Have you change your master cylinder?

 

Yes.. with a used one I took apart and cleaned.

 

Here is my situation, similar to yours.

I had an Exedy Stage 1 for over 20k on the car with a RacingBeat light aluminum flywheel. No issues whatsoever for 20k including some drag racing, autox and road courses. Last week at Sebring my clutch failed in the middle of the road course session. I managed to make it back home (60 miles away). When I removed the clutch I noticed that the clutch disc surface on the flywheel side was gone all the way to the rivets. The flywheel side of the clutch disk was fine. I also stated noticing that it was a bit harsh to shift into 4th gear under hard acceleration about 2k before the day the clutch failed.

I figured that the pressure plate went bad so I ordered and installed an Exedy Stage 1HD. After installing the clutch/transmission back on the car I got the following problem.

1. The car will not go into gear with the engine running.
2. If I start the car in gear, it will start eventually but it will start rolling kinda like if the clutch is just barely touching the flywheel. Eventually there is noticeable burning clutch smell.

I bled the fluid so many times over several days with no results. I use ATE super blue fluid. Like you I have checked the clutch travel play and I even put a longer slave to clutch fork rod (about ¼ inch longer) and the problem remains.

I measured the distance that the clutch fork travels and I got about ½ inch regardless if I use the oem slave rod or the ¼ longer rod.

I pulled the clutch master and slave to pressure/leak test and bleed any possible air bubbles. After reinstall I bled again making sure the bleeder screw was loosen just enough to let the fluid out to a connected hose to eliminate any possibilities of getting air back into the slave.

I removed the transmission and clutch. Checked and rechecked. Put everything back and no luck. This is not the first time I removed my transmission and changed the clutch plus another time on a friend’s car. But it is the first time I have problems with it.

 

Does sound very similar to my situation.
With everything I did, I would say the slave cylinder is the likely suspect.
Especially since its a known issue and has a TSB out for it:
http://www.finishlineperformance.com...4-06-1641a.pdf

Like I mentioned... since I cut a few slits in the SC boot, I have yet to experience a problem where I couldn't get into gear.
Since my car runs fine right now, I'll likely wait to buy a new one.
But if you end up purchasing one, let me know what your results are.

 

I tried without the boot and same thing happens.

I forgot to mention that my clutch feels spongy and it doesn’t really feel hard until halfway thru the floor. Fells like if there is air in the line but trust me there is not.

The only thing that comes to mind is that there is an internal leak on the clutch master or slave that does not allow enough pressure to build since the new Stage 1 HD is stiffer than the Stage 1. Maybe that is what made it difficult to shift into 4th as I pointed out earlier.

The clutch bracket is fine plus I have the mazsport reinforce bracket too and I also have a RacingBeat steel clutch line.

I just ordered a new clutch master and slave in order to eliminate that possibilities since my car is an 2004 model.

Any other ideas/suggestions in the meantime until the parts arrive?

 

Do you have a similar issue where you have excessive pedal free play when you first start the car, but after roughly 5min the free-play decreases and you're then able to get into gear?
Once the car was "warmed-up" I had no pedal free-play.
This is what I encountered prior to cutting those slits.

Also, have you adjusted the pedal's free-play (1/8-1/4")?
What is the pedal stroke distance from the pedal pad?
Should be roughly 5" or at least even with the brake pedal.

 

Yes, even with the brake pedal.

Also, no leaks from the master or slave.

 

Another possibility is that the oem clutch master/slave combo does not have the ability to put enough force (before master clutch seal blow by) since this is an Exedy Stage1 HD and does take more pressure to disengage the clutch.

 

I was hoping to hear that. The new clutch mater and slave we behere tomorow afternoon and on the car in he evening.

I'll let you know of the outcome tomorow night.

 

geauga lake huh jon? my dad grew up in geauga county. my grandma lives in cuyahoga falls now.

 

That's cool... I used to live in Cuyahoga Falls right on Portage Trail.
Nice city to live in being so close to everything (including Blossom Music Center).

 

New clutch master and slave installed yesterday.

Same problem.

I contacted Exedy and they told me to return the Stage1HD for examination but they still believe that my problem is hydraulic related.
Seriously, give me a break please. New clutch master/slave, stainless steel braded line, ATE brake fluid, transmission pulled last night for the fourth time to recheck everything, clutch pedal welds good, mazsport clutch reinforcement bracket on, clutch pedal travel/play within specs and not the first ever RX8 clutch I have installed. But the first I had problems with, period.

