Suspect Failed Clutch Master

[iruvyouskyrine]

Hi all.

R32 gts-t.

R33 Gts-t clutch master cylinder

R34 GT-T clutch slave cylinder

NPC clutch.

Have bled the clutch multiple times but it doesn't seem to get full disengagement. I am unable to change gears very easily when the car is turned off. With the car idling up on jackstands it takes noticeable effort to put the car into gear witch my foot on the clutch fully depressed.

When it selects a gear the wheels start turning at the appropriate speed and you can feel that the clutch is not fully disengaged as even pushing against the the gear without selecting it the wheels start to turn.

I think this means a dodgy master cylinder correct? I bought a second hand one from an R33 and bled it up, there is definitely movement at the slave as you can see it move the fork maybe an inch or so but not enough to disengage the clutch.

Just wanting to confirm it is the master?

Thanks

[boostn0199]

If your looking at the slave and it doesnt look like its pushing the fork enough then yeah its either your master or slave, but Im assuming your slave is new since you only mentioned the master was 2nd hand? Have you played around with the rod adjusment on the master?

[89CAL]

Did you bleed the master then the slave? I think if you still have the standard loop line (which I think is used to cool the oil for some crazy reason) down at the slave then there is a block there with a bleed nipple also

At that stage it shouldnt matter but I would still bleed along the system just to be sure. Master ----> Line -----> Slave

I could be wrong about that loop line or you may not have it fitted, but have a look anyway

[criptik]

Hi new to sau so not sure if I can ask question here or start a new thread. So I apologise in advance if I'm wrong.

I am also having a clutch problem. I drove the car down the shops today heard a small noise like something broke and finding a gear after tht became progressivEly harder after that to the point where I can not select a gear. I eventually limped home I noticed the master cylinder resovoir was completely full of fluid. When previously fluid level was normal. Could this be also a master cylinder failure?

Clutch had seemed normal till then accept it was kinda squeaky.

[r34unit]

I had the same issue when i first installed my clutch. i adjusted the pedal and it selected gears fine.

[iruvyouskyrine]

I think my issue lies in trying to use a 33 clutch master with 34 pull type slave. No matter what I seem to do adjustment wise it just does not exert enough pressure on the slave to fully disengage the clutch.

Anyone successfully used a R33 master and 34 slave? Or can anyone else recommend something that has more pressure (I guess this is related to the bore size?) and still is short like the 33 item as I have a greddy forward facing plenum so need something nice and short.

Surely there is plenty of people out there with R33 masters in R32's?

[89CAL]

Hi new to sau so not sure if I can ask question here or start a new thread. So I apologise in advance if I'm wrong.

I am also having a clutch problem. I drove the car down the shops today heard a small noise like something broke and finding a gear after tht became progressivEly harder after that to the point where I can not select a gear. I eventually limped home I noticed the master cylinder resovoir was completely full of fluid. When previously fluid level was normal. Could this be also a master cylinder failure?

Clutch had seemed normal till then accept it was kinda squeaky.

You may have broken the pivot ball or the pedal bracket. I believe these are the 2 most common problems in R33's

Edited September 13, 2014 by 89CAL

[criptik]

You may have broken the pivot ball or the pedal bracket. I believe these are the 2 most common problems in R33's

Not to sure about the pivot ball. I have broken one before probably 12 years ago in my s13 and completely different symptom. .. I also looked at the pedal bracket and all seemed ok there too. Only thing different is the reservoir is full to the top of brake fluid when previously it was in the normal range.

[SargeRX8]

When my clutch master failed it produced noise before it eventually collapsed on it self and i could only get home in one gear.

The system is a pain in the arse. The whole loop is redundant. If you can get.your hands on a braided line id eliminate the entire loop and go straight to the slave. It would help you ensure you've bled correctly .

[criptik]

When my clutch master failed it produced noise before it eventually collapsed on it self and i could only get home in one gear.

The system is a pain in the arse. The whole loop is redundant. If you can get.your hands on a braided line id eliminate the entire loop and go straight to the slave. It would help you ensure you've bled correctly .

There was some noise previously was a profound squeak and then a clunk of sorts. It then got worse. Pedal still has pressure behind it it just doesn't engage clutch properly to allow me to select a gear or change gears.

[SargeRX8]

The squeak is usually a sign of the cylinder not sealing properly or a worn spring. In my unit the spring snapped and the piston inside wasn't sealed causing the clutch to semi disengage and the excess fluid in the system to backwash into the reservoir.

[iruvyouskyrine]

Should mention I have a braided line straight from master to Slavs, so no issues there.

[89CAL]

OK.

So if you are confident that the system has been bled 100%, have checked for leaks then I think you need to grab a second person, get under the car and watch the slave cylinder to see what it is doing. If it looks like it is travelling a good distance (I think the throw is about 2cm? But someone correct me if I'm wrong, this is an educated guess)

If the slave is travelling the distance fine, then it may be a problem around the clutch itself. If the travel is not so good then it can only be slave, master or clutch pedal (adjustment, bracket etc)

If it were me, thats where I'd start

[iruvyouskyrine]

Yep have done this. It looks like it's moving it a good distance (around an inch) but it still won't disengage. It is a pull type clutch and the equivalent of the throw out bearing engaged properly on the fingers of the clutch cover.

Have tried 2x R33 masters now and both have the same issue. Also the shank on the bolt that connects to the clutch pedal on the R32 master is longer than the R33 one. So i put the 32 one on the 33 and tried that hoping it would exert more pressure on the slave, but even this didn't work.

Might just have to shell out the $140 for an R34 master

[89CAL]

Wait wait. You say the slave is moving a a good distance, and an Inch sounds about right. But you are still looking at the master?

If the slave is moving that far, it sounds like you have a problem AFTER the slave. Maybe you are hoping not, because pulling the box off is a big job, but I think you are wasting your time with the master at this point. You need to look inside at the clutch/fork/throwout bearing etc. You might be able to peel the boot away enough to have a look inside.

[iruvyouskyrine]

I understand what you are saying but it requires lots of effort to try and move the clutch fork, and I heard it engage on the fingers of the clutch cover. I will try and have a look but I really think that everything inside the clutch is fine, just a gut feeling.

Even though the slave is moving it feels like I have replaced the pedal with a wet fish, that's about how much feel the pedal has.

[scotty nm35]

I had the same issue when i first installed my clutch. i adjusted the pedal and it selected gears fine.

If the master doesn't return to the correct point in it's stroke it will cause all sorts of problems. I agree, adjusting the pedal is where i would start. I have had many head scratching moments caused by this.

Can you look inside the bellhousing and check the thrust bearing?

[elohim_imanu]

On 17/09/2014 at 11:31 AM, iruvyouskyrine said:

I understand what you are saying but it requires lots of effort to try and move the clutch fork, and I heard it engage on the fingers of the clutch cover. I will try and have a look but I really think that everything inside the clutch is fine, just a gut feeling.

Even though the slave is moving it feels like I have replaced the pedal with a wet fish, that's about how much feel the pedal has.

Did you get this sorted? I am in the same position. R34 bigbox with a pull clutch and a R33 master. Pedal basically drops to the almost the floor then starts working. Does not return under its own power.

This is a new build as such, conversion from auto. I am pretty sure I have bleed the master and slave, at least I can not get any more air out.

Edited June 27, 2021 by elohim_imanu

[iruvyouskyrine]

Yes, RB30 crank is like ~3mm longer than RB25. This caused the tube that the throw out bearing slides on to physically push the centre of the clutch disk into the flywheel. 

Which basically means that i was never able to disengage the clutch.

Trimmed 5mm from the end of the tube and never had an issue again