Clutch not disengagin properly

[Pyren]

Hi guys,

 

I have a problem. First of all I do have a Twin plate clitch in my r33 gtr. When pressing the clutch pedal it make some rattling noise, after reading and gathering some info this is considered as normal with those type of clutches? The bigger problem is that my gearbox sometimes gets stuck in 1st gear when im stopping with the clutch fully pressed it still wants to go forward. Also its really hard to change gears sometimes.

 

I ve done an gear box oil change and bleeded the clutch line (both damper and slave cylinder).

Nothing helped.

I would need some advice where too look at next. Could it be that my clutch pedal needs to be adjusted? (clutch feels heavy but normal and the point where it grabs is late)

Please give me some advice :)

BR

[Duncan]

Yes, it sounds like it is not disengaging fully, so bleeding the line is the place to start. It can be hard to bleed well, particularly if the long factory line (damper) is still in place. One way is to fill the master, add a small piece of hose to the slave bleed nipple and open the bleeder and let it gravity bleed for a while.

And yes, if the take up point is quite high you can adjust it at the pedal by undoing the lock nut and turning the threaded rod at the pedal to lengthen it. Keep in mind that if this is the problem it means you clutch is almost certainly totally worn, and when you replace it (shortly) you will need to adjust the pedal back up again.

There are a bunch of other reasons it might not release properly including release bearing carrier size issues, but air in the lines or worn clutch/pedal adjustment are the most likely if it has been working properly in the past.

[PLYNX]

Have you checked your clutch pedal box ? They are notorious for cracking and bending out of shape !

Had to get into the foot well with a torch to see it 

Happened to me with the twin plate I had.

[Pyren]

10 hours ago, Duncan said:

Yes, it sounds like it is not disengaging fully, so bleeding the line is the place to start. It can be hard to bleed well, particularly if the long factory line (damper) is still in place. One way is to fill the master, add a small piece of hose to the slave bleed nipple and open the bleeder and let it gravity bleed for a while.

And yes, if the take up point is quite high you can adjust it at the pedal by undoing the lock nut and turning the threaded rod at the pedal to lengthen it. Keep in mind that if this is the problem it means you clutch is almost certainly totally worn, and when you replace it (shortly) you will need to adjust the pedal back up again.

There are a bunch of other reasons it might not release properly including release bearing carrier size issues, but air in the lines or worn clutch/pedal adjustment are the most likely if it has been working properly in the past.

Thanks for the input, i am pretty sure that we managed to bleed the lines well so that point is done. If the clutch is nearly done then it is finde for me but my concern is that its not opening fully. I just want to sort that out before i do something else.

[Pyren]

9 hours ago, PLYNX said:

Have you checked your clutch pedal box ? They are notorious for cracking and bending out of shape !

Had to get into the foot well with a torch to see it 

Happened to me with the twin plate I had.

what do you mean with cracking and bending? u mean the master cylinder?

thanks

[Pyren]

9 hours ago, PLYNX said:

Have you checked your clutch pedal box ? They are notorious for cracking and bending out of shape !

Had to get into the foot well with a torch to see it 

Happened to me with the twin plate I had.

Also I dont think thats bent, the pedal feels like it should, or wouldnt i recognise it?

[Duncan]

1 hour ago, Pyren said:

Thanks for the input, i am pretty sure that we managed to bleed the lines well so that point is done. If the clutch is nearly done then it is finde for me but my concern is that its not opening fully. I just want to sort that out before i do something else.

then, adjust away!

you can see if the lines are bled properly (2 person) with one pressing the clutch and one watching the slave cylinder move. There should be less than 1cm free play on the clutch pedal before the slave starts moving. Also, while under there you can check the slave actuator rod is resting on the fork (no slack) without any pressure on the pedal

[Pyren]

15 minutes ago, Duncan said:

then, adjust away!

you can see if the lines are bled properly (2 person) with one pressing the clutch and one watching the slave cylinder move. There should be less than 1cm free play on the clutch pedal before the slave starts moving. Also, while under there you can check the slave actuator rod is resting on the fork (no slack) without any pressure on the pedal

teah we looked at it it seems to be fine, we bled the lines and changed the whole brake fluid. 

 

next step i am going to look at is too shortcut the clutch damper. maybe de piston of the damper is not sealing well. friend of mine had that problem on a Nissan Patrol. Ill give an update.

 

Thanks in advance!

[GTSBoy]

1 hour ago, Pyren said:

cracking

Cracking. As said, they are famous for it. Close inspection with bright light & mirror while someone else pushes the pedal is a good idea.

[Pyren]

8 minutes ago, GTSBoy said:

Cracking. As said, they are famous for it. Close inspection with bright light & mirror while someone else pushes the pedal is a good idea.

thanks ill have a look!