Need help-Charging too low!!!

[prayers1 153]

I had a Promaster one wire 140/80 Amp Alternater. It was charging around 14 volts before I droped it off at the Bodyshop about a 1 1/2 years ago.

 

Recently I got the car back and I drove it for the first time today, approx. 20 min. Lucky for me, my last stop was at my friends Machine Shop where it died. The battery was dead and a voltmeter confirmed that the Alt. was not charging above 11V. We bench tested the alt and the needle was erratic and would it would surge

 

He said that it would cost me more to rebuild my alt. than to buy a new one. So, he gave a new GM one wire 75 amp alt. We also bench tested the new to make sure it was OK and it was.

 

At home, I installed the new Alt, and previously had the battery fully charged. The battery reads 12.80 before starting. After starting the car, the battery reads 12.67 . With the lights on or a high rev it stays the same. I have a ground from the battery to the frame, ground from the alt. to the motor and a ground from the motor to the firewall. I have new Battery and Starter cables, a new solenoid, heavy gauge wire with a fuse going from the alt post to the solenoid and the belt is tight.

 

I also unpluged the main wire feed to the dash panel and it still reads the same.

 

So, why is it not charging???

.

Edited September 27, 2013 by prayers1

[prayers1 153]

It won't harm anything to try. Thanks!

[prayers1 153]

I'd have to look. It does have the terminal with the post.

[MikeStang 247]

Here's the problem ...You put a chevy part on a Ford and the Ford is rejecting it...Kinda like giving someone with Type A blood some Type B ...It just aint good all the way around haha.

Could be a bad cell on the Battery maybe? Take the battery and have it load tested...

I would get a quote on having the Old alt rebuilt...I had one rebuilt for my Pontiac years ago and upgraded some stuff inside to support the Taurus Electric Fan, electric fuel pump and stereo...I had already smoked one new Alternator and one reman so I had my original one rebuilt, Guy charged me like 75.00

And its still going strong

[danno 128]

This new alternator could be working ok, it is just regulating at a lower voltage. If you read 12.67 with the lights off, then you turn the lights on and it stays the same, that tells me it is charging. If it was not, you would see a lower voltage when you turn on the lights. Leave it running for a few minutes with the lights on high beam, and the heater fan on high. Then watch the voltage; if it stays the same after a 2 minutes, your alternator is working.

 

Also watch for the voltage when the engine is revved up. If the voltage increases, that says either the pully on the alternator is too large, or it might not be working. You can also take your alternator to some shops to have it tested, to verify it is ok.

[Midlife 814]

It is very easy to test the alt. to see if it is charging. Simply

start the engine and remove the positive battery cable, if it is not charging the engine will shut off.

 

No no no no! Please do not do this! This is how one blows the diodes in the alternator.

[prayers1 153]

Well, long story short. It was a 50 amp in line fuse from the Alt to the Solenoid. I bought it from Jegs to be on the safe side and I guess it worked w/o me knowing. This was preventing the Alt to charge. It was something so obvious but over looked.

 

In the end, I found that my previous Alt was on the frits, so better to find out know now then on the road and I did buy 2 mores fuses just in case.

Edited September 28, 2013 by prayers1

[LoneWolf2U 136]

Well, long story short. It was a 50 amp in line fuse from the Alt to the Solenoid. I bought it from Jegs to be on the safe side and I guess it worked w/o me knowing. This was preventing the Alt to charge. It was something so obvious but over looked.

 

In the end, I found that my previous Alt was on the frits, so better to find out know now then on the road and I did buy 2 mores fuses just in case.

 

 

Well one of those Doh moments, would have been nice to know it was fused.

As for the bubbles in the fuel filter, did you change the rubber line under the drivers floorboard?

Check the clamps on all of the connections, your drawing air from somewhere.