wildwestsydney

Hi 1984 euro 5 spd. Replacing alternator and trying to install shroud that was non exhistant when I bought the car. Alternator bolts in fine but I can not see any way to install the shroud on this alternator. I got both the shrouds from 928srus the alternator came with the car but was not installed. I have attached a pic of the alternator ant the two shrouds. when the alternator was out I can see no way to attach the shroud, there are no bolt holes or studs to line up with either shroud. Also with the alternator in the car I see no way that the shroud would fit without interfernce. I am thinking that this may not be the correct alternator for the car. The alternator looks like any 928 alternator that I have seen a picture of.

Any thoughts

bronto

I've been wondering the same thing on mine. It's a '79 with a Bosch replacement. I've been told that it's not possible to put a shroud on the Bosch, so I'd like to know what will work when the Bosch eventually fails.

smudaaar

this is what it should look like to fit a shroud

wildwestsydney

Have you been driving without a shroud? have you had any alternator problems?

thanks

j.kenzie@sbcglobal.net

I drove with a bosch replacement, similar to yours, for about 2 years with no real problem. I also ordered a shroud and tried to fit it but could not. Ultimately I replaced with a high output alternator. Probably the most direct overall repair would be to acquire an original alternator (Paris-Rohn?) which is made to fit the shroud and re-enable the cooling duct including the ambient air temp sensor. Roger has rebuilt units, I think, and other sponsors may as well. The original alternator is probably OK when you don't add electrical updates such as stereo amps, electric fans etc.

bronto

I have a problem where the exciter doesn't engage on startup until I rev it up to about 1500 rpm, but I don't think that's shroud related.

I have been told that I likely will have problems, but I also rarely drive it in high heat conditions. Either I am driving a short distance at low speeds or a long distance and high speeds. I've been told that the shroud is crucial in hot stop-&-go traffic, but I don't encounter that very often. But I am expecting to have a problem someday, so I am making a plan...

bronto

I have 2 relatively low power amps added by a P.O. I would feel better if I had a higher output alternator though. That's why I'm asking. Obviously, going back to original will work. But what other options will work, including H.O. options?

Brian B

I have a Bosch alternator in my 79 that the shroud bolted right on to. Got the whole setup from 928 Specialists.

The alternator excitement problem might be the resistor on your voltage gauge. I replaced this when I put the Bosch unit in and I haven't had any problems with charging for more than 5 years now.

bronto

Then there must be different Bosch alternators. Any chance I can get a part number from yours? How many amps is it?

Alan

If your alternator doesn't generate until 1500 rpm - you probably don't have an exciter circuit... many alternators will self-excite at high rpms due to residual magnetism in the rotor - even with no excitation current. You probably have a damaged resistor (maybe its just the bulb left...) - assuming that you still have the alternator light in the dash?

Alan

bronto

Yes, there's an alternator light in the dash; that's what I'm watching. The light goes off at around 1500 rpm. I don't believe it's lying because there's a visible difference in dash illumination intensity then the alt light goes off.

IIRC, we replaced the resistor early on (18 months ago?) when I had a battery drainage problem, which was ultimately solved by replacing one of the mentioned amps the PO added.

Brian B

From the 928 Specialists Web Site

Alternator 77-84 Bosch Rebuilt* 928.603.114.AX $170.00

Alternator Ventilating Cowl 77-84 (Updated) 928.603.133.04 $32.18

Alternator Cowling Gasket 77-84 (Updated) 928.603.135.02 $8.01

Alternator Charging Resistor 77-84 928.641.981.00 Genuine Porsche Price: $10.70

Hope this helps...

ROG100

The older PR alternators are not availabe any more and the upgrade is a Bosch unit as were most of the alternators from that era onwards.
The picture in the first post does not look like a 928 Bosch alternator.
All the alternators were fitted with a shroud and have a cooling hose fed from under the drivers side fender.
You will need a different alternator if you wish to fit a shroud.
If you buy the later style Bosch 928 alternator they insist on the shroud otherwise you void the Warranty due to overheating issues.

Wild West Sydney,
After you received the first shroud - which was correct for your model year - you sent me a picture of what you thought your alternator was. That picture was of the later Bosch 928 unit.
No problem sending the shrouds and gaskets back.
Best,
Roger

bronto

Roger, is a higher amp version available for mine?

bronto

Darn, I missed my 928th post