Boosted Performance

iTrader: (14)

Ok, so I spent about 1.5 hours messing around with this dam clutch pedal and it not returning all the way up after a shift. Did a complete fluid flush, so that is not the problem, bled it for 30 minutes…no improvement.

It stops about ¾ of the way back, and that is it. I can return it all the way by pulling it up, it then “pops” in place. I am not an expert in this area, but what is supposed to return the clutch pedal all the way back? For some reason I don’t think I am getting the full range of motion on the withdrawal lever. There is about ¾” of travel at the operating cylinder (in/out movement) when the clutch is pressed/depressed. Should there be more?

Also what is the purpose of that giant spring at the very top? The way it is engineered it does not seem to do much, it travels more up/down than in/out.

terrasmak

iTrader: (8)

There is crap built up in the master, pull the master out and disassemble, clean it. Also when you do that, just pay the $15 for the Nissan rebuild kit and replace the internals of the master.

Boosted Performance

iTrader: (14)

Just called the dealership, not a single rebuild kit in the country (Canada). I may take it out anyway and see what is going on...just frustrting when you go and try to fix a small problem and it turns in to a larger one.

I am still confused as to what returns the clutch pedal all the way back? Is it te spring inside the the master cylinder, or is it the spring behind the clutch release bearing that pushes the clutch lever back?

ZSpeedPerformance

iTrader: (71)

The master cylinders are crap, If they leak on the way back into the reservoir the clutch cannot push the pedal back up as there is no pressure any longer. The clutch pressure plate itself is what returns the pedal to the original position via fluid pressure.
3/4" travel at the end of the slave fork is normal condition for the stock set-up.

What year is your car?

Cass007

iTrader: (34)

Do you have a SS line and have you tried the Motul fluid? I had this issue with my Turbonetics kit and the above things fixed it. Is it all the time or just after driving for a while?

Boosted Performance

iTrader: (14)

It is a 2006 Z, 40k miles. Some searching tells me that many people with an 05-06 Z have issues with the clutch at about this mileage.

Cass I do not have a SS line, and the fluid is new so I am sure it should work with a complete flush even with the regular fluid. This happens all the time. The car has been in storage all winter (7 months), I replaced the clutch with a CM FX400, and no work was done on the release bearing/transmission side as it only has about 8k on it.. I had the same problem last year but it was intermittent, thought I get it fixed this year as it is worse.

EDIT: Found a new master cylinder localy, will try it out tonight.

ZSpeedPerformance

iTrader: (71)

Have you messed with the pedal adjustment? If you have you may have the adjustment too tight, If you do it will be hell to bleed and the pedal can stick down half way.

You need to make sure when the pedal is returning to the top position that the clevis/master cylinder rod stops moving before the pedal is completely at the top of the stroke. If it is adjusted too tight the fluid cannot get back into the reservoir and on the next pedal stroke all you are doing is pushing whatever fluid is in the master at that time. This will also make it very hard to bleed correctly.

Boosted Performance

iTrader: (14)

Thank you for the reply. I will keep an eye on this when I do the bleed again tonight. I thought it was taking too long to bleed, so this is possible, although I did not mess with the pedal adjustment bolt.


EDIT: After reading that again, I am sure the clutch was being returned all the way back far enough not to cause this problem. (I read it too quick the first time)

ZSpeedPerformance

iTrader: (71)

Master is probably bad then at this point, If adjustment is correct the onyl thing it leaves is the master basically or air in lines or combination of both.

terrasmak

iTrader: (8)

Its what i said. The pressure plate pushes it back most of the way, then the spring inside of the master finishes the job. I bleed, adjusted etc etc on my 05 and nothing, then i called Fontana Nissan and got a rebuild kit. Quick rebuild, probably not even needed, cleaned the gunk out of the master bore and works perfect now. My 03 has yet to have this problem. I'll probably just rebuild both in the off season when i install the new motor.

ZSpeedPerformance

iTrader: (71)

The spring in the master is only to return the piston in the master, It has no where near enough power to return the pedal. The clutch in combination with the pedal return spring returns the pedal

terrasmak

iTrader: (8)

What is actually happening is, even if you return the pedal by hand the piston in the master is sticking. Both the pedal spring and spring in the master finish the return.

