Alternator bearings

[PEAR0119]

Well, after replacing the tensioner and idler pulleys I finally got rid of a lot of bearing noise from the front of the engine. But now with them being quiet I can hear the alternator bearing grinding and squealing.

So I took the belt off and turned the alt. by hand, and realized that it is in fact the alt. that is causing my noises. if I turn it clock wise I can hear a grinding noise in certain spots in the bearing, if I turn it counterclockwise the rear bearing squeaks quite loud.

Has any ever replaced the bearings in their alt.? If so was it very difficult? And are there any additional parts that I would need besides the bearing? I have checked the voltage and the alt. is still working well so there won't be any need to replace anything else.

 

[PEAR0119]

Anyone?

 

[PEAR0119]

Alright, so I have replaced the bearings and it was completely quiet until I took the paper clip out out of the voltage regulator to release the brushes. Now its making the same noise as before, squeak and all. The rear bearing was completely shot, it was so loose.

Is it normal for the brushes to make noise when the alt. is turning?

 

[Robert Nick]

It could be Electro-Magnetic Noise. Brushes and Brush-Holders usually don't cause any Noise. You can cleanup the Rotor Slip Rings with Emery Cloth. Does the Noise change when you load the Alternator (Headlamps High Beam/Blower Motor High Speed/Rear Glass Defrost Grid all ON) to see if it is Electrical Load Dependent? Is the Battery Original with the vehicle? I have seen excessive Load on Alternators when One Battery Cell was Defective.

 

[PEAR0119]

The original battery took a crap on me this winter and have had the new battery for about 3 months now.

I have not put the alt. back on the car yet. Just spinning it by hand it makes the noise. Its just that once I put the entire thing together I spun it with a paper clip still holding the brushes down and it made no noise. Once I pulled the paper clip out to release the brushes it started to make noises again.

 

[Robert Nick]

Is it possible to buy New Brushes for your Alternator? If not, I would reinstall it and evaluate it under load. It might be OK since you replaced the Bad Bearings.

 

[PEAR0119]

Thats the plan. I know that it was charging properly before I took it out, it was just the noise that was bothering me. The noise went away once the engine warmed up, so I am assuming it was the bearings that were bad. since the brush noise was still there when the engine warmed up.

Hopefully I didn't screw anything up on the disassembly and assembly of the alt. Cost me $40 (SKF) in bearings so it better not make any noise.

 

[Robert Nick]

Good Luck. I think the $40 spent on the Bearings was a good decision. It is much cheaper than $200 U.S., for a Reman. Alternator.

 

[PEAR0119]

Thanks man, I like to think the same thing. If the noise goes away perfect, if not I will just bring it in to Ford and get it replaced under the extended warranty. Only reason I didn't do that to begin with is cause I have a $100 deductible so if the $40 bearing fixes it I am better off. I will be putting it back on the car tomorrow, so we will see how it goes.

This is the first time I have ever taken apart an alternator, but really there isn't a whole bunch to them. Replacing the bearings was pretty simple actually.

 

[mechanic62]

I'm not so sure about this decision. Hindsight being 20/20, before replacing the tensioner and idler pulleys and replacing the alt bearings, you would have certainly been better off using the warranty you paid for.

 

[PEAR0119]

At the time I thought for sure that the noise was coming from the idler, so I replaced that being only $30 and helped but didn't cure it. Then I looked at the tensioner and noticed that the pulley bearing was really bad, so I replaced it for $40. So I was thinking OK $70 is still less then the $100 deductible. At that point I have already spent the $70 for those two which did quiet down the noise but there is still noise up there. I noticed it coming from the alternator, so instead of paying another $100 for the deductible on top of the $70 I had already spent I thought it would be better to replace the bearings in the alt. for another $40.

So, $110 < $170. Now, I do realize that if the bearings do not fix the noise I will spend the $100 and get it fixed under warranty. Which means now $170 < 210, and I would of been better off just going warranty in the first place. But, I was trying the cheaper routes first in anticipation that they would fix the issue. Sometimes you save money but other times you spend more money in the long run. To me it was worth a shot.

 

[mechanic62]

I hear ya. Like the song goes, sometimes you're the windshield and sometimes you're the bug! On the bright side, you learned about gutting an alternator!

 

[PEAR0119]

Yeah for sure. I would much rather do work on my own car then let someone else do the work, not only because of the fact that I trust myself, but the fact that I like working on cars. I like getting my hands dirty and learning new things. The only way for me to learn is to do the work myself. It sucks that it may cost me more money in the long run on this one, but as you said, I now know how to gut an alternator .

 

[PEAR0119]

Well, I finally got the alternator back on the car!!!! The car is silent once again, oh and it still works after me tearing it apart so thats an added bonus. Feels so good not having annoying noises coming from the engine, plus I have the added feeling in knowing that there are new bearings in there and they are not going to fail. That little rear bearing was really close to failing when I took it apart.

 

[Robert Nick]

Glad it turned out good for you. It always feels good when you can fix it yourself.

 

[PEAR0119]

For sure, now it has to go in for emissions testing tomorrow . The hardest part was separating the halves of the alternator, other then that it was quite simple (granted if you have to properly puller for the rear bearing). Now I know that I can do this, there will be no replacing the entire alt. I am just going to rebuild it.

 

[Phantom]

Anyone happen to have bearing part numbers for the two?