How to check the pressure plate to see if it's still okay?

[930cab89]

I'm dropping the engine in order to change the steam seals and would like to inspect my clutch at the same time.
As for the disk, I think that I can simply measure it's thickness to see if it's still usable (by the way, what it the minimum thickness for a 930 1989 G50 clutch disk?), but I'm not sure about how to check the pressure plate apart from looking for some unusable wear.

[930cab89]

I wanted to say unusual wear on the pressure plate.

[Trackrash]

I am in the same situation. However, I am more interested in determining how to check the clutch spring. How do you tell if the clutch spring is even and still has adequate clamping force?

[racing97]

If you have access to a scale and a press from contact with the spring move the press downward approx .250 do not over travel the fingers must always be "proud". Take the scale measurement and multiply it times the ratio of the leverage (usuallu) 4 to 1 or so.
This will give you the clamping force and offer you a comparsion with a new unit.
regards

[T77911S]

if you see any blue "hot spots", get a new one. check the flywheel for the same

[911pcars]

Originally Posted by Trackrash

I am in the same situation. However, I am more interested in determining how to check the clutch spring. How do you tell if the clutch spring is even and still has adequate clamping force?

Here's an old school procedure that should work w/o removing the pressure plate. Confirm the clutch cable is adjusted properly before trying this. It goes something like this:

Drive the vehicle at approx. 15-25 mph. Shift into 3rd gear with the clutch disengaged (pedal depressed). Rev the engine to 4000 rpm, then pop the clutch. If the pressure plate is in good condition, the clutch will engage and the car will try to jump forward. The engine may even bog down a bit. PP confirmed good. Don't repeat too often. It's hard on the components.

However, if the engine speed momentarily rises as the clutch tries to engage w/o any significant effect on the vehicle, then the PP is slipping.

Hope this helps.

Sherwood

[Trackrash]

Sherwood, thanks, but maybe I need to be a little more specific. The clutch in my car seems to operate just fine. No slippage, even when shifted hard into third, and no shuttering on start-up.

My concern is I noticed recently that when I push the pedal to the floor and as I am letting it up I notice some roughness or possibly I'm feeling a slight vibration in the pedal. Kind of hard to explain except it feels like there is some binding and there is not a smooth operation felt in the pedal.

At first I though there was something binding like the release arm lost its lubrication, or maybe the cable was binding.
However, it does not happen when the motor is off.

I'll be dropping the motor soon and will be looking closely at the clutch. Any advice would be appreciated.

[Por_sha911]

Originally Posted by Trackrash

when I push the pedal to the floor and as I am letting it up I notice some roughness or possibly I'm feeling a slight vibration in the pedal. Kind of hard to explain except it feels like there is some binding and there is not a smooth operation felt in the pedal.

My first thought was your release fork needs hi temp/waterproof grease.

At first I though there was something binding like the release arm lost its lubrication, or maybe the cable was binding. However, it does not happen when the motor is off.

Well, that ruins a perfectly good answer (unless someone else can explain it).

[911pcars]

Originally Posted by Trackrash

Sherwood, thanks, but maybe I need to be a little more specific. The clutch in my car seems to operate just fine. No slippage, even when shifted hard into third, and no shuttering on start-up.

My concern is I noticed recently that when I push the pedal to the floor and as I am letting it up I notice some roughness or possibly I'm feeling a slight vibration in the pedal. Kind of hard to explain except it feels like there is some binding and there is not a smooth operation felt in the pedal.

At first I though there was something binding like the release arm lost its lubrication, or maybe the cable was binding.
However, it does not happen when the motor is off.

I'll be dropping the motor soon and will be looking closely at the clutch. Any advice would be appreciated.

Could be the clutch cable is starting to unravel. Is it original? A worn throwout bearing usually generates a noise whenever depressing the pedal. If the pedal box needs lube, you should hear it there.

Sherwood