im stumped

[muddinlate86]

on my 86 my alt was bad.it was the original so it did its job.let me tellm you the situation.when i was at a stop with any acc. on my volt gadge (aft) would drop to 12 volts(only the batt) and when i turned on any thing else it would keep droping till i started to drive agin.so after a hour and a half i got the old one out(located under the smog pump).i drop the nrw one in and its perfect.ten min later hop in my truck and its doing it agin!*** alt good,so what could it be?bad wires or batt term.?any ideas

thanx

 

[Yardape]

That factory gauges are not very good, I wouldnt relay on what you read there. Get a multimeter and test it.

 

[shift1313]

does your alt have the internal regulator? if not ive always been told to change the regulator out with the alt. its the silver box mounted on the fender well next to you starter relay. It could just as easily have been wiring too.

Did you actually put a meter on the battery or check the output of the alt?

 

[muddinlate86]

i checked the new one the old school way by starting it up and taking the batt. cables off.and to yardapes response i have an aftermarket gage "aft" and its pretty acuret.im going to try and get new wires and see if maybe thats the case thanx ill keep you posted.let me know of any thing else you can think of

 

[shift1313]

ive seen the wires pull out/corrode on the back of the connector to the regulator on the firewall. Does your truck have an external regulator?

 

[muddinlate86]

no its internal it has a two plug system.pain in the a$$

 

[92bronco_in_progress]

i know this sounds dumb, but check your posiive and negative battery cables, you might have a bad ground or something of the nature, since the voltometer reads total voltage in the system

 

[muddinlate86]

i did descover today that my ground wire is stripped and nasty where it meets the block i hope thats the problem keep you guys posted

thanx