I’m going back to a Stage1 since I can’t find any reviews for the HD nor any shop that has installed one.

Now I’m at the mercy of Exedy to tell me if the clutch is defective for money refund.

 

New Exedy Stage 1 went in today and the car is rolling again. Now is time to send back the defective Stage 1HD for refund.

Will post pictures tomorrow of possible indication of manufacture defect of the pressure plate.

 

this has been an issue going on months now and they still have no answer? Im up for an engine replacement in 20K miles and I would like to see how this plays out since I will install a new clutch in the new engine.

 

Take a look at the defective Exedy Stage 1HD pressure plate/clutch disk on the (right) and the new replacement Exedy Stage 1 pressure plate/clutch disk on the (left). The dimensions and configuration of both models should be the same except for the clamping power. However, notice the center of the pressure plates fingers. ?????? Any idea(s) why the difference?

 

The Stage1 HD pressure plate is 13.5 mm thick and the Stage1 is 13 mm thick.

Both clutch discs are the same.

 

Damn, thats a very thick clutch, are you sure you dont mean millimeters ?

 

Good eye, fixed.

 

Interesting...
I just measured the thickness of my disc with my digital caliper and got 8.3-8.4mm.
And there is a 3mm distance from the rivets to the top of the disc.
I too have the Exedy Stage1 HD kit.
Here is a pic:

 

Sorry again. The 13.5/13mm measurement I posted earlier are for the thickness of the pressure plate. Both clutch disks are the same thickness.

 

I was starting to do a search on just this subject when I saw this post. In my situation my 2007 has a stock clutch and original cluthc hydraulics with 80,000 miles. About 3 months ago I noticed my clutch had a loose pedal on the top 1/4 pedal stroke on startup. If I pumped the pedal a few times it would harden up. It firmed up when warmed up also, although I thought I noticed the gear changes were a little more clunky than before. The first thought I had was that the last time I bled the brakes for a trackday I inadvertenly let the master cylinder get too low which necessitated an extra brake rebleeding. I assumed I might also have gotten air into the clutch causing this problem so I bled the clutch. The problem remained. I have been driving this around for a couple of months wondering what I should do, clutch master cylinder, slave cylinder, both or what.

As the original poster noted it seems odd that it is related to engine temperature. I also use ATE Super Blue, is this stuff hard on clutch seals? I've used it on my Acura but it had a separate clutch hydraulic system. I've been using it in the RX8 for 50,000 miles, I would have thought it would have surfaced earlier.

On a related note, it was a pain to bleed the clutch slave cylinder, I can't imagine how I'm going to get at it to replace it if that's necessary, any hints? I was going to ask if it was more likely the master cylinder or the slave but this seems more complex than I originally figured.

 

Sometimes its just best to replace them both.
Its like ignition coils... one fails, you might as well change them all because its only time before the others might go.

I've never used ATE fluid, I've been using Redline, so I wouldn't worry about the type of fluid.
Plus... many people here use ATE with no ill effects.

I made a post in another thread covering the basics:
https://www.rx8club.com/showpost.php...92&postcount=3

As I noted earlier... the most noticeable change, for me, was the slave cylinder.
But I can't guarantee this would be the most likely culprit for everyone.

 

Here is what I got from the Exedy tech.

"The HD version is thicker to support the heavier clamp load. If not the cover deflection will be greater and can cause pressure plate lift issues. The diaphragm fingers are going to appear different as the HD goes through a different quenching process after the heat treatment."

I should have an answer from them regarding the clutch once they get it in a week or so.

 

Hi. I am from turkey and riding a 2008 RX8. I have the same problem. But after driving or waiting for 5-10 minutes the problem ends.

I went to service and they said the upper and lower clutch centrals fault and need to be changed. But after change the problem remained. What can ı do?

 

Has anyone solved this issue yet ? I'm having the same problems. I've installed exedy stage 1hd with exedy lightened flywheel.now I couldn't get into gear in the morning until the car warms ups.

I've changed the clutch master, slave, fork but the stupid problem still persists. Even the garages is scratching their head now.

Really contemplating changing back to oem now.