between 10 and 75 ohms. 

You probably have a float that has gas in it, and it won't rise to the occasion of a full tank.  I have an extra brass float you can have if that is your issue.


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
 

Board footera


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