Calling all clutch bleeding experts
 

Just got back from my first tack day with a new Specialty Z Max street clutch, flywheel, csc. I also replaced my master cylinder.

the problem I am having is right after I get going in the session 2 to 3 corners or so the clutch pedal engagement goes from about mid pedal range to just off the floor, and a few times deeper into a session the pedal will come back up but, it hesitates before the spring pops it up.

Ive bled the clutch per the FSM and gravity bled it before that. During bleeding I get absolutely no air bubbles at all coming out of my bleed tube.

any idea's, tricks, suggestions?

Thanks

Crack the line open at the master cylinder. Bleed it there. You may have some air trapped there.

Well got a little hiss when I cracked it... re bled it at the master 3 or 4 times then re bled the whole system feels firmer but, I'll find out at the track tomorrow:ugh2:

What fluid you using? Do you have a SS clutch line also? I'd also recommend the Z1 external SC. I've had several issue using the best clutch fluid and equipment and due to the heat I couldn't get the gears to engage due to the heat. But that always seem to be after the cool down lap.

Motul RBF 600 and its either hardline or stainless tubing. Very similar in looks to the Z speed CSC.

same issue today at the track. It feels like after the compression stroke it back fills really slowly and as the heat builds in the session it lasts longer. After the cooldown lap it is stiff as can be though WTF?

I think Rusty might have it pegged though air in the MC.

FSM says not to presure bleed it but, not sure what else I can do. I guess I could pull it back out and bleed/fill it on the bench.

One good thing I was able to beat my best time again on the outer track.:tup:

from the sound of things you are boiling over the clutch fluid, wrap the line in some DEI heat reflective wrap, wrap your testpipes / cat's with some additional heat shielding and bleed your clutch using either Endless RF650 or OE Nissan GTR Brake fluid.

Clutch fluid boiling sounds feasible. Torque RT700 and Castrol SRF might be worth testing out for a track session.

Boiling the fluid never even occured to me because i have never had that issue with the stock setup. That does make sense though..the feedline to the tilto CSC it to short IMHO. I have a Z1 Ss line i might be able to throw in if the banjo bolt will seal around the female potion of the line conection. I have the line heat wrapped already but, more is better

it's a common misconception. Rubber does not retain or handle heat anywhere near as much as rubber does. the OE line is wrapped with some heat shielding and the OE cats have a pretty gnarly heat shield around them so it's rare to boil over the fluid on the OEM line I've personally never seen it happen. (CSC seal will rupture before that happens)

the SS line can withstand more heat and the nature of stainless steel it also retains much more heat which in turn is absorbed by the fluid. also if you have test pipes or HFC's they no longer have any of the factory shielding so that will add to the boiling over factor. temperature control is very important every time we install a SS clutch Line we make sure to wrap the lines in DEI gold reflective wrap and use a few feed of header wrap around the testpipes / hfc portion that is near the fluid to keep the clutch fluid happy.

Thanks for the input. I will add some more protection and see if that does the trick.