I am having an extremely unusual problem with my transmission, and wanted to know if anyone of you could provide some insight, or help.

Brat Motorsports Installed a McLeod Performance Clutch, and PP a few months ago on my 94 Z28, and it has worked great since.
However about 2 weeks ago, I was sitting at a light and accidently droped the clutch not realizing the car was in first gear (from an idle). The Car nearly stalled, but I pushed the clutch back in quick enough to where it didn't. Afterward I had trouble getting the car into gear.
Later that night, everything worked fine again, but the next morning once again it was hard to get the car into each gear, even with the clutch pedal pushed to the floor. Later that day it got to the point where I couldn't put it in gear at all (exept when rev matching). To get the car moving from a stop, I had to turn it off, put it in gear, and start it (and it would inch foward with the clutch on the floor).
So Brat Motorsports put in a new clutch Master and Slave cyl for me. (Master Cyl first, and the first they thought was defective, so they got another master cyl, and also replaced the slave cyl) After this they gave it an extensive test drive, and said it was fine.
I drove the car home. It drove great for about 25 miles, untill I was about to get off the highway, and then it wouldn't go into gear any longer (once again).
At any rate I managed to get it home, but the next morning I went out to try it, and once again it goes into gear just fine...Later that night I tried again, and its still fine.
I am scared to drive the car in traffic, because I dont know if/when it will fail again.

Sorry for the long winded story, but we are struggling to find a valid answere for the problem. Sometimes it works, sometimes it doesn't. We think perhaps it is somewhat heat related, but I drove it for several months with the stock Master cyl, and a new slave cyl (that I replaced myself) and it never had any problems.

We were wondering still if perhaps the McLeod pressure plate has more spring than the stock PP and is too much for the stock (plastic) Slave Cyl to handle?
When I push the clutch, we can see the slave cyl actually bow out about .030".

I wanted to remind anythat dont know since its a 94 it is non adjustable, and it has a plastic slave cyl, with no bleeder valve.

Any help, or experienced advice is greatly apreciated.
Thanks,
Adam

 

2 days and no reply's...

Ok, perhaps no one knows exactly what the problem is, but does anyone have any suggestions?

 

This is getting annoying...
It has to be something. Someone somewhere has to be experienced enough to know a possibility.

BTW: I drove it back to Brat yesterday. Once again once I started it it went into gear just fine. I figured it would work good for at least 10 min, but it only lasted for maybe 3-4 shifts, and then I couldnt get it in gear any more without rev matching.

So I doubt its boiling break fluid or something...

We were still thinking of trying DOT5 fluid. Although rick says he will have to completely flush the system (take the master cyl out, and everything) before puting any type of synthetic (DOT 5) fluid in.

 

I would look at ATE superblue brake fluid before dealing with dot5. Try www.ogracing.com. It has one of thei highest wet boiling points of any available fluid and is $9.99 a liter.

My thoughts.

 

Thanks for the info...
but like I said I doubt it is boiling, because the last time I drove it, the problem started happening almost instantly.

The vairiance period suggests that the brake fluid might be part of the problem, but we are thinking that it is a bent fork, and that initially it is only disengaging by a small amount (like 1mm) and then once the problem starts it is only touching a small bit, but its enough where I cant get it into gear.

However I would be willing to try this blue stuff.
Is it synthetic though? I was told if I convert to any type of synthetic brake fluid I will have to have the master/slave cyl removed again and cleaned completely of brake fluid.

Thanks again, any info is helpfull.
As it stands right now, it looks like the tranny is gonna have to come out of the car (again).

 

Nope, it's not synthetic. It is high temp Dot 4 and it is dyed blue. Nothing fancy, but it works great. You won't have to flush anything and it is compatible with regular brake fluid.

I know you said you didn't think it was fluid, but you mentioned changing it so I figured I mention the best fluid (for less than $30 a liter) I've found.

 

Thanks for the info man.
I think Coletti Motorsports has it on the shelf.
I was at an Auto-x yacking about different stuff, and someone mentioned that superblue, and said coletti had it, so I think I will try them...