damn alternator

Brianas

Registered User
I put a ford reman unit in back about december last year and it just died on me--Now my stock alt lasted about 12 years
things that I changed on the car that might have effected the reman alt are underdrive pulleys and eec tuner
either I got a bad alt or 1 of those things did it in
any 1 have ideas--Josh
 
Hey that's not bad for a reman. I went through about 3 before the last one lasted more than a year.
I now only buy new electrical parts.
However, one thing that is critical to the life of the alternators in our cars is making sure you have a good battery. If you have a weak or dying battery the alternator overworks itself trying to re-charge it and they burn themselves out.
So before you put in another alternator, make sure it's a good fully charged battery, and also make sure the battery cables and connections are good, clean, and tight.
(I found a rotted, corroded battery cable on mine after only 64,000 miles.)
How many miles on your cables?
 
Another thing you might want to consider is how many power loving accessories do you have on the car.(stero amps, lights)
I dont know if you have any of these but if you do the underdriving of the alternator could be part of the problem.
You could be just working it to death while it tries to keep up with demand while its being underdriven. I dunno maybe this doesnt apply.
 
thanks for the input
The cables have all been replaced\upgraded--connections cleaned
the battery is 2 months old -optima red
there is alot of access. drawing juice
but the biggest draw I notice is the fan--it really seems to draw some juice-volts drop from like 13.0 to 12.5 when its on high
and I just put my eec tuner in yesterday-and the fan seems to run almost constant now-at idle any way
and the underdive pulleys spin the alt slower at idle-guess ur right it just burned out under the load
I tried putting the original small pulley back on the alt -but I could not find a short enough belt to fit it
thanks Josh
 
alright I just charged the battery up w a charger and started the carwith all acc off and fan off the volts were 12.4 at idle--I disconnected the battery while it was running and the volts shot up to 14.0 at idle I turned the ac on max and it worked volts dropped to 12.6--what the heck is going on--is it a weak alt or do I maybe have a bad battery
Josh
 
I understand your problem. Our alternators last like they were made out of glass. I have had to change mine out almost every year. I’m actually getting fast at changing it out! There are some threads out there which describe changing out our unit for other (more common and higher output) alternators. That is the route I will take the next time. You can find the info with a search.

Good Luck
 
Guys i'll tell you you a lesser known fact about the alt. It was made by Mitsubishi just thought that might come in handy if you was looking....to...I dont know......cross refference alittle sumpin sumpin.;)
 
Mitsubishi? I could have sworn our alternators were Denso Units.....


Anyway, what you might want to do is bump up your idle speed in the EEC tuner. With a set of underdrives tha alternator just cannot supply proper voltage at a low RPM, especially if there is a heavy electrical load at the time.

Vernon had a pretty decent post about this somewhere, basically he bumped his idle up to close to 1000 RPM to get a steady voltage with underdrives.
 
On the other hand you could ditch those useless UD pulley's and put the stock ones back on and enjoy having plenty of power.:)
 
As I have said before, the amount of horsepower gain you get from UD pulley’s is hardly worth the trouble. Unless you are running the car on the track, and milliseconds count, they are a waste of money.
 
Brianas said:
alright I just charged the battery up w a charger and started the carwith all acc off and fan off the volts were 12.4 at idle--I disconnected the battery while it was running and the volts shot up to 14.0 at idle I turned the ac on max and it worked volts dropped to 12.6--what the heck is going on--is it a weak alt or do I maybe have a bad battery
Josh
Actually, it could be both. Start by having the battery tested. If it tests OK, then have the alt tested. You'll have to take it off the car for this, but even a puny alt can put out 14V with no load on it. It sounds more like a weak alternator. They can test it under a load at just about any auto parts store.
 
well I got the original pulley back on the alt and Of course I still couldnt find a belt that fit--so I used the stocksize belt and spaced the ac compressor out to take up some of slack in the belt. any way the battery is fine and stays charging--volts drop to about 12.6 with lights-ac-fan all on at idle
thanks for all the help
now i gotta look into getting an upgrade alt and belt that fits
Josh
 
Youre still underdriving it though. With only 12.6 volts at idle youre not charging the battery.
Just get rid of the UD setup and be done with it, its not helping you.;)
 
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