924Board.org

[Robb Northrup]

Folks:

Over the weekend, the old car (1980 NA) started producing a "clicking" sound in the rear. The frquency of the "clicks" increases as vehichle speed increases.

I'll be hitting 100K in it later this week!

My first thought is that a CV joint is failing. But all the cars I've had that used CV joints were front drive cars, and the sound of a CV joint going bad was more "grinding", especially when turning.

Any thoughts out there? When it gets warmer here this weekend, I'll raise the car to check it out. But any ideas ahead of time on what it could be would help.

Robb
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I've owned too many cars. 1980 Porsche 924 with European bumpers

[Rasta Monsta]

Get your tools together to remove the axles and, at a minimum, clean and lube your joints.

CV Grease (special moly lube from VW or Import shop)
Fresh fasteners (24, also available from VW speed shop. . .same as Type II Bus)
8mm "triple square" bit to remove fasteners
Solvent to clean joints (I use Brakleen)
Sturdy circlip pliers to remove joints from axle shafts

You may also need boots (available, guess where, VW shop).

To remove the fasteners, make sure the heads are cleaned out with a pick and then sprayed out with Brakleen. Then, tap your bit into the head with a large hammer (Did I say tap? I usually hit it fairly hard a few times). Crack all 24 before removal. Upon removal, set them out so you can keep track of which joints were inner/outer and right/left

Once they are off, clean them thoroughly and inspect races and steel balls for damage. If hardening is worn off, the joint is shot.

Once good joints are clean, mark their originally installed position and rotation with white paint. Pack them with grease, and reinstall them so they are rotating the OPPOSITE of how they came off. . .this will extend their service life.

If I forgot anything, stay tuned for additions/corrections.
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Toofah King Bad

• WeiBe (1987 924S 2.5t) - 931 S3

[joecitizennn]

Rasta gave you some good advice, but I would also make some effort to isolate the sound before resigining to a teardown. Your description makes it sound as though whatever is clicking simply does it in beat with the outer drivetrain speed. Does it click when you coast? Does it change under hard acceleration or go away at any time? Can you produce the noise with the vehicle raised and turning the wheels by hand or do you just hear it while driving? Have you looked under the vehicle to see if something nutty has happened like a scrap of wire has gotten wound around an axle? Have you checked your axle play?

[Robb Northrup]

To JoeCitizen: Here are the symptoms:

It clicks on acceleration and does somewhat on coasting. Depending on the torque load, it will go away (a little) but once I start accelerating at all, it's back.

Haven't yet gotten under the car (it's been way below freezing here until yesterday). I'll do that Friday when I take time off (and the temp is closer to 50 F!).

Regarding axle play, do I just yank at the axle? There's nothing in the Haynes manual regarding diagnosis; only removal.

If it's deffective, I'll just order another unit rather than mess with rebuilding.

Robb
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I've owned too many cars. 1980 Porsche 924 with European bumpers

[joecitizennn]

Your second description sounds very much like it could be a cv joint.

From the rear of the car push forward and backward on the axle. There should be little to no play. Note that it will slide side to side in the joints themselves as it is designed to. Some very faint play can be considered normal if the car is high mileage, but anything more than that calls for new parts. Wear occours between the cv balls and the pockets they ride in. Broken balls or a broken cage could cause a noise like you are hearing. If the noise occoured suddenly it is unlikely to be just simple cv wear. I don't know the exact noise a dry cv in one of our cars makes because i have always maintained mine, but if you are driving it dry to the point it makes noise, damage is being done anyway.

[Rasta Monsta]

FWIW, I have heard a couple clicking due to lack of lube. . .very little visible damage, and a grease job fixed them right up.
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Toofah King Bad

• WeiBe (1987 924S 2.5t) - 931 S3

[mikebola]

is there a torn CV boot? from my experience with fwd cars, if the boot is torn " the joint has become compromised by road grime and should be replaced" according to some knowledgeable people
Now I've successfully alleviated the click in a dried out cv that had a cracked boot/intermittent clicking noise and put one of those bolt together boot kits on one, but the car was sold after about 200mi. I've heard good and bad results from that approach.
I guess I'm saying that either way works, but you'll guarantee that it'll last if you replace it.
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proud owner of a 1979 924 Sebring Edition with a 931 trans that looks horrible but somehow runs...

[Robb Northrup]

Folks:

Haven't as yet gone under the car. That's for tomorrow when our store is closed and I'm off!

But interestingly, this morning the clicking was there when I drove from home, but as the temperature has risen to the upper 40s (Fahrenheit) today, as I drove home, the clicks were gone!

A thought: could it be that the noise was caused by lack of enough grease to handle the cold?

I'll check out the axle tomorrow, but I could settle everything tomorrow if it's only grease...

Robb
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I've owned too many cars. 1980 Porsche 924 with European bumpers

[Joes924Racer]

I had a inner whee bearing go out back there...not the cves and it sounded like it was being hit with a sledge hammer that was the bearing failing big time. I took my axle shafts apart then and rebuilt them with fresh lube. Its been a while. Make sure the wrench is in there all way
or you will damage the head & have to dremel it off. Cheers
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1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.