Farm truck electrical

Mike in Mn. · May 7, 2012

Old 86 Chev pickup, the lights flicker steady, volt meter jumps back and forth. Battery voltage at battery back and forth between 13.5 and 14.1 or so with digital volt meter. Changed regulator in alt. and tried different alt and even changed battery, cleaned all connections and grounds, pulled different fused to try and pin down a particular area, no difference. Any suggestions?? Been like this for a couple months, continues to work, just driving us nuts, Thanks for any info, have a good one!!

oldtanker · May 7, 2012

Have you checked and cleaned the body/frame grounds?

Rick

gregger · May 7, 2012

check the fuse box some get all rusted from the back side -- cannt see it

old · May 7, 2012

Sounds like the good old Chev rust out truck problem and the fact you have to run grounds to places that before the rust where not needed. I have a 1980 Chev truck and I had to run a ground from the battery to the tail lights for them to work and while I was at it I ran grounds right from the battery to the frame of the alternator etc

wisbaker · May 7, 2012

I'd guess a bad ground or a wire shorting somewhere.

toolman · May 7, 2012

Been awhile and my brain doesn,t work as good as it once did, but i would test your Diode Trio, can do it with you meter.

Tech 7 · May 7, 2012

Just a shot...remove and reinstall one fuse at a time noting any changes in voltage....if/when it straightens out with one fuse pulled that is the circuit to focus on. Hope this helps, Bob

LJD · May 7, 2012

Check the big post on the starter solenoid. The main battery cable lug joins the 10 gauge wire that feeds the entire electrical system. When the nut on that stud gets loose gets loose the system does all kinds of weird things. Common problem area since it's hard to get too and often doesn't get tightened properly during a starter motor change.

JDseller · May 7, 2012

I would bet that you have a bad ground cable to the block. You are in MN where salt is used. The cables will go bad inside. Take a good pair of jumper cables an hook directly to the battery to the alternator and see if the problem goes away.

Janicholson · May 7, 2012

If your meter is digital, and changes all the time, it is not unusual. They sample at a given rate, and are difficult to use on vehicles. Use an analog (needle style) meter and it will help isolate the issue. Jim

Anonymous-0 · May 8, 2012

Try a jumper from the negative battery post to the alt body or a real clean/bare place on the motor and see if it does any different....

Farm truck electrical

Mike in Mn.

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oldtanker

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gregger

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old

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wisbaker

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toolman

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Tech 7

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LJD

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JDseller

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Janicholson

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Anonymous-0

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