924Board.org

[davethehypnotist]

I have a 1982 non turbo that seems to be eating alternators. I have put two on and have a third ready to go on as soon as I solve this issue. The alternator works fine for a few days and then goes dead or really low and doesn't charge the battery. It may follow when the lights and wipers ore on or at least a larger drain on the battery. but I can't be sure.

The charging light on the console comes on when the car is turned to on but goes off when the car is running. The car runs fine on the battery and I charge it after each trip. She is my daily driver so I need to get this fixed ASAP. Any idea's?? The grounds seem good.

I have momentarily taken off the ground from the battery and she still runs but not good. The Orileys guy said the last one was putting out about 30 amps and it's 70 amp unit.


Help

Dave

[fiat22turbo]

First: confirm your wiring between the battery, starter and alternator is in good shape. They get cooked due to the proximity of the exhaust.

Second: verify you have a good ground from the alternator to the engine block. They routinely fail.

Third: verify the ground from the battery to the chassis and to the engine block. I had to add an extra ground lead on my car.

Fourth: the factory provided a cooling duct for a reason, use it if you have it, track one down if you don't.

Fifth: verify the power connections and the grounds under your dash and in the engine bay are cleaned and protected to ensure all of the current is able to flow properly.

There is a tip on 924.org about adding an extra ground for the center console to help improve the function of the gauges by adding a ground to the stud behind the center speaker cover and connecting it to the ground harness for the dashboard.

Finally the alternator rebuilds available at parts stores aren't known for being the greatest in quality. So a newer GM Style CS-144 alternator, while more expensive will future proof you by providing more potential current:

http://www.924board.org/viewtopic.php?t=36143

Note: you'll want larger gauge wiring for a larger alternator.
_________________
Stefan
1979 924 Carrera GTS (clone-ish)
1988 944 Turbo S (Silver Rose)

[Rasta Monsta]

If it was my DD that I intended to keep for several years, I would replace the alternator harness, positive battery cable to starter, and battery ground cable to tub and to engine block.

This is all fairly simple wiring that wouldn't cost an arm and a leg to restore.
_________________
Toofah King Bad

• WeiBe (1987 924S 2.5t) - 931 S3

[davethehypnotist]

This one only has 78k miles on it and I put the last 5k on it.

Those wires are in pretty good shape by the exhaust manifold.

The ground all checks good with a DMM,

I took the cover off the original unit because it wasn't working so I have it but I haven't' put it back on. Surly it doesn't need to cool that much. It's an audi engine and alternator. One would think it would be better than all that.

I don't know if this help but the horn doesn't work. I haven't' checked the relay but I will.

I'm all up for getting the best from the car. Not sure about upgrading the alternator from it's OEM or a rebuild. I mean the original was in good shape and it failed. I think something is fishy.

[fiat22turbo]

Well your choice, we've all been working on these for a few years now and have seen and discussed several issues all related to various wiring calamities.

The wiring can look good in the protective sheath and be ruined internally.

A non-working horn could be the horn, the connections in the engine bay for the horn, the button on the wheel or the connections under the column.
_________________
Stefan
1979 924 Carrera GTS (clone-ish)
1988 944 Turbo S (Silver Rose)

[brian19600]

Listen up under the dash as you push the horn button. You should hear the relay clicking.
_________________
78 924

[ideola]

+1 on replacing the entire starter / alternator harness. There is simply no reason not to do this.

In addition, if you are having an intermittent ground problem in the alternator circuit, it will wipe out the voltage regulator. I suspect that you are not actually losing the entire alternator itself, but ground is probably being interrupted during engine operation due to vibration, poor connection, brittle or damaged wires within the insulation, etc. This will fry the voltage regulator, which causes the alternator to malfunction.
_________________
erstwhile owner of just about every 924 variant ever made

[davethehypnotist]

I don't hear the relay click and I haven't removed it to check it yet. There is voltage at the steering column and the horns have worked so I'll get to the relay after the alternator.

So in theory if this is a ground problem should I put an additional ground strap to the battery or to the car frame. Where should I attach it.

What if the harness is good and the ground is solid. What next?

[Rasta Monsta]

What if a frog had wings? One thing at a time, brother.


_________________
Toofah King Bad

• WeiBe (1987 924S 2.5t) - 931 S3

[davethehypnotist]

You have never heard of flying frogs?

Thanks for all the tips and stuff. I checked out every thread here on the subject and followed the suggestions before I even posted to the board. I'm pretty sure the wiring is in good shape. When I get a chance to replace it, I will.

I'll strap another ground on the new one when I put it in.

What about the dash. Where does the B+ wire come from to activate the alternator.

All my gauges work fine. The tach goes kinda crazy when I drive it on a low battery like when I'm headed home and I've only got a few miles to go and I'm saying to the car, just get me home baby and I measure and it's running on like 8 volts when I pull in the driveway. Hahaha the car does want to run. I'll say that for this gal.

[Harm]

[davethehypnotist]

Yeah Mine looks nothing like that hahahaha

I think my problem is poor grounding. I'm going to start regrounding some areas and adding some new grounds.

That's why my horn doesn't work. The steering column has a poor ground. I confirmed that today.

Let you know what I do and how it all goes.

[davethehypnotist]

Put on the latest alternator. Got to a shoot 30 miles away. Drove 10 miles with the lights and then the sun came up and I turned them off. It was an early call in downtown Atlanta.

Car ran great all day when we had to move it for different shots. We worked late into the night and driving home at 10 pm had to use the lights. Made it 20 miles and felt the alternator go out. It feels like the engine slows and has less power almost like a misfire or it's running out of gas. Limped into the driveway with lights barely glowing. Just barely made it home.

Going to go through and look at some other issues.

Anyone have a source for voltage regulators.

I've been buying the 70 models but looked at a Bosch that was 250. Should I go with something different?

[Ozzie]

I put a bloody big earth cable between the body of the alternator and the motor. Fixed all issues and even the dash light doesn't glow dimly when the lights are on.
Even with new starter/alternator wiring the charge light would glow slightly at night and volts were dropping until I did this.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

[davethehypnotist]

Have a new issue that showed it's head today. The wipers started the intermittent cycle and just kept going. Had to pull the relay to stop them.

My dash lights are good but they only dim when the battery gets low and the alternator isn't working.

I did find a source for both tie rods and rectifiers for the alternator.

Gonna put another rectifier on when it arrives today and redo some grounds on the engine and the dash. This may be a charge circuit issue.

Thanks for your input. Still need help with the dash ground system and the steering column grounding system.

Any helpful links?