Got my car back from the shop... with TO bearing noise.

[dougcl]

The car was in for an oil change/valve adjust. The clutch, TO bearing and PP have about 15K on them. No problems up to this point. When I picked up the car, the TO was making racket. The sound was distinct and alarming. How could this happen? On a hunch, I figured some over-zealous mechanic decided to torque down my clutch cable adjustment while he was under the car. They swear that they didn't touch the clutch. I backed it off and the sound has diminished to the point of being negligible (still a sound though where there was none before). Has this happened to anyone else? Should I avoid this shop in the future, or is this the sort of thing that happens?

Doug
75 911S

[marcesq]

Doug:

Was the clutch fork replaced at the same time as the clutch, etc?
If not it is possible that groves have worn on the fork ends allowing more of the fork to come in contact with the TOB, and thus more noise.

FWIW.

[Wayne 962]

Probably not related - the sound might have been there before, but you never noticed it?

-Wayne

[dougcl]

Nope, distinct and loud. The kind of sound that says: fix me now.

It's the most convenient independent P-car shop for me, but I'm thinking maybe the trouble of going elsewhere form now on is worth it. I just don't know if I'm being a bad customer or they have a loose cannon mechanic. Seems to me this sort of thing should not happen.

And no, the clutch fork was not replaced.

-Doug

[marcesq]

My vote would be:

1. Improper clutch adjustment (free play adj on clutch arm)

2. Clutch fork worn.

3. Bushings on fork shaft or shaft worn.

4. Defective TOB.

The bad news, of course, is that the engine has to come out to check all but #1.

[dougcl]

Number 1 is the only one consistent with the sudden failure mode. The rest won't come on suddenly (am I mistaken in this?). In which case the shop is not playing straight (or someone there isn't) and I should avoid them in the future.

Doug
75 911S

[john walker's workshop]

throwout bearings are pretty tough, and a tight adjustment would not generally make them noisy right away, unless they were on their way out anyway. i've backed off a lot of them that were running tight for who knows how long with no apparent noise. sitting at a light with the clutch in, and revving the engine really high for long periods of time is one way they can be damaged.