Boosted Performance

iTrader: (14)

That's the thing, the pedal return spring does not even seem to compress on the down ward stroke of the clutch peds. It rather "flops" up and down vs going back and forth. It was late last night and i just got frustrated....will have a better look at it later.

To me it looks like the bracket (top of the clutch pedal) where the return spring is, is in the wrong place as fare as leverage goes. That was my observation.

ZSpeedPerformance

iTrader: (71)

The pedal spring is dual purpose, As you push the pedal all the way to the floor it will roll over and actually help you hold the clutch on the floor. This eases effort while sitting at stop lights ect for normal people

As the clutch pushes the pedal back up it will flip back over and return the pedal all the way to the top to shut the switches off and hold them off when you hit bumps that could jar/bounce the pedal down a bit and kick your cruise off.

Boosted Performance

iTrader: (14)

Replaced the clutch master cylinder, and was able to bleed the system (now I owe my wife a massage because her leg is sore). Women...what can you do..

The clutch pedal feels great; it shoots right back to the top where it should be. Now I just have to break in this new clutch, it's a bit jittery off the line, but that will go away once the break in miles are through.


There is a clunking noise when parked after depressing the clutch quikckly. Post 17 here:

https://my350z.com/forum/2003-2009-n...estions-3.html

tells me that this is normal. Never had this before, and I can definitely hear the JWT flywheel chatter. I think I am good to got though, but will keep an ear out for to see if this clunking nose gets worse. It is only audible when parked, in neutral, when clutch is released from the floor quickly. The clunk happens when the clutch pedal is 3/4 of the way back up to it's normal position. I think this is due to the fast return because of the new master cylinder.


Thanks again for all the help.



UPDATE: (for those that do search down the road with a similar problem)

After 100 miles of driving, the clutch is feeling very good becoming stiffer (vs a bit soft after the bleed). I had to pull the clutch stop bolt/nut almost all the way back because it seems like the clutch is engaging a bit higher than it did after the first bleed.


So the clutch master cylinder has been the issue all along.

ian99rt

iTrader: (12)

If you have any reason to take the system apart again i may suggest following this DIY i wrote up.

https://my350z.com/forum/engine-driv...tch-pedal.html

It explains the clutch pedal spring assembly and how to modify it for lower pedal released position (reduces total pedal movement).

Honestly best free (for me) mod i've ever done. Makes a huge difference in driving, far more then a short shifter.

terrasmak

iTrader: (8)

I think that was mentioned in the 2nd post

StraySheep

iTrader: (9)

I have the same problem and may have to replace the clutch cylinders.

Just bleeded the clutch fuild bleeded for the 2nd time because it was sticking after the initial bleed. Will wait and see if pedal still sticks duirng hot weather.


If the problem isn't the fluid, how do I know if it's the master cyclinder and not the operating cyclinder?

CuztompartZ said there's crap build up in the master cyclinder (the one close ot the clutch fluid resorvior), but I don't understand how can there be build up when this cylinder is under the hood and away from the rain and salt?

The operating cyclinder on the other hand is exposed much more to the elements and it doesn't have crap build up?

Should I just replace both cylinders when doing the master? Since the operating cyclinder is pretty easy to replace compared to the master cylinder.

Thanks.

terrasmak

iTrader: (8)

The gunk is a build up of sediment that came off the master cylinder piston, the cap, flexable line and even contaminents that were in the fluid.
One is called the clutch master, the other is called the clutch slave. The master on this car is typically the one with problems. Rebuild kits for either one are only $15 each, i would suggest just rebuilding both, it is simple and easy.

What happens, the master cylinder is properly properly in one direction, the sediment just does not allow the piston the return all the way back. Doesn't even really need a rebuild , just needs to be taken apart and cleaned. Since you have to pull it apart, just replace the $15 worth of parts.

StraySheep

iTrader: (9)

Any one has the part numbers for these master and slave cylinder rebuild kits?

I am planning to order them this week from the local nissan dealer.

Thanks.