PCA SDR

Perhaps some of you will remember that I blew the old rubber clutch disk in our 944 Cab at the March 8th Autocross event. The blowing of that clutch was caused, in retrospect, by a sticky clutch peddle that hung at the floor for a moment before popping up durning a downshift into a fast corner.

To replace the clutch, I ordered the sachs clutch "kit" from Pelican Parts which includes bearings, bolts, etc. for a complete replacement of all the pertinent parts. When I got it running and bled the best I could I found that the clutch peddle was sticking in the down postion when pressed to the floor.

I took it to a local guy to have it back bled under pressure but he delivered the car back to me with no change.

I decided at that point to take it into Black Forest which normally does my work. They did a standard fluids check and replacement, bled and adjusted the clutch, and did a detailing, returning the car to me a week ago Friday afternoon.

I got about five miles down 163 bound for a meeting in Spring Valley before I noticed that the clutch peddle was again staying on the floor when I shifted. This was augmented by a new problem that the car engine would begin to die at certain points (unknown why, at that time) along the freeway. I found that if I turned off all electrics that it seemed to run fine and I drove to Spring Valley and later home.

This past Wednesday I returned to car to Black Forest. I gave a very detailed description of the symptoms on both the clutch and this new "dying" problem. I had discovered that the dying seemed to be related to having the AC on (the temp gauge would begin to wander, heading up towards the red ... if/when it reached the red the car would simply die ... no smell or other symptoms of overheat were apparent). The car stayed in two days with replacement of all clutch hydraulics, and a fairly hefty ($ wise) relay.

When I picked up the car one hour ago I made it about three miles down 163 before the clutch began to be strange and sticky at the bottom. By the time I made it back to BF the temp was also beginning to spike (I died once at a light one block from the shop).

I wasn't a happy camper. The mechanic said that he was never able to get the temp to spike after the relay replacement though he never ran the car with fans or AC. He said he was never told about the AC relationship, though I do recall these items being written down when I dropped off the car.

Secondarily, he got in the car and pumped the clutch and demonstrated that this worked fine. When the car had been dropped off, I recall describing how the clutch would stick down once the car got hot AND that the engine had to be running. I simply started the car and pushed the clutch to the floor where it stayed.

I was told to bring the car back Saturday or Monday and Black Forest would look for other causes of these problems, perhaps to put it on the "electrical" tester/computer.

I now have a fair investment ($1500; 3/4 of the price of a clutch replacement) in what started out, at least in my mind, as just a clutch bleed. I am feeling caught in an open ended catch-22 where parts are just being replaced without any direct relationship to the overall symptoms that I am describing.

For me, this is just the straw that breaks the camel's back: I just can't afford this wonderful car.

You left the ground wire off the top of the bell housing or the connection is loose or dirty.
Repair that and your overheating and dying will likely end.

Clutch hydraulics are another story.

Don't give up on her quite yet.

Steve Grosekemper wrote:You left the ground wire off the top of the bell housing or the connection is loose or dirty.
Repair that and your overheating and dying will likely end.

Clutch hydraulics are another story.

Don't give up on her quite yet.

Agreed. You may be dealing with a faulty master or slave hydraulic cylinder or a bad fluid line or fluid line connector from reservoir to clutch Master Cylinder or Master Cylinder to Slave Cylinder lines in your clutch system. Keith V. and I were sucessful in attempting to replace the clutch hydraulic lines and bleed the clutch hydraulic system in "Madame President's" car (944S2) ... turned out to be a faulty clutch Master Cylinder and not the lines (although her car's lines were toast). Her car's symptoms were identical to yours: clutch pedal went down and stayed down ... engine running or off.

If you have the time and patience: take a good, small flashlight; start at the brake fluid reservoir, and follow the blue line down to the clutch M. cylinder; then follow the rubber-and-metal lines all the way to the slave cylinder cozied up in the center under the car, directly next to the starter (yup, jackstands and coverall are needed for this one). If you see any fluid leaks, carefully note/map them out and call a good garage (BF, Dieters, Mirage, etc) and tell 'em what you might have found. If you find nothing in the hydraulics, my only other guess (and it's way out there) would be the spring plate in the new clutch assembly you bought is bad, or the shaft sleeve is rubbing/binding and causing the clutch to stay disengaged ... not likely. If I were a bettin' man, I'd go with hydraulics on this.

