stevo44544

I have a 91 f150, I noticed my battery light was on so I pulled my negative cable while it was running, truck died. So I bought a new alternator and installed it. That fixed that. Went to autozone same day to test starter, battery, and new alternator. Alternator registered 12.7 volts, suppose to be 14v? Starter cranked over with like 300 amps, suppose to be like 100 setting. And my battery was good at about 85%, but it had been dead so that makes sense. So on my way home the water hose rubbed on pully and bursted, and also my alternator went and wasn't charging battery. And ideas???

Just call me Sean

iTrader: (1)

Stop checking alternators like that. You can't pull the cable to check it anymore.

stevo44544

The new alternator kept the truck running with the same test after I put it on. It's an old truck, what method do you use now that's different then then?

Mysterman68

I had a brand new 2000 Toyota that went thru alternators. Found out it was a small leak from the radiator hose right above the alternator. Tightened the hose clamp and never had another problem. Water alone wasn't the problem. The antifreeze was the problem.

stevo44544

That makes sense, my pulley rubbed a hole one upper radiator hose. So I'm assuming it just showered my engine compartment before it was empty and over heated.

Just call me Sean

iTrader: (1)

You use a voltmeter. Unhooking the cable can fry the alternator.

Frances Farmer

This is a question for Sean: I just got a 3g alternator (96 e-150) and noticed the pulley was different. The autoparts woman said it would be fine if I just swapped the pulley from the old one to the new one. Will this affect the performance of the alternator? This must make it spin at a different speed, I'm hoping it won't over or undercharge it. Thanks!

Just call me Sean

iTrader: (1)

Pulley diameter shouldn't matter much. The alternator puts out plenty of juice, the regulator controls how much.

stevo44544

See I was told the same thing. But the diameters looked the same so I didn't play with it. The new alternator is working fine now. I sprayed it down lightly and it worked okay. Now I had another problem with my hoses and the alternator went out for a few mins again but stabilized. Does coolant really effect the alternator that much??

Mysterman68

Yes. It was the cause of my 2000 Toyota alternator failures. See my earlier post.