5.0stang.ryan

I just did a 3G alt install on my 90Gt. The battery gauge inside the car does not go past half now. I switched the pulleys and put the stock pulley on the new 130Amp alt. the alt is a reman off a 94 taurus. I used 4 gauge power wire and everything is connected properly as it is working just not as good as i suspected. Under major loads it will go down for a second when something is turned on and then will return to half when driving down the road or even at idle. With the old 75 amp alt it went past half when at mid rpms that is why i am confused as to why it is doingthis now.
Any coments would be of great help
Thanks

Five0hFox

Common law around here says that if your referring to the stock battery gauge, it's basically just saying, "hey I'm working." if you really want to know what it's putting out, get a new gauge.

lxman1

Yep My stock gauge reads all over the place. My aftermarket gauge under the dash never goes below 13.5 even with everything on including electric fan.

Tony71502

The instructions with my 3g alt said do not change the pulley because of how the alternators are assembled. It voids warranty and could cause problems.

I don't know how true it is but I'm just saying.

motorman524

My stock one does it as well and I did the conversion. I am saving for this: http://www.florida50.com/1987-1993-i...t-clusters.htm
I will wait until next winter to buy and put it in though.

5.0stang.ryan

Well i had another set of problems today. Like an idiot i forgot my lights on for a good two hours and killed the battery. Jumped it and the alt was no longer working correcly and blew my 150amp $18 circuit breaker i had on the power wire. Well i turns out the guy at adavanced auto looked into this and the reman unit i baught will overheat when the battery is dead. I am hoping this was my problem. I was able to return and get another reman unit and it is currently working ok now. Dont have an inline fuse right now i am gonna get that tomorrow just dont want it to smoke another 18 buck circuit breaker. I found that only way to spin the alt fast enough was to change over the stock pulley.

lxman1

You should never try to charge a dead battery with an alternator. They are not designed for the long, heavy load. They usually say that in the instruction paper that comes with them. It will say to charge the battery first.