Jump to content
The mkiv Supra Owners Club

Clutch Issue, Twisted main shaft or something else?


JamieP

Recommended Posts

Had problems with my clutch all day at suprapod, i only got a few clean runs.

 

The peddle kept getting stuck on the floor, really slow to come back up, seemed ok if i took it slow but soon as i hammered it it would get stuck down again.

 

It got worse as the day went on and i had to give up after it happening 4 times in a row.

 

Ive had something similar before and it turned out to be a twisted main shaft on the box.

 

Any other ideas as to what it could be?

 

Cheers Jamie.

Link to comment
Share on other sites

I take it you have covered the simply things like air in the system? I had similar issue on my Skyline. Once clutch was hot the pedal was getting stuck to the floor. It was air that was expanding with heat and pushing the slave back but pedal was stuck. O and worse when giving it some as the extra heat build up around the box and engine. Strange that the clutch pedal; felt normal tho when driving it sensible.

 

I have also had the same issue on a Audi. It was caused by excess clutch dust bulid up on the input shaft that was slowing the realse bearing from travelling back to position.

Link to comment
Share on other sites

Ive not touched the car yet, just looking for ideas as for what to look at before we pull the box, cheers.

 

Excuses :D just joking, Maybe air in system, needs bleading .

 

Following you home i had to lift the peddle with my foot every time i put my foot down, was getting real bad, still fine if driven slow though.

Link to comment
Share on other sites

I'm having a similar problem, when clutch is worked hard or gets hot it disappears.

I changed clutch fluid and fitted an heat shield around master cylinder.

 

When i tried bleading the clutch fluid through the system the peddle was stopped at floor level, i then decided to swap slave cylinders, new MrT one fitted, still does the same. Next step was to fit a new master cylinder.

 

Ryan did note this when he was mapping on RR, he suggested i fitted a n/a slave cylinder with more travel.

 

I'm now thinking my clutch is slipping since it was remapped with more torque and power so the dissapearing clutch is a side issue :(

 

Just got to decide which clutch system to get :rolleyes:

I've had 2 HKS twin plates and only done less than 5k miles so this time what ever i get will have to work and last.

Its not an easy solution getting a road/drag clutch a bit like suspension systems nothing really does both properly.

 

Good look with sorting your problem and keep us posted, also well done today with a 10.1 using a knackered clutch, no wondered you didn't do a 1.5/1.6 60ft time and get into the 9's :(

Link to comment
Share on other sites

Had this problem on the HKS tripple clutch i pulled out not long ago(don't know what you have) really annoying you'd be in traffic go to pull away lift your foot and nothing pedal on the floor then all of a sudden "twang" stall and you look like a numpty! Happened maybe 8 times or more but despite the clutch being supposidly new it slipped on high boost so ripped it out and installed a twin plate carbonetic and now half the travel and no issue's at all! I'm going to get the carbonetic tripple for the new engine to and leave the twin on my spare 612hp engine.

Link to comment
Share on other sites

The only hydraulic issue I can think of is a sludged up master cylinder. I would say if the pedal is not returning *AND* you have clutch slip it's probably mechanical. Seeing the grunt your car had today I think you need to look at a different gearbox and axle assembly. It needs a spool, probably a much bigger / stronger CWP and casing, and a serious gearbox, probably a Lenco or a proper drag spec auto. Awesome power, let down by traction issues and I am sure the drivetrain is glad to be asleep back in your garage, resting :)

Link to comment
Share on other sites

Thats all straight over my head Chris (fluid aside) but thanks for the input, hopefully Lee will know what you mean.

 

 

Its basically an all in one release mech which combines the slave and release bearing into one and eliminates the clutch fork.

 

The stock 6 speed uses a pull type mechanism so i dont think its a viable fix although OS Giken do a conversion kit for this.

 

http://www.rhdjapan.com/os-giken-push-pull-movement-conversion-kit-10885

Edited by Kirk (see edit history)
Link to comment
Share on other sites

Giken, for one, ditches the pull type clutch assembly and uses a conventional twin or triple plate push clutch release. They sell an adaptor kit to convert the pull of the stock mechanism to push, but pivoted arms, and bearings sliding on the nose of the gearbox input shaft tube, with external slave cylinders are from the past, concentric release is unbelievably nicer to use, especially on heavily sprung race clutches.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.