A4 alternator?

seaspot · #1 05-04-2010

I need a new alternator for my A4 and after seeing how much they are, I started wondering if any of you all have used a different alternator on your A4?

An AC Delco off of many GM will fit, internal regulator, single wire hook up, and cheap.

Even a marine one for a Mercruiser would work and still cheaper than the one for the A4.

Has anybody else already done this?

CalebD · #2 05-04-2010

Is your old alternator really shot? A good alternator rebuild shop should be able to fix your old one if it is just a diode or two that are shot. The problem with a rebuild is that it can cost as much as $250 to have your alternator rebuilt and a new 55 amp alternator from Moyer Marine is only $217.50. The original alternators on the A4 are only 35 amps so a new 55 amp alt. may just be the way to go.
Moyer Marine Atomic 4 Engine Rebuilding and Parts
Or try an AC Delco alt. but you should not need much more then 55 amps of output. The higher the amp rating on an alt. the more power it uses from the engine to generate those amps.
I have priced some 'marine' alternators and I agree that they are very $$$. It usually pays to shop around and compare prices/products.
Good luck whatever you do.

jaschrumpf · #3 05-04-2010

I had my 35A alternator totally rebuilt into a 55A alternator by a local Baltimore shop. It cost less than $100 for the rebuild, so I'd definitely look around and get some prices from a local alternator/starter shop before committing to buying a new one.

MARC2012 · #4 05-05-2010

If yours is shot why not try to repair it yourself.Usually brushes if em,.\.,m

tommays · #5 05-05-2010

What ever you do PLEASE use the marine unit as the brushes are spark shielded to help with BOOM

cardiacpaul · #6 05-06-2010

PLEASE - take it to a rebuild shop.
Brushes are about 12 bucks, diode pack about 15, and regulator about 20.00
(along with a diff diode pack and regulator, can make the prestolite, or motorola, or the delco to push out 50 amps.)

seaspot · #7 05-06-2010

OK, I;ll bring it back with me this weekend and have a local guy check it out and see what he'll charge to rebuild it.

I was just a little shocked when I looked up how much the replacements were.

seaspot · #8 07-11-2010

Just an update. The alternator was wrecked internally and was not able to be rebuilt.

Since I have tons of ventilation in my engine compartment, I just went with an AC Delco, one wire alternator. 80 amps, with core exchange, I just gave them an old GM I had sitting around, $29.99 out the door.

Hooked it up and I now have a ton-o-charging.

sailingdog · #9 07-11-2010

Bad idea to go with an automotive alternator. IIRC, they are not ignition protected...and as such are an ignition source for explosions on a gasoline powered boat.

Quote:

Originally Posted by seaspot

Just an update. The alternator was wrecked internally and was not able to be rebuilt.

Since I have tons of ventilation in my engine compartment, I just went with an AC Delco, one wire alternator. 80 amps, with core exchange, I just gave them an old GM I had sitting around, $29.99 out the door.

Hooked it up and I now have a ton-o-charging.

seaspot · #10 07-11-2010

If there are fumes sure. The main difference is just the internal screen, which the old A4 alternator didn't have anyway. I figured that out when I took it apart.