Update and more questions...

[ipaqrat]

In response to my last few posts, I got a lot of sound advice, so thanks again for that. Now, I'm back at the well...

Among all the work I had done last spring, was replacement of the alternator belt after it rather dramatically burned off its pulley. That incident was presaged by a chirps and squeals from time to time on downshifts and takeoffs from stops. I didn't know what the noise was then, of course.

NOW... I'm starting to hear little chirps and squeals again. Is there something specific I can troubleshoot (or, more likely, ask my mechanic about). Are 993's prone to this? I've read a few oblique comments about it in a few magazines (I read 911 & Porsche World, Total 911, GT and Excellence every month.)

Thanks!

[Tom W]

Are 993's prone to it - no. I'd suggest you have someone take a look at it.

[bazar01]

Has the belt tension changed on the new belt after so many miles of driving?
Probably just needs retensioning, or worst case, the pulley face is damaged, and chewing up the belt.

[ipaqrat]

I've read that 1/4 to 1/2 inch deflection is about right, but how does one make such a test? Instinctively, I'd just give it a poke about halfway between the pulleys and guess. Is there a degree of precision one must meet before one tells one's mechanic that one's belt needs adjusting?

I never thought about the pulley face - that would explain why the noise (if it's the belt) progresses. It's been somewhere between 1200 and 1600 miles. I lost count.

I have ZERO service records from this car's former life. In order to re-baseline its condition (essentially starting over), I'm taking everything to my mechanic until each subsystem has had a once over. Cheap, it ain't; seems like a worthy investment so far. Maybe one day, I'll figure out which is the business end of a wrench.

Thanks,

JD

[AFJuvat]

Also, that little tensioning monitor has a plastic wheel that will chirp and squeal when it is going bad.

0.25 - 0/33 inches of deflection is about right.

AFJ