Screech when changing gear

[Targa_whaletail]

Hi all,

My 911 Carrera 3.2 1984 has had virtually no use in last 6-7 months - it's been sitting in a workshop either getting re trimmed or engine work.

Back driving it now, and when cold I'm getting a Loud screech (a bit like skidding the tyres) when letting out the clutch. This seems to go when the car is warmed up.

Car has around 125k miles. The previous owner installed a Sachs clutch kit 915.116.911.00 and clutch bolt 900.067.090.02 and a bunch of exhaust components in 2007 at 108k miles.

Any thoughts please? Will this go with use?

[Matt Monson]

Throw out bearing.

[Targa_whaletail]

Originally Posted by Matt Monson

Throw out bearing.

Thanks. Oh dear.

Does that mean a new clutch as well? I assume the engine and gearbox need to be dropped to replace the throwout bearing?

[Sooner or later]

Engine drop. New clutch not mandatory.

[Targa_whaletail]

Originally Posted by Sooner or later

Engine drop. New clutch not mandatory.

OK thanks. I see the throwout (release) bearing is about a third of the cost of a clutch kit.

However, I'm surprised this failed so fast (in miles), as it would have been in the Sachs clutch kit the previous owner had installed.


If I go "all in", and get the Sachs power clutch (al rather than steel, 1.7kg lighter), is that well regarded?

If I get the full clutch kit Pelican offers, should I also get new clevis pins (for the pedal box I guess)? I also see there is a kit of bronze bushings you can get. Is there any way of knowing if the pedal box needs a rebuild?

[Targa_whaletail]

Hmmm. Got the clutch replaced with an OEM Sachs, also the throwout bearing (as part of the kit), new flywheel, new clutch cable and assorted items.

It is still occasionally screeching when changing from 4th to 3rd to 3rd to 2nd - even a slow change - before the gear oil has warmed up. I'm running Swepco 201.

It's gone back in again as so much work was just done.

I'm really surprised it's still doing this . . any further thoughts?

[boyt911sc]

Originally Posted by Targa_whaletail

Hmmm. Got the clutch replaced with an OEM Sachs, also the throwout bearing (as part of the kit), new flywheel, new clutch cable and assorted items.

It is still occasionally screeching when changing from 4th to 3rd to 3rd to 2nd - even a slow change - before the gear oil has warmed up. I'm running Swepco 201.

It's gone back in again as so much work was just done.

I'm really surprised it's still doing this . . any further thoughts?

There was a PP member who wanted his 915 transmission rebuilt because of his shifting problems. It turned out that the owner was not familiar how to properly do the shifting. Find someone local who does a lot of track driving with 915 transmission and let him test drive the car. You might be surprised to learn something new. Good luck.

Tony

[jpnovak]

Fan belt too loose? This would make noise every time you shift gears and the fan changes speed.

[Targa_whaletail]

Originally Posted by boyt911sc

There was a PP member who wanted his 915 transmission rebuilt because of his shifting problems. It turned out that the owner was not familiar how to properly do the shifting. Find someone local who does a lot of track driving with 915 transmission and let him test drive the car. You might be surprised to learn something new. Good luck.

Tony

True - you raise an interesting point. For background, I've had the car for 2 and a half years, and it was OK until this year when the problem appeared, and then got very bad.

Gearbox was rebuilt by previous owner about 15k miles ago. Engine and transmission mounts have been replaced (about a year ago), as well as seine gateshift, new coupling, new bushings and so forth.

I have tried shifting with a pause an neutral, also giving it a blip of gas, slower clutch release at after completing the change etc. But maybe I'm missing something.

I've been told the alternator belt is a little loose, so having that looked at also.

[Targa_whaletail]

Originally Posted by jpnovak

Fan belt too loose? This would make noise every time you shift gears and the fan changes speed.

Ah ha - didn't see this when I just replied. I've been told it is a little loose.

[john walker's workshop]

If the screech is from the transmission, it usually is related to a loose guide fork for the shift rod selector finger. Pull off the plate and see.

[Targa_whaletail]

Originally Posted by john walker's workshop

If the screech is from the transmission, it usually is related to a loose guide fork for the shift rod selector finger. Pull off the plate and see.

Thank you! I'll pass this along also.