stangman33

ok guys i found a write up on how to install the 3g alt on my 90 gt. i wired it up exactly how it stated. i have run a 6gauge wire to the solenoid. i would have used 4 but 6 was all that was available. so ive moved my battery and starter solenoid to the rear of the car, it cranks fine so i know the solenoid is grounded fine. but when it starts it doesnt charge what so ever. i bought the alt out of a junk yard, which could be the problem. the guy gauranteed it to be good and said would swap it out if needed. but i kinda have a feeling thats not the problem. can any of you give me a slight idea of something else to look at before i try to get a new one. this alt has the threaded top bolt, so im assuming it was a 130 amp alt. but even if its not a 130 itll still show charge at the battery with a voltmeter right? please help

mustangGT86_05

I did the swap and had no charge, it ended up being the alternator. If anything check to see if there is voltage going to your stator pickup

9550

question regarding this 3g alternator swap thing
whats the deal? why do i see this coming up? whats the 3g do that regular stock doesnt?

mustangGT86_05

3g is an 120 amp alt vs the stock 45. Basically if you plan on adding electrical equipment such as say a sound system or an electric fan conversion, etc then its best to do this upgrade

9550

got it.thanks

stangman33

alternator tested good at 15 volts when i took it and had tested earlier today. i got back and hooked it up back on the car and nothing. on the back post it was saying 15 volts on the multimeter, but at the battery and solenoid it was only reading 11.8-12 volts. somebody help me please.

mattdel

15 is high. Most all alternators are regulated to stop at 14.8, and most generally only put out about 14.3-5
Most regulators that don't follow their design often can be seen hopping around between 6-19 volts, but you need a high speed meter to see it. It's terrible for the battery.

Tony71502

Had no issues with underdrive pulleys on the stock alternator for over 3 years.

This is what I'm using now. No problems. 160 amp.

http://www.pa-performance.com/Script...?idproduct=343

I hid the fuse in the driver's side wheel well and hid the wires under the radiator support. Can't even see it.

stangman33

i can understand that 15 is high. but i guess it doesnt matter how high it is if its not making it to the battery. so now what

mustangGT86_05

Are you sure you have a good connection on the output post? I mean you have 2 paths to your battery now, the factory wiring and your wiring. If there is NO voltage making it to the battery you may just not have it tightened all the way. Is your aftermarket wire fused? If so is it blown? Find out and let us know