I mean, who of us rebuilds them? My front bearing seems to fit too loose on the rotor shaft. It has to be pressed into the front housing, but almost drops onto the shaft. Although I can't see anything to indicate this is happening, I'm afraid that it is loose enough to allow the inner race to spin on the shaft. Both the old bearing and two new ones fit this way. I decided to try a little lock tite to help it out and threw it back together.

Anyway, the whole point of the chore was to get rid of what I though were whining bearings. It sounds exactly the same with the new ones. So the loose fit seems to be the next likely culprit to me. Any suggestions/input?

 

I have done many over the years, actually paid for high school that way many moons ago. Loved the old Delcotrons. Only thing to look for is scoring on the rotor shaft itself. Check for endplay holding the front housing on a bench vise. A small mag glass helps for evidence of shaft damage. If you need parts try www.alternatorparts.com. They stock all the parts for most popular alternators and they are reasonable. If you can, order the OE Delco stuff. Some of the generic parts they carry I am suspect of. There is a lot of really bad aftermarket stuff around. If I take it apart, I don't want to do it again in 6 months.

 

Danno,
Thanks for the input. I've been ordering from them for (unfortunately) a while now for my CS 130. First, about a year ago, I had some charging problems, so ordered the Iceberg conversion kit. That went fine and fixed my charging problem. After a little while though, I started to get a whine from my alt. I decided that they supplied low grade bearings, so ordered what I felt were quality bearings from McMaster Carr or MSC (don't recall which). Well, after installing them, it sounded the same. Gave it another shot over the weekend with bearings from www.alternatorparts.com. Sounds the same. It was this latest install that I noticed how loose the center race seemed to fit the shaft. I inspected the shaft under my flourescent light/magnifying glass, but saw no scoring or evidence that the race had been spinning. The only thing that I saw that could relate were a few brown marks on the inside diameter of the center race of the old front bearing. Not something I associate with spinning, but the only thing out of the ordinary other than the fit. I wish I had some micrometers to measure my shaft and some specs to compare to. Maybe I have to just cough up some cash and buy a new rotor. I know what you mean about not having to do it every six months. Unfortunately, that's what i've been doing.

MikeS

 

I am looking to upgrade my alternator in my Z..it is a 1982 stock replacement...63 amp I beleive.How do I tell what model it is?I want to upgrade the output of it and it looks to be cheaper to get one of the kits from alternatorparts.com and do it myself versus buying a new one.They have many different kits displayed...

 

I believe that on an 82 you'll have the 12-SI (which is a 10-SI type alternator). They have four different kits to upgrade the current output on those. Part numbers HO-7001 and SE-7001 are upgrades to 80 amps. Part numbers HO-7011 and SE-7011 are 105 amp upgrades. Once you decide how many amps you want, you just have to decide if you are going with the regular (HO part numbers) or self excited (SE) one wire kits. I think you want one of the HO kits, but am not sure on that. Lemme know if that helps at all.

All of the kits mentioned can be found here.

 

Mike, I looked in my parts cab and I don't have a rotor to mic for you. I have used several of the Iceberg kits and so far nothing like you describe. Problem with bearings is that when you go up in grade the prices increase logrithmically. Me thinks you have your finger on the problem however, not much else it can be.

 

Thanks for your help Mike..that is the kit I was looking for.

 

Danno,
Thanks for the input. I guess I'm just in denial. I guess I'll try scrounging up some change for a new rotor. I wish I had a plating shop to add some material to it!

1bad,
No problem, glad to help. Which one are you going with?

 

Going with kit #HO-7011...105amp upgrade...going to get the bearing kit also..might as well while I am in there.Any idea what is involved in changing the bearings?Pressed in or not?

 

I'm not sure what the bearing setup is on your alt. I've only done the newer style. For the record, on the newer style (CS-130), the only tricky one is the rear. The front is pressed into the front housing but is easy to remove. The rear is pressed onto the shaft and doesn't leave much room for a bearing or gear puller. I've read some of Danno's stuff on alternators before. I'm sure he's done more than I have. Maybe he can give some details on your bearing setup...