tmpusfugit

I am now up to a sample size of 4 alternators, all of which have been rebuilt at one time or another. 2 are for 928's, the other 2 are for other model Porsches and out of a buddy's reject stack. Results?

one with extremely worn slip rings, pictured previously in this thread

none of the 4 had brushes replaced. All were worn to apparently 1/2 original length or less. I did order 1 new replacement regulator with brushes just to see if that solves any problems, have not yet received those. Should be interesting, but won't prove anything.

one has a very noisy bearing (front)

the one from fleabay that drops to 11 vdc with the car headlights on and running at 2000 rpms had no key in the keyway when received, suggesting very sloppy work. I also suspect a bad diode on this one but have not yet verified what is wrong.

Not exactly a sterling recommendation for "rebuilts" from multiple sources.

Maleficio

tmpusfugit,

Did you get your ebay alt from these guys?

http://cgi.ebay.com/ebaymotors/ws/eB...K%3AMEWNX%3AIT

I got mine from them, and it was missing the key, too. It took me two hours to file down my other one to fit the new one. The bearing is a little noisy, but it seems to be working okay so far, as long as I've got the idle set right.

The alt I took out is a Valeo, and I wonder if I should rebuild it for next time. It's actually designed for the cooling shroud whereas the new one isn't, though it's a Bosch.

danglerb

Eagle Auto Electric is the same I used about 5 years ago for updating alt in my Mustang, still working fine.

Maleficio

Cool. They did not do a very good job with mine, though it was a great price. You get what you pay for, but I'm happy I got it working. My voltage issues are gone.

Though I do wonder about replacing the field wire completely. It does not feel healthy at the alt end.

tmpusfugit

Yep, these are the folks from where the fleabay alternator came from... http://cgi.ebay.com/ebaymotors/ws/eB...4877&viewitem=

to be precise...and I have the same problem with the cooling shroud too....I have 2 shrouds, one new (later) style and one earlier, and neither fit...

Maleficio

I'm thinking of taking my sump shield and cutting a slot in it and bending the metal downward so that air will be scooped in and fed directly into the face of the alt. The alt looks like it might be in a place of static air movement.

tmpusfugit

Just a thought, but the original shroud system was to 1) deliver fresh air to the alternator and 2) keep out dirt/grit/road debris and the like...just forcing air on it might put even more dirt into it....would it not?

Landseer

Guys make it easy on yourselves.

dr bob

The airflow through the alternator is rear-to-front, with the front fan a radial-discharge type. 'Scooping' air and junk into the front won't help at all with internal cooling.

Check with Mark or Tom at 928 Int'l for their info on their rebuilder. It isn't too hard to see that paying some extra up front for a known-reliable rebuilt, from a known-reliable supplier with a serious community reputation to maintain, that happens to be an exact fit including the cooling shroud attachment, is a better deal than two or three questionable but cheaper units that don't exactly fit with the cooling shroud and come sans Woodruff key. As much as I love laying under the car with the pans off, finessing the alternator into place and getting everything attached again, I love even more that I only needed to do it once, and it worked perfectly once installed. I put all the belly pans back on before I bothered to start the car and look at the voltage readings. I'm not sure I'd be that confident with a junk-yard spray-cleaner 'rebuilt' unit. The 'lowest-cost' unit is not necessarily the cheapest in the end, and it sounds like it may not be the 'best value' either.

Maleficio

The shroud only covers the back of the alt.

Ducman82

does anyone have a picture of a mod shroud on a Delco alt? i was under my car today and i know the plastic shroud will not fit over the cast back half of the Delco.

Maleficio

You are exactly right. No argument here.

But I've got my el cheapo alt working great, and I'm going to leave it on there until I can get my Valeo rebuilt for standby.

Right now I've got a bigger issue: one failed brake circuit. I can actually feel less braking power, and this coincides exactly with when the light came on yesterday. Am I correct in thinking that the master cylinder is like two brake systems in one? Two cylinders providing pressure that ultimately meet up in one line at the wheel with a check valve up stream to prevent one side's pressure from entering the other cylinder should it fail?

If I'm right, I need to replace the master cylinder. I know most people have been able to just change out the switches and were good to go, but I've actually lost braking power.

So the el cheapo alt can stay where it is for now.

I'm glad I was able to get a functional Central Warning unit ($30 off eBay).

Landseer

I run them nekked.


Sharkskin tried to shroud a higher-output Delco.

Check his round 21

http://members.rennlist.com/sharkski...Alternator.htm

Ducman82

The delco i have does not leave much room for attaching stuff. damn HOT engine bay....

LT Texan

freakin' Albuquerque Ducman82!!!!!