Clutch Problems After Two Step Launch

[VB-]

jzz30/r154, just put a new clutch in it last week. was an 'extreme' clutch with lightweight cromoly flywheel. direct clutch rebuild with carbonic plates and increased clamping pressure. was setting up the two step, but had it all pretty tame. did one launch at 3000rpm, one at 3500, and two at 4000, very little slipping of the clutch though, (first 3 attempts bogged down, last one was smooth but nothing too agressive) and there was probly 5 mins of very sedate driving between each test launch. on the last one, i went for the clutch and couldnt grab second, clutch would not dissengage.

fair enough, so we went and got a bottle of fluid and bled the thing for an hour, can get it to dissengage now... sometimes. its random, goes good, then shit again, bled it heaps already. thats one problem.

problem two, the c*nt is realllllyyyy f*cking noisy now, especially in reverse. makes a hell grinding noise, and rattles like a twin plate when dissengaged

did i overheat it and weld it to the flywheel? (heard of this problemon high hp supras in the US, not sure if 'carbonic' can be welded to chromoly) when clutches 'weld' them selves to flywheels, do they normally break off themselves when they cool down? why has it gone hell noisy all of a sudden?

thanks, and happy new year guys

Ben

[Simon-S14]

sad to say but thats a common problem with extreme clutches.. however its usually the brassbuttons that do it not the carbotics. either way i have a nice pile of failed extreme clutches sitting in my shed from various customers that tell another story.

[VB-]

thats the thing, while it was in the last car (current owners brother) it never had an issue. we pulled it out of his brothers car and i said its low and told him to get it rebuilt, and being that the current owner is chasing more power, we sent it to direct clutch for a rebuild, and it was them that rebuilt it with the carbonetic pads...

been driving it more today, it had a serious twin plate rattle (its only a single plate clutch though) which has since subsided, engaging issue is semi-sorted and livable. only problem is the grinding and biting now.

what actually does this simon? did i overheat it and sieze it to the flywheel?

[Simon-S14]

yeah its very possible.. but the rattle and the grinding could be indicators that the springs have broken or the holders for the springs have broken. this is the 2nd most common thing to see.

heres a pic for reference

[VB-]

yeah i took a good look over it before i put it in, springs actually seemed to be pretty secure in there, was worried they may have fallen out now tho. it does explain the biting and rattle although now the rattle has mostly gone away, its more of a grinding noise now, although even that has improved vastly with more driving. just gonna keep driving it for a bit and see what happens

thanks for the help

[SLDN-31]

my r33 gtst just did this about 2-3 hours away exact same problem i have a extreme button in it now im looking for a new clutch, I cant to get it to dis engage at all but.

[VB-]

is it definately seized to the flywheel and not a hydraulic problem? put it in first, foot on clutch, and rock the car back and forward. should break it free. or put it in 4th, clutch in and just smash it on the starter a few times lol

[Simon-S14]

well to see if its hydraulic of not just watch the slave push the clutch fork while a friend pushes clutch peddle in and out. if its moving its full travel then its 100% the clutch.

[tricstar]

is it definately seized to the flywheel and not a hydraulic problem? put it in first, foot on clutch, and rock the car back and forward. should break it free. or put it in 4th, clutch in and just smash it on the starter a few times lol

this happened to me a dozen times with an extreme clutch welded clutch plate to flywheel, push it out onto the street, start it in first (it will obviously jump forward and go but it will start) put your foot on the clutch take it up into the boost zone and nail it.. as it comes on boost it will break free, worked every time for me.. always leaves a bit of ruff stuff on the flywheel but that smooths out after a short drive with a couple quiet take offs slipping the clutch a little. when I took the out it had chunks missing from the carbonic pads obviously broken off from welding. good luck with clutch