Remember: in car care; 85% of a great service experience is proper diagnosis from the beginning. The rest is akin to highy complicated light-bulb changing. (No offense to any Technicians intended)

Good luck with it. Don't lose patience ... or the car ... yet.

Dan

Steve Grosekemper wrote:You left the ground wire off the top of the bell housing or the connection is loose or dirty.
Repair that and your overheating and dying will likely end.

Clutch hydraulics are another story.

Don't give up on her quite yet.

Ah ... haven't gotten into it yet BUT ... a quick look in this morning before running off on errands revealed a loose ground strap at the top of the bell housing (nut just started on threads).

Thanks ... will give it a try this evening!

Dan Chambers wrote:You may be dealing with a faulty master or slave hydraulic cylinder or a bad fluid line or fluid line connector from reservoir to clutch Master Cylinder or Master Cylinder to Slave Cylinder lines in your clutch system.

Thanks ... but unfortunately Black Forest replaced all of the above last week ... with no change in symptoms .
Have you and/or anyone else ever had problems with the spring that is built into the peddle mechanism???

The problem is hydraulic.
944 clutch bleeding can be very difficult and frustrating.
The hydraulic line looks like a roller coaster and loves to trap air.
There are about 3-4 techniques depending on how difficult the car is being.
I would give BF another chance to get the air out.

Dan Chambers wrote:Remember: in car care; 85% of a great service experience is proper diagnosis from the beginning. The rest is akin to highly complicated light-bulb changing. (No offense to any Technicians intended)

Good luck with it. Don't lose patience ... or the car ... yet.

Dan

None taken considering the source.
Some of us still play with cars and some still play with dirt...
So people pay you to tell them their dirt is dirty-Right?
I am sure I am over oversimplifying... (No offense to dirty dirt testers)

Dan you crack me up.

Steve Grosekemper wrote:You left the ground wire off the top of the bell housing or the connection is loose or dirty.
Repair that and your overheating and dying will likely end.

Clutch hydraulics are another story.

Don't give up on her quite yet.

Now thats a mechanic who knows his sh*t...

Steve Grosekemper wrote:The problem is hydraulic.
944 clutch bleeding can be very difficult and frustrating.
The hydraulic line looks like a roller coaster and loves to trap air.
There are about 3-4 techniques depending on how difficult the car is being.
I would give BF another chance to get the air out.

+1. I used a Power-Bleeder at 8-psi to bleed M. Pres.'s system. Without a mechanical advantage on the hydraulics (pressure from above or vacuum from below) I can't imagine how you'd bleed the clutch.

Steve Grosekemper wrote:None taken considering the source.
Some of us still play with cars and some still play with dirt...
So people pay you to tell them their dirt is dirty-Right?
I am sure I am over oversimplifying... (No offense to dirty dirt testers)

Dan you crack me up.

You are correct! It's a simple deal: no one else is dumb enough to go digging in hazardous waste infiltrated dirt ... except me. And I get paid for it. Wish I were still playing with cars ....

Dan

First ... thanks to Steve for the ground strap suggestion. Loose nut has made a great performer of the cab again. I can see that I would have save myself $600 by asking you first!

As far as bleeding the system, though ... historically:

1) it was bled by me after the clutch installation

2)it was power bled by Import Auto of Santee when my bleeding didn't work (local BMW/Porsche mechanic)

3) it was bled by Black Forest including all all replacement about ten days ago

4) it was bled by Black Forest again after ALL clutch hydrolics were replaced last Thursday-Friday

At no time have the symptoms changed (including the same "strange sticking" beginning BEFORE the clutch disk failed).

The point that I am trying to make is that this is starting to feel like "Bleeding Edge" technology (pun really intended ).

Also ... I intend no criticism of John or Mark or any of Black Forest's top experts, I suspect that they would have spotted that loose ground in short order.

Rather ... I am just feeling that the folks who are working on the car in for repeated bleedings and ever increasing parts replacements are just not finding what is wrong and I am fearful of an ever increasing cost with no resolution in sight .

