motorhead102482

First off, i'm decently skilled when it comes to automobiles, but i'm just having some problems. My 90 mustang has a charging problem. It runs like the alternator isn't working. The battery drains as i drive it and i get no charge indication on my voltmeter. The alternator is new, and i have had it checked and the auto parts store says it's good. I checked the wiring to and from and all around according to the wiring diagrams and it checked fine as far as continuity goes. When i run the car i checked the voltages coming off the windings of the alternator and i'm only getting like 11.8 v. Also, my 90 has a lot of vibration when revving up to 3000 rpms or so. Would it be more likely that it is my flywheel or my driveshaft, or could it be my ujoints on my driveshaft. Any help or advice would be appreciated. also, i would like to know if there are any common places that oil likes to leak. I have some oil leaking from the back of the engine and i'm not sure if it's the valve covers or the head gaskets, would i see a lot more problems if oil was leaking from the heads other than just leaking oil. I"m not overheating and dont have coolant in the oil.

silver91gt

I had the same problem for a couple of months, and worked on it most of the time, traced every single wire that had anything to do with the alternator.
brought the new alt back to the parts store, and they tested it and they told me it was good.
finally, I convinced them to trade me for one from a 94/95 5.0 and I would pay the difference.
change your alternator to a 3G one from a 94/95 5.0.
it really helps

about the vibration, if it only does it when you rev it, it wont be the driveshaft or u-joints or anything, it might be your harmonic balancer on the front of the crank.
watch it when it is running, if it wobbles replace it.
I have had 2 5.0 mustangs, and both of them leaked from the back of the lower intake.

and my 91 leaks from the back of the oil pan gasket.

motorhead102482

are the wire hookups the same. Do you remember about the price difference or the total price of the new alternator. Also, how many amps should i get. Thanks for the reply i was beginning to think nobody out there was gonna help me.

motorhead102482

also my leak seems to be coming from the top side of the motor. I don't suspect the oil pan cause it's running down the bellhousing. I just wasn't sure on top of the motor would be more likely to leak. Ya know how some cars have there little qwerks.