wheel berring help!!!

ricktruss · 12-09-2001, 01:00 AM

Tonight i heard a new sound while my car was driving -- a clicking sound coming from what sounds like the rear right wheel. It only occours while the car is under strain -- either accellerating or decelerating. With the clutch in, the wheel is silent -- even while rolling at any speed. I have looked under the car, but i dont see anything leaking. I can only figure this could maybe be the wheel berring. Have any of you experienced this? Oh, and the clicking goes faster as the car goes faster.

also, if it is the wheel berring, is this easy for a very novice home mechanic with a Haynes manual to do? I have an 86 951. I dont know what to do, and i really cant afford to have an expert look at this if i dont have to.

Please help

rick

Lawrence Coppari · 04:02 AM

The wheel bearing is pressed on a 951 and is difficult to remove. Some shops use a large puller to remove the bearing from the trailing arm. I changed mine about 2 years ago by following the directions in the Porsche manual which involved removing and heating the trailing arm to 300 F. I pushed the old bearing out with a shop press that I have in my basement. The new one was pressed in by again heating the trailing arm and freezing the bearing. Unless you have a press or the stout puller, you won't be able to do it.

Check and see if the 32mm nut has loosened. The nut is at the center of the wheel. Mine loosened causing the bearing to go south on me. The torque on the nut is 500 newton-meters. Also, it is a single use locking nut.

Make sure the noise is not coming from a caliper. Once I had the clip that holds the pads in come loose. It made a clicking sound.

My 951 is an '86 also. Hope it is not your bearing.

Magnus_944 · 12-09-2001, 05:09 AM

Clicking sound? Sure it's the bearing? I would guess CV-joint? (easy to replace, but not very cheap...)

//Magnus

JonA · 12-09-2001, 05:13 AM

A bad wheel bearing is generally a deep growling noise. Check the brake for something loose and floating around. Also check the cv joints. My understanding is that they do fail after hi mileage and hard use and that they generally do emit a clicking noise. I'm not sure of the best way to definitely determine if the cv joint is bad. Perhaps someone else has a good suggestion on how to diagnose.
Hope this helps.
Jon Aborn

Lawrence Coppari · 12-09-2001, 05:18 AM

I agree, it certainly could be a CV joint. That is a lot easier to deal with than a rear wheel bearing.

Lawrence Coppari · 12-09-2001, 05:24 AM

Once at a track event, a student's car exhibited a clicking sound when we returned to the pits. The emergency brake mechanism had fallen apart inside the wheel hub and would make a clickingscraping sound. But my vote is for the CV joint.

Bob's944 · Bob's944's Garage

I vote for CV joints.... wheel bearings are making their noise from the weight of the car bearing down on the hubs, should be more of a constant sound. CV joints have more force put on them under accelleration and decelleration, so their noise is more evident at those times. Search the subject, there is a good chance you can flip them from right to left and have a quick fix to last you many thousands of miles.

Lawrence Coppari · 12-09-2001, 06:53 AM

And if you do flip them so they turn in opposite directions, make sure you clean the threads and torque them properly. If it were mine, I'd use some Loctite on the threads. Manual says to replace bolts whenever you remove them. I had a half shaft come completely off once - rather unpleasant experience.

ricktruss · 12-09-2001, 12:08 PM

Thank you guys! wow, this forum is very helpful. I also thought of the CV joint, and this makes sense to me too.

What do you mean by "flipping" the cv joint? do you mean flipping the right one for the left one? Do you think the entore joint would need to be replaced? or is there parts in there that i could simply replace (gears, etc)? As you may be able to tell, i know little about cars, but i would attempt to fix it myself if you think it is possible for a novice to do so. I have a Haynes manual -- do you know if the proceedure for this is in there?

again, thank you so much!

rick

Lawrence Coppari · 12-09-2001, 12:21 PM

There is no inside/outside for a joint/half shaft. All the wear is on one face because you drive frontward all the time. Put the outside flange to the inside on each side of the car so the other face of the joint gets some wear. In other words, put them on so they turn in the opposite direction.

ricktruss · 12-10-2001, 07:13 PM

Thanks....that makes sense....although i do think i heard the clicking sound in reverse as well. would that matter?

Lawrence Coppari · 12-11-2001, 02:52 AM

Before the halfshaft fell off I had the old ones rebuilt which would have been ok for just driving on the highway. But mine is a track car. Anyway, the old ones were so shot that they had a lot of play in them. Park the car and put it in neutral on level ground. Move car back and forth to make sure there is no tension on joints. Get under car and try to wiggle the shaft near each joint. They should have no slop in them except for the axial degree of freedom. The things are made to telescope and bend at the joint. But they should not permit any movement in the transverse direction - ie with the shaft parallel to ground, there should be no play forward, backward, up or down or any transverse direction such as that.

If you hear the clicking sound when the car free wheels, you might be able to isolate that with the rear off the ground.