Alternator Problems?

kikenhorse · Feb 19, 2004

The battery in my 86 B2 does dead and needs to be charged. I switched batteries --same prob.
If I disconnect a battery cable and the engine dies does this mean the alt, is not putting out?
I suppose it could be a short draining the battery overnight..
HELP

kikenhorse · Feb 19, 2004

Thats "goes dead" and it is real cold here way below freezing.

Txquadhunter · Feb 19, 2004

the alt. is a good place to start. if you it goes dead when you pull the battery cable off while it's running. unless you've got alot of power being pulled at the same time IE head lights on and such. also have some one hold it at a higher RPM while you unhook battery. If you've done any work under the hood before this happend check one of the single wires that runs from the alt. to the silanod(spell check) it can easily be knocked loose. Since been so long since i owned my ranger i forgot the wire color. regulator can also cause the same problems. but your truck should stay running when you unhook a battery cable. Yes shorts can drain the battery over night. Tracing them can be a PITA. When i used to work in a shop rebuilding alt's and starters we had a few come in where a bad alt was causing a short that drains the battery. If you have a volt meter you could test the current output but i can't remember all the volts that it should be putting out. a good shop manual like chilton's can step you thru.

davids78bronco · Feb 20, 2004

Txquadhunter said:
If you have a volt meter you could test the current output but i can't remember all the volts that it should be putting out. a good shop manual like chilton's can step you thru.

hehe, you can't test the current, while trying to read the voltage, on the same meter

We know what you meant tho.

The alternator should be putting out between 13.4 and 14.4V. With the engine running, ground the tester (battery Negative, body, frame... just a ground), and touch the Positive lead to the Pos terminal on the back of the aternator

If the alternator and regulator tested fine, there's some test you do with the voltmeter, and pulling each fuse in the fuse panel - f*ck if I remember tho, it's 2am... I'm going to bed

kikenhorse · Feb 21, 2004

Thanks for the advise !!! I will give the thing a test or 2 tomorrow. Supposed to be warmer here.
Really should take the damn thing off & get it tested... before it leaves me in a mess on the side of the road.

kikenhorse · Feb 25, 2004

:mellow: Thanks for the help. The alt. did not test well at all. The rebuilder charged 60 bucks. Thats off . I can live with that.

(

fbrown3 · Jul 13, 2004

There is a way to make a cheap tester!!! to test for current draw in the electrical system. (1) get an old door buzzer from an older vehicle and attach two wires to the leads. (2) with the engine OFF disconnect the (pos)(+) post and connect the tester in series between the battery terminal and the battery post if it buzzes you have a current draw. remove one fuse at a time to find where the current draw is(if still buzzes replace fuse).(remember if you have a clock in your radio it will make it buzz slightly)and if the current draw is in the dome light circute you may have to pull more than one fuse to make the buzz stop. If you pull all the fuses and it still buzzes then disconnect the starter wire and then alt. I have seen both cause a draw on the battery, but work fine. (I use an old Chevy door buzzer) and it has kept me from chasing my tail on many current draw problems. Hope this will help some one in the future. (I found this in an old Popular mechanics magazine)