SAM DACOSTA

Greetings,

I'm in need of your assistance. Today I was getting my 964 ready for Auto X tomorrow morning and in the process I had the rear of the car jacked up to access my exhaust system. After finishing my preparation (tires, tightening of exhaust bolts, etc.) and bringing the car down off jack stands, I noticed the clutch pedal dropped inside the car by almost 6" (almost to the floor board) and now I have a clutch issue. I have a relatively new clutch (6,000 miles) so it's not a bad clutch issue and I never had any issues prior to jacking up the rear of the car. I have no idea where to even start looking into this issue. Please comment and I appreciate all responses and thoughts....

Coincidence, or what is happening, or has happened?

Boeing 717

I would bleed it first and see if that solves the problem.

ian89C4

Did you use the frame jack point or did you use either the engine case or the transmission to jack it up? if you used the trans, perhaps you accidentally nocked a fluid line or something......a very weird problem.

Indycam

If you grab the pedal with your hand and move it up and down , what do you feel ?
Have you had an eyeball on the roll pin ?

SAM DACOSTA

Thanks for the response. The reason for bleeding (per my understanding) would be because of air in the system. How would that have happened as I never pulled anything related at all? It's now after 7pm on the West Coast and I cannot get any fluid right now, so that will have to wait until tomorrow. I'll respond to you after I've finished bleeding the system.

SAM DACOSTA

I used the engine case to jack the rear up. I've routinely used that as a jacking point and never had any related issues. I was also cleaning the engine and transmission cases and surrounding areas since it was accessible, do you think I knocked something loose.

Now I do have a clutch but it's only a 3" travel and the pedal now sits 6" below the brake pedal...

SAM DACOSTA

I'm going back to the garage to do exactly that and I'll respond after. Now regarding the 'roll pin' i have no idea what your talking about, so please elaborate further. Sorry for my lack of knowledge regarding 'roll pin' or terminology.

SAM DACOSTA

So I go back to the garage and decide to drive the car around the block, just to see if maybe the fluid pressure would miraculously just pickup but it did not. The car drove without grinding any gears but it only had a 2" to 3" travel.

Then I did exactly what you asked and grabbed the pedal and moved it up and down and it immediately came back to the original height and I now have full clutch travel again. WTF just happened? Excuse my profanity but it does not make any sense at all. I have clutch again, with full travel. I am happy for that but would love an explanation as to the why's so I can either prevent it from happening again or just for knowledge....

Thanks for the responses and as always, 'Rennlist' to the rescue...

Indycam

The clutch master cylinder might not have the best of piston seals .
If the seal leaks maybe the pedal drops ?

Or may be the roll pin has gone funny ?
Clutch Pedal Roll Pin Failure (or, the clutch ain't dead yet!)
https://rennlist.com/forums/964-foru...-dead-yet.html

SAM DACOSTA

I can agree the that theory but does piston seals just go all of a sudden without any warning? Or, is this the warning and it was just a coincidence with jacking up the car?

Indycam

You were expecting a postcard or something ?
Sorry .
Things go bad without any warning sometimes .
If I had a buck for every time someone has said , "It was just working !"

Now what you want to do is find what part is being funny .

SAM DACOSTA

Thanks for the information on the 'roll pin.' It seems like this is another 964 related issue. I'm going to inspect mine next weekend as a precautionary measure because maybe this is what's happening...

Indycam

Do please have a look see .
But if the symptom comes back again , I think you are looking at a clutch master cylinder replacement .

You didn't find any brake fluid on the ground under the clutch slave did you ?

SAM DACOSTA

No there was no brake fluid present anywhere. The clutch master cylinder will also be investigated per your advice. I appreciate your input always...

jeff91C2T

Saw this and thought I'd mention that this happened to me (ie...roll pin failure). I had chased my hanging clutch from the slave to the master to the line...all replaced. Only to find out it was a .99 roll pin. Go figure...at least everything is new now.

The down side to the roll pin inspection is you have to pull the pedal assembly out. Not that it's all that hard just takes some time. The clutch pedal arm slides on to a shaft in the assembly. The roll pin locks the pedal arm to the shaft. Perhaps if you pull the wooden cover and push down on the pedal and watch for the relative motion between the two you can see if this could be the problem.