So my question is ... is there anything else that could affect the peddle? There are some obscure notes on the Rennlist forum that alludes to a peddle spring problem ... what does this spring do (I am sure that Porsche put it in there for some reason) because I sure can't figure it out.

Sorry if I sound exasperated ... thanks all

Perry

So my question is ... is there anything else that could affect the peddle? There are some obscure notes on the Rennlist forum that alludes to a peddle spring problem ... what does this spring do (I am sure that Porsche put it in there for some reason) because I sure can't figure it out.

Sorry if I sound exasperated ... thanks all

Perry, I understand your frustration. Some day I'll tell you about a 2+ year (and way too many $$$) stalling problem my 944 had. Been there. Done that.

Okay, to answer your question, there is a helper spring attached to the clutch pedal that helps smooth-out the pressing motion of the pedal. It attaches way up high under the dash/footwell. This is a helper spring to "depress" the clutch, and if it went south, the pedal would probably be harder to press. Not your symptom, right? On the other hand, if that spring somehow were dislodged from its mount, or somehow wrongly placed or ... something else I can't think of .... it might possibly interfere with the normal function of the pedal, but I consider that highly unlikely.

So, here are a couple of other really odd and way-way-out-there possibilities:
- Clutch pedal mounting has failed. Pedal is being pushed into footwell by "artificial hinging" from spring tension and failed mount.
- Clutch Master Cylinder has pulled out of the firewall and failed. (Should leak if so)
- Clutch Slave Cylinder has pulled out of the mount and failed. (Should leak if so)
- Throw-out bearing armature (arm that slave cylinder rod pushes on) has failed or dislocated.
- Broken shaft/piston from pedal to clutch master cylinder
- Faulty pedal post/landing where CMC shaft meets pedal
- Cracked fittings on reservoir .. losing hydraulic capabilities (Cheap plastic that's old.)(Should leak if so.)
- Low fluid level in reservoir is leaking bubbles into system.
- Bad brakes are somehow bleeding air into clutch system (virtual impossibility)

So, as you can see, there is a miriad of potential causes. If the S2 is a Daily Driver, I guess you need to do what ever it takes to get it going. If it is a "hobby" car for pleasure/leisure, you got yourself a new, fun task at hand. I know it's frustrating ... and seems costly ... but it's part of the Porsche/Ferrari/BMW/Astin-Martin/Austin-Healey/MG Hobby Car experience.

I make it a mental challenge (like playing chess) rather than a dilema, and try to approach it with calm, intellectual reserve rather than anger and frustration. I know it's easier said than done, but it helps to approach it with a cool head. Afterall: you could be attempting to build a saiboat in your garage ... only to find you didn't plan on how to get it out!

Good luck, and keep us posted.

-DC

The clutch spring is there to assist in holding the clutch in at a stop.
It is a helper spring that only works after the pedal has been pushed more than about 25%.

The hydraulic pressure (much stronger) works against that spring pressure.
I doubt the spring is an issue.

Just take it back to BF and talk to Jeff.
There are different methods they can use for "pesky" clutch hydraulics.
I am sure they will be able to make it better again, just give them a chance to do so.

May seem like a silly question, but where the brakes bled at the same time as the clutch at each of the bleeding events? I have had what you describe happen to me after replacing some clutch hydraulics and only bleeding clutch. Took a step back, got the Clark's Garage procedure and followed it precisely. Problem went away not to return.
In short, lift back of car as high as possible.
Pressurize to 12 psi at reservoir with power bleeder (make sure there is plenty of fresh fluid in the bleeder and reservoir.
RR wheel
LR wheel
Clutch
RF wheel
LF wheel
Check/fill pressure on bleeder after every wheel
REPEAT.

had to bleed mine at different angles. On ramps with front wheels, on ramps with rear wheels, flat ground, on curb with right side, on curb with left side. it took a bit of fluid but what ever. What you describe is hydraulic and can be fixed. I had the same problem, don't pay anyone anymore money! I would check grounds and bleed the heck out of your clutch. maybe try another master cylinder and slave. they are cheap and often made to loose specs.

Perry,
While Steve is being very politically correct, and again no slight whatsoever to BF, why not take it to Steve? Sometimes a different perspective can spot issues quickly. Yes, it costs $, but who told you maintaining a P car was cheap?
why not have it done right, and save yourself the headache.

My .02