Squeaky Alternator

[688i]

My alternator has had an anoying squeak at idle and has been this way for months. You can't hear it inside the car and it stops with speeds above idle. I can spray silicone spray in the pully area of alternator and it will stop for a few minutes then start again. Should I be worried about a bearing failure and can you replace just the alternator bearing(s)?

[HotZ28]

I assume you have a PA, if so what year? Is the alternator a CS130, or CS144? Are you sure that the squeaking noise is not the belt or idler pulley?

[688i]

Yes it is 1996 PA and I'm sure the squeak is the alternator. If I spray silicone into the face of the alternator/pulley area, it will stop squeaking for a few minutes. I will have to get back with you on the model of alternator.

[HotZ28]

Both of the alternators use double sealed ball bearings (front & rear) & permanently lubricated. IF the seals are intact, it would be impossible to lubricate the bearing with silicone spray. Now, if for some reason the bearing were worn enough that the seal has popped out, you may be able to get a small amount of lube to the bearing. However, in this event, you would have much more noise than a squeak. Squeaks are usually traced to an idler pulley or glazed & hardened drive belt. A few drops of silicone lube dropped on the belt, or pulley would quite the squeak for a short period of time. If you think you may have front bearing wear, most auto part stores still offer rebuild kits for these. It might be best to get a second opinion from your mechanic, or a Starter/Alternator shop, on the source of the noise before tearing into the alternator.

You can check the SPID sticker on the spare tire cover to identify which alternator you have. Look for KG9 or K68. In addition, notice the visual appearance in the two sizes below. The CS 130D shown, has an internal fan arrangement while the CS130 (shown in last pic) has an external fan; the CS 144 comes only with an external fan. The SPID codes are shown below:

KG9**GENERATOR 140 AMP (CS 144)

K68**GENERATOR 105 AMP (CS130D)

[688i]

After reading your very informative post I'm thinking I don't have a bearing problem. I have the KG9 alternator. I replaced the tensioner arm and associated pulley about 1 year ago and it is working fine. I replaced the serpentine belt about 15,000 miles ago. They should kick the engineer's behind that designed the motor mount you have to remove for that job. Without looking is there another idler pulley that could be squeaking? Thanks for your good posts.

[HotZ28]

The KG9 is the CS144, more common on the Ultra. Is your car an Ultra? What kind (brand) of belt did you install. Do you have a plastic or metal idler pulley? BTW, you dont have to remove the motor mount to install the belt, just the spacer on the right lower side!

[688i]

No it's not an ultra and removing the spacer is what I mean't but it's essientially the same thing, i.e. it seperates the body and engine support. I'm used of the belt replacement being a 10 minute max job instead of a 90 minute floor jack support assist job. The tensioner had a plastic pulley and the way they designed it is a less than an adequate engineering design also IMHO. It takes very little force to strip the pulley bolt and requires a considerable amount of force to relax. They should have designed it so that you didn't need to use the bolt as your pivot point. A 1/2 inch rachet slot on the bracket would have been much better. I'm not positive about the belt but believe it was a gates. The noise sounds like it is coming from the alternator area and is a contiuous squeak.

[HotZ28]

Originally Posted by 688i

No it's not an ultra and removing the spacer is what I mean't but it's essientially the same thing, i.e. it seperates the body and engine support.

I am sorry; we must not be talking about the same part of the front motor mount. The stud/spacer that I was referring to is located behind the mount and bolts to the engine, not the body. If you look closely, the bracket that is bolted to the engine has several studs with nuts holding the bracket in place. If you look at the bracket, you will notice on the bottom front stud, (lower right side looking from the fender-well) there is a spacer between the bracket and the engine. The nut will need to be removed first, then the stud in order to remove the spacer. The stud has a male Torx arrangement on the end and you will need a Torx socket T-10 or T12, (I forget which) for removal. Once the stud has been removed, the spacer can be pried out. After the spacer is out, the belt will slide through the opening between the bracket and engine block. I normally grind a slight angle on the spacer while it is out in order to help ease installation and future belt replacement. Click Here for a recent thread on the subject.

[688i]

We are talking about the same piece. I did mine just like the below pasted thread.

My 98 leSabre has a three point motor mount. The belt runs through the middle. The lower mount is a light brace; it doesn't seem to really support much.

The mount is a spacer tube a couple inches long. It's held in place by a stud. Remove the stud and the space tube comes out and the belt comes through that opening!!!

Jack up the right side of the car. Pull the plastic splash shield out of the way and prop it with something. You might want to take the wheel off and lower the jack some. There's nut around the stud. Then the end of the stud has a torx male end. Requires female torx socket. I don't recall the size. Check yours out since it's two years earlier, it may have a different setup.

The suggestion is to support the engine lightly when removing that stud. You're not supposed to use a piece of wood lightly under the oil pan, but some do. I saw someone raise the left side of the car slightly to support the motor. They left the wheel in place not jacket up.

[Jrs3800]

For replacing the belt, you can pull the splash shield... Unplug the crank sensor( simply to avoid damage )... Remove the 18mm Nut... Then you need a Torx E-10 to remove the stud, then the spacer can be removed( may take a little force )... From there you remove the belt and reassemble.... Its really not that hard..

Having to do the water pump on these cars is pretty easy as well.. Now on a series I the water pump is a slightly different story

[HotZ28]

Well, it is good to know we are on the “same sheet of music” on the belt install! Now let’s get back to the “squeak” you are hearing. I have a 96 Ultra SC and recently replaced all the idler and tensioner pulleys, along with a new Dayco poly-v belt on the accessories and a Goodyear Gatorback on the Supercharger drive. (See the Gatorback double rib belt below)The Dayco belt is very quite, no noise at all! The Goodyear Gatorback belt had a “bird chirp” noise @ idle! I found that the tensioner pulley was out of alignment with the idler pulley. I had to fabricate a stainless flat washer & install it behind the pulley to get the pulley aligned with the other. (See pic below) This procedure put the belt in the center of the pulley, instead off to one side. A new pulley will have a slight crown in the middle and it is difficult to get the belt centered while running. When the pulleys are out of alignment, the ribs on the belt make a “chirping” noise when they transfer from one pulley to the next! This problem seems to be more prevalent with Goodyear belts than Dayco or Gates, however, the Gatorback belt will not slip under full throttle. That is the reason I installed a Gatorback on the SC drive! BTW, never ever use belt grip, slicone, WD-40, or any other material on a Serpentine belt!

[688i]

Well I have obviously already gotten silicone on the belt when I was doing the alt. pulley. Hopefully not enough to screw up whatever it does that's not desired. I will say that the squeak stops for a short period of time when I spray the silicone though. Mine doesn't sound like I'm thinking a chirp would sound like. I think I will leave alone for now. Does your alt. case get hot from normal engine run?