Sounds like an alternator going bad...

[CandyManChris]

Hey Guys,

So I think my alternator is going bad. I've been trying to find a NEW BOSCH alternator, but all I can find is refurbished ones for M6. Will an M6 alternator fit on my M30B35?? I didn't think so, but maybe? I can find NEW alternators from USA Industries, but I would like to keep everything that was BOSCH, BOSCH. Does anyone know where you can get new BOSCH alternators??

Thanks guys,
Chris

[alpinacsi]

Are you sure it is the alternator. Generally just the voltage regulator fails and it can be replaced without removing the alt and cost less than $30.

[CandyManChris]

Technically, no, I am not 100 percent sure it is my alternator. My engine bay has been really load the last couple of days and I popped my hood and took a listen and the sound is definitely coming from my alternator, but I am not sure if my alternator NEEDS to be replaced. I have to take the car in tomorrow to get my mechanic to take a look at some suspension stuff, so I have asked him to take a listen to see what he thinks. Basically the alternator is making a "WHEEEZING" sound as the belts are turning.

Chris

[alpinacsi]

Technically, no, I am not 100 percent sure it is my alternator. My engine bay has been really load the last couple of days and I popped my hood and took a listen and the sound is definitely coming from my alternator, but I am not sure if my alternator NEEDS to be replaced. I have to take the car in tomorrow to get my mechanic to take a look at some suspension stuff, so I have asked him to take a listen to see what he thinks. Basically the alternator is making a "WHEEEZING" sound as the belts are turning.

Chris

Probably need to replace the bearing and then for good measure I would put in a new regulator. If you are handy with a few basic tools you can do this yourself for far less than a cheap reman.

[M6csi]

When the alternator and the belts are making loud noises, sometimes this indicates the alternator mounting pivot bushings are shot. When this happens, the defective bushings will allow a lot of play, causing alignment issues with the belt and the other pulleys that are attached to it, thereby generating loud squealing and screeching sounds.

On the other hand, your alternator may be shot also. But, try the cheap bushings fix first! Oh BTW, there are alternators that do not use the hard plastic bushings and just have non-removeable metal sleeves. Check which version your car is fitted with.

[JRanmann]

As M6 says it's likely the bushings ... take a line of sight along the alt. belt and see if the pully ln the alternator is exactly in line...if it's not the front bearing is subject to forces that cause it to fail...

On my 83, the alternator (new Bosch) has an internal regulator and if not a bearing failure it's likely one of the 3 diodes has cracked or failed in some other respect.

lastly... if you can, lubricate your belts with spray belt dressing but old cracked belts need to be replaced...do them all at once as they often need to be removed anyway to get the alt. belt off over the fan pulley.


Ran

PS I would be more concerned with that ping sound happening every time you close your passenger door!

[alpinacsi]

I thought the 88 model alt came without the bushings in the mount? But that is a very good thing to check and replace if needed. Worn bushings can cause the bearing to fail as well. from my experiance, the BMW alts are built like tanks and rarely fail other than the bushings, the bearing or the regulator. Some people call it an internal regulator but it can be accessed from the outside of the alt and replaced while the alt is on the car.

[CandyManChris]

So, funning thing happened today. I was driving with my mechanic as he was feeling my suspension issues. We pulled into his shop and we popped the hood. The alternator was a little load as we pulled in. We he shut off the engine and did a quick inspection on the belts. There were a few little cracks. He suggested that I replace them sooner rather than later. He then gave the belt a good firm tug, locked the hood and I drove away. The alternator was INSTANTLY quieter. I think it is only a temporary fix, but I was surprised that my issue seems nonexistent now.

BTW, there was a seminar in the building I work in and a bunch of super cute 20 something year old girls were just taking pictures of themselves by my car. What I would do to be out there with them right now. "Now, pour some water over those white shirts and say CHEESE!"