So I'm tuning into an issue with my car and just wanted to get some insight in reference to bleeding the clutch. I did the gt2 conversion on my car (full oem gt2 parts) 3 months ago. Replaced the master cylinder, gt2 slave, gt2 spring etc. bled the entire system and car felt great.

Fast forward to last week, Now I have that dropped pedal issue. It dropped about 3 inch(not exactly to the floor) So figured maybe I have air in my system so decided to hook up the motiv bleeder and perform a full flushed. Pumped it to 10-15psi and nothing came out of the slave bleed screw......then I tried to pump the pedal and the pedal is now fully on the floor, tiny bit of fluid came out but completely stopped releasing any fluid and won't bleed through. Any idea if this is a definite master cylinder issue? I'm quite mechanically incline but bare with me as it's been a learning process for me on my first 911 turbo. Any help much appreciated!

 

My guess is that residual pentosin probably ate the seals. If you don't get it all, even a trace will work the seals over time...

 

This sounds familiar.

Check out my very recent thread: https://www.6speedonline.com/forums/...ng-clutch.html

On the last page I posted a picture of what my master cylinder looked like inside. I'll bet yours has a similar failure given you can't get any fluid out with the pedal to the floor.

 

Sounds like the master is shot especially if now it won't push any fluid. This would
be the 3rd one I've heard that that went bad after conversion. It seems it's hard to remove all pentosin 1st time around.

 

On the plus side, it's not super hard to swap! I did a write-up on doing an SRM master but swapping a new master in will be much the same for you.

 

Any chemical wizards out there that can confirm the correct solvent for Pentosin?

Denatured alcohol?
Brake cleaner?
Carb cleaner?
Gasoline?
Flush with 10 gallons of DOT4?

Doing this conversion soon and would like to avoid issues.

 

all of the above!! if your doing the oem conversion all that remains is the reservoir and the line to the slave. 2-3 qts of dot 4 should do the trick. its what i used and have had zero issues