Alternator for my 1983 S

MPDano · MPDano's Garage

Is this the correct one for my year?

Duralast Import/Alternator (13122) | 1983 Porsche 928S 8 Cylinders B 4.7L FI | AutoZone.com

It's a 90 amp. What is stock on our cars? 75 amp?

If so, will the air scoop work on the 90 amp model?

SMTCapeCod · 08-12-2011, 06:26 PM

Are you sure the OEM one is junk?

I replaced the brushes in one, and that took care of low output. In another instance, I took out the alternator, brought it to an auto electric shop and requested a rebuild without getting into what it came out of. Cost $90, worked great. I think that was one of the Paris-Rohn units. Just saying, why toss something if there isn't a need.

MPDano · MPDano's Garage

I told myself I will NEVER get my alternator rebuilt. Long story short, did that, headache, small claims and won. But still lost $$. Not worth the aggravation I went through just to do it again. We ended up getting a Reman for the BMW and never had an issue with it. Hence my going for a Remanufactured Alt.

MPDano · MPDano's Garage

Here's pics of my Alternator. I wanted to verify what I had. Took it around to all the local Auto Parts place and none of them can get them. Pep Boys and NAPA all recommended a well known Rebuilder in San Diego. Need options.

neil30076 · neil30076's Garage

Leo, that's a Paris-Rhone - replacement is Bosch AL325 - X for a rebuild, N for a genuine new - see this link!
It may just be a bad/weak brush set - worth removing to check first.
alternator/wiring help please

stepson · 08-16-2011, 10:51 AM

Quote:

Originally Posted by neil30076

Leo, that's a Paris-Rhone - replacement is Bosch AL325 - X for a rebuild, N for a genuine new - see this link!
It may just be a bad/weak brush set - worth removing to check first.
alternator/wiring help please

+1 I think that the brush set can ordered from most parts stores and are something less than $35. It is also easy to check the diodes, which are under the little round circles. Just make sure they are all attached (soldered) on both ends of the diodes. You could also check with Roger. He may have a deal for you.

Danglerb · 08-16-2011, 02:08 PM

What about the 88 Camaro or whatever Delco?

Autozone etc. all contract with the cheapest rebuilder they can find, then buy in bulk to drive the price down even more. Big roll of the dice, better to hit the pick a part.

MPDano · MPDano's Garage

I ended up buying this one in Los Angeles County. The business has very good feedback with lot's of numbers. No Core so I will probably rebuild mine at a later date just to see if I can do it. Will keep all posted.

Porsche 924 928 Paris Rhone Alternator BOSCH # AL325X | eBay

MPDano · MPDano's Garage

I got my Rebuilt Alt today and decided to install it. I went to Autozone to have them switch my pulley for me since I don't own an impact wrench. Anyways, got it all installed and the last pics show the battery volt check at the post and battery with car off (battery sat and was low charged).

I started the car and measured at the post 14.5v, then about 30 seconds later is dropped to about 12.5v. So I went for a freeway drive to see if it looked like it was charging. I wasn't impressed as it barely went past 10v and at idle it would go under 10v (showing on dash gauge).

I parked in the driveway and decided to keep it running and disconnect the battery to see if it the Alternator was even working. As soon as I disconnect the battery, I got about 13.5 at the post. Would a bad battery do this?

Ok, removed the battery from my Euro and put it in and started it back up, I noticed the dash gauge show about 12v. Measured at the post at 13.7v

I'm a little nervous about driving the car to work tomorrow so I will wait to hear about what you guys think.

MPDano · MPDano's Garage

Danglerb · 08-18-2011, 08:55 PM

Below 12v is a dead battery or a dead cell if the battery is charged.

MPDano · MPDano's Garage

Ok, braved it and drove the car to work.

Symptoms:

1) On Dash Gauge I see 13v on the freeway
2) On Dash Gauge is see 11-12v on idle
3) On Dash Gauge the volt needle drops up/down slightly as the turn signal is on

What are your thoughts? Voltage Regulator?

MPDano · MPDano's Garage

I was looking around for the Voltage Regulators for the Paris-Rhone and the brand name "HUCO" is out there. Anyone heard of them or know of a better known brand?

neil30076 · neil30076's Garage

The last regulator I replaced on a P-R unit was made by Valeo

MPDano · MPDano's Garage

Quote:

Originally Posted by neil30076

The last regulator I replaced on a P-R unit was made by Valeo

Where did you buy it? Does my symptoms sound like the Regulator?

neil30076 · neil30076's Garage

I don't remember where, probably not one of the usual suppliers - it was over 20 years ago, and still going strong! Not sure i would suspect the alternator yet, does the battery charge and hold its voltage if you disconnect it and put on an external charger?

trucker677 · 08-19-2011, 08:25 AM

I would say take the car out go to a shop and get them to do a voltage drop test on it and see what it comes up with, make sure all of your connections are good and clean first. take it to a shop where they can print out the display and get them to go over it with you. I can't say for sure but I think autozone does it. I think that might narrow your problem down.

Danglerb · 08-19-2011, 01:30 PM

Quote:

Originally Posted by MPDano

Ok, braved it and drove the car to work.

Symptoms:

1) On Dash Gauge I see 13v on the freeway
2) On Dash Gauge is see 11-12v on idle
3) On Dash Gauge the volt needle drops up/down slightly as the turn signal is on

What are your thoughts? Voltage Regulator?

I don't trust on dash.

Disconnect the battery and put a full charge on it, then test it. Once you know the battery is good see how it does in the car again. If it doesn't stay charged, have the alternator checked/replaced.

Make sure the belt isn't slipping to the alternator.

MPDano · MPDano's Garage

Quote:

Originally Posted by Danglerb

I don't trust on dash.

Disconnect the battery and put a full charge on it, then test it. Once you know the battery is good see how it does in the car again. If it doesn't stay charged, have the alternator checked/replaced.

Make sure the belt isn't slipping to the alternator.

Understood, I don't trust it either, but it didn't do this with the "original" Alternator. I did forget to mention that belt is tight within specs.

Remember, I have my Euro Battery (Autozone), which is actually giving me better results. I will throw my Battery on my trickler charger tonight, and get my "other" battery (Wal-Mart) checked. Should I try and charge the Wal-Mart battery before bringing it in for a check?

With perfect battery cells, what should I measure as far as volts?

neil30076 · neil30076's Garage

Leo, each battery has six cells that generate 2.1 volts. A car battery is fully charged at 12.6 volts - and most will show this even when they cannot supply the load - so not a meaningful measurement, unfortunately.
Charge the battery on your trickle charger until the charging current drops to about 1/1000 of the batteries rated CCA. So if it is a 800 CCA, charge until the charge current is below 1 amp. Now take it and get it tested, as it is the best it can be !
With the battery back in the car, and engine running - put the meter across the battery - If the meter reads 13.5 to 15 volts, then the alternator is working - BUT - still may not be putting out enough amps to charge - to test this you need a clip on DC ammeter to see what current is flowing in the alternator b+ , and back at the battery - a clip on will show you if the alternator is charging, or consuming power, as well ( by direction of current flow )