P964C2

Well my fan hub bearing started clunking at the weekend after a 1000 mile drive. I could move the fan slightly so I knew it was the bub bearing.

Took everything apart and followed the very good guides on the forum.

However, the question is, should I replace the alternator for a stock exchange whilest I am at it?

The car has done 113K miles. It seems sensible to change the alternator on the basis that if its bearings were to go in the near future, it would be a whole load more work. But then if it might run ok for another 100K miles why bother?

It turns OK by hand and charges OK. Is it possible to gauge bearing wear on an alternator at all?

How many miles do these alternators last for on average?

Blown Away

I think my alternator failed at about 150,000 on a very cold night and left me waiting for the tow truck. Replaced both alternator, and the piece on the back (impellor) and hub on the recommendation of my indie porsche guys. Didn't want to do it twice.

Think about the RS hub bearing - only uses one belt. I went back standard though as I didn't want to risk losing both belts as i use the car a lot. Not sure if it works if you have A/C though.

Laker

if it were me, and I had to go in there already, i'd cough up the $200 and put in a new one. @ 113k, it has served the car well.

C24FUN

My alternator "failed" at around 110k miles. The good news was that it only failed because the carbon brushes wore down to the point that they were no longer making contact with the commutator. The brushes are part of the voltage regulator that attaches to the end of the alternator itself and the whole regulator assembly is only about $16 from your local auto parts store. I replaced that and it's worked fine since.

If you've got it apart and you don't have reason to suspect the alternator bearings are bad, just change the regulator. If you suspect the bearings or just want to spend the money to avoid a future repair, change out the whole alternator.

Good luck!

Jim G.

FeralComprehension

I just went through this same thing and since my alternator was working well but I didn't want to mess with it again for a while I took it to a well-regarded local reman place. It was $159, two year warranty, and the guys that worked there convinced me they knew their business. I was away but they claim or two day turnaround time.

I found the VR/brushes online, but couldn't find bearings so I just paid to have it done.

P964C2

Well thanks for your comments, I finally finished the job today. I fitted a standard exchange Bosch alternator, my local specialist couldn't get the parts at a reasonable cost. The communtator was worn on the old unit.

It is a lot quieter now!

The only comments I would make to anyone doing the job in the future is make sure you have a gadget for getting lost bolts out when you drop them below the crank pulleys. Use rags to catch them first of all to avoid the problem in the first place! Fish out screws and bolts with tough flexible wire and use a gadget (grab fork end) to get hold of the bolt and pull it upwards. Also use grease and WD-40 on the cable rubber grommet to get it to mate properly when you fit the alternator rear cover.

chris951

I replaced the my hub bearing and went ahead and replaced the alternator, my car has 123k miles. If the hub bearing is worn out, the alternator bearings are probably not far from being worn out.