jason350z

iTrader: (8)

So recently I got an os giken dual plate clutch installed with the czp S.C . the shop who installed it did have problems trying to bleed the clutch but finally they were able to get air pockets out. The problems they had was that the pedal would not come up all the way. After the install the car drove fine, the pedal/ engagement was pretty low but over time the clutch pedal/ point of engagement has come up to near stock level. The problem I have is that if a stop at a light and try to shift into first gear I feel more resistance sometimes its hard to shift into first gear and sometimes I have to force it “which I don’t” but i pump the clutch a few times and the it shifts.
Also yesterday I parked the car left it in first gear and when I went to turn it on I press the clutch to go to neutral before turning it on but the stick shift was stock in first gear and it required some force to get it out. Not a lot but if was hard. Once you turn on the car its normal and when you drive the car it shifts fine no noises or anything. What could it be?

Could there still be air in the clutch lines?

What if they order the wrong slave cylinder?
Or what else can it be? I’m worried cause I don’t want to miss up my trany. Or is this clutch supposed to be like this???????????????

thanks

Neal516

the issue is having enough "throw" on the slave to release the clutch completely. try adjusting the clutch pedal outward, so the pedal sits higher, and you have more travel on the master cylinder.

jason350z

iTrader: (8)

i think the shop try that cause initially the pedal was not coming up all the way. so the way the pedal feels very soft 1/4 at the the top and once the clutch engages its harder. im still having the same issue if i stop at a light and go into neutral when i try to go into 1st gear it kind of lucks, like something is not weel aligned and i cant go into first. i have move the shifter around try to getting to go into first smoothly and it will eventually go but that **** is not normal. once u start moving the car drives fine.

Italianjoe1

iTrader: (6)

I just recently put the same setup in my car, os twin and the Zspeed slave/master combo, it was super easy to bleed and with the larger master I have the exact opposite problem, the release is all the way up and it's hard to take off smoothly because my foot is almost off the pedal before the clutch grabs, no matter how I adjust. I already ordered a smaller master from Joe at Zspeed (great guy btw, excellent customer service) to help with that part.

If it feels soft, you still have air in there somewhere. Have it bled right, and i'd suggest switching out the master cyl as your next option, as it sounds like you just aren't getting enough fluid into the slave to totally release the clutch.

jason350z

iTrader: (8)

thanks alot man.

yeah the engagement used to be just a few cm of the floor and as they kept bleeding the clutch engament came up, also as i drove the car it came up to near stock levels. because the pedal would not spring out all the way the adjusted something at the pedal "i think". now the pedal springs all the way back but it feels wrong "as you press the clutch 1/4 in it feels like there is no conection to anything and then you feel it getting stiff i guess point of engagement. if the pedal is press all the way in and i let go it springs up fast 3/4 and the last there is a little delay sometimes it trys to stick. i think there is still air in there.
what would be the best way to bleed it again?

Italianjoe1

iTrader: (6)

Best way to bleed it is with a vacuum bleeder, from the resevior, it will pull the air out.

Although, what you have sounds like a master cyl going bad. It's still the original stock one?

jason350z

iTrader: (8)

Yes stock, never had problems with it until I got the clutch. About 2-3 weeks ego. Car only has like 30k miles

Italianjoe1

iTrader: (6)

Yeah this clutch has so much more spring pressure than stock and the aftermarket slave has different fluid capacity and pressure needs than the stocker.

My OEM master was starting to act up anyway, and I was only at 50K miles.

My suggestion is just replace it, preferrably with the zspeed upgraded one to match your slave.

musubi

iTrader: (1)

From working on my truck and car (Z) a little, it sure sounds like you have air in the lines. After some reading on bleeding the Z, the Z has some issues with allowing air to escape. On CZP's website, somewhere on there does explain to loosen the hard line connection to the master cylinder to allow air to escape. Apparently air has a tendency to collect there. Correct me if I'm wrong.

Anyways, the way I bleed the clutch system now is through reverse bleeding. Bubbles want to travel up, so you push it up. Same thing as vacuum bleeding.

I know when I couldn't depress my clutch all the way down in my truck (due to my pedal mount breaking), I had a real hard time shifting to 1st and reverse.

jason350z

iTrader: (8)

thanks everyone. talked to Zspeed they said it could be the master cylinder, they also said they are in the proces of tring a new master cylinder for the os giken that will allow the clutch engagement to be lower. so might wait for it. will also try to have the clutch bleed again.
they also old me it could be that the clutch was not adusted- not really sure what they ment however they said its more likly to be the master cylinder

Italianjoe1

iTrader: (6)

Yeah i'm the one trying the new master, I ordered it last friday. He normally sends the same one with all the kits, I talked with Joe about running a smaller one and he said he's been wanting to try that for a while anyway, so I bought another one and am going to swap it in. Hopefully it works better and he can start to use them on the OS twin/triple kits.

jason350z

iTrader: (8)

so when is that going on your car?

also how high was the engagement with the one you have now. was it like stock which is kind of high

ian99rt

iTrader: (12)

I would absolutely suggest replacing the master cylinder. The orifice block behind the fender liner makes bleeding the oem clutch a nightmare. Removing that from the system makes bleeding a 5 minute breeze.

The gunking up of the factory master cylinder is likely the incompatibility of the long reservoir hose that degrades and causes the sludgy build up.

Joe @ Zspeed recently changed from the wilwood MC that has a built in reservoir, to a master that reuses the oem reservoir. If it were me i'd ask him if he can provide the built in reservoir kind.

I run accelerated fluid compatibility testing at work all the time and my OEM MC looked exactly like a failed fuel soak test.

Italianjoe1

iTrader: (6)

I haven't got it yet, once I do it will go on very quickly, as I don't care for the clutch the way it is.

My engagement is almost all the way up, I can step down maybe 1-1.5" and shift, it's fully released already. Slipping the clutch to take off is a ***** and a half, as by the time it starts to grab my foot is basically off the pedal, and with this strong clutch it just snatches the car forward.

Italianjoe1

iTrader: (6)

Agreed, the stock line is horrible, I removed everything with the Zspeed master/line/slave setup, let it gravity bleed for about 3 minutes and was done. Seriously, I didn't have to pump the pedal not even one time and I got 100% of the air out.

The remote resevior is more to accomodate the ESC cars not having enough room to clear the built-in one. If you cleaned it properly the stock one could be re-used just fine. My nismo doesn't come with the larger ABS box though so it wasn't an issue, all the stock parts are gone.

67ZNISMO

iTrader: (6)

Which master did you pick up from Joe? Did he release a new one recently? I have the same setup (OS/CSC/Wilwood MC) and my engagement is up high as well. I'm still working on bringing her down which seems to be working a little at a time.

Italianjoe1

iTrader: (6)

He sent me the normal wilwood that he always uses. I called up and asked about a smaller one, so we are trying a 5/8" (.625) versus the normal .700" I/D master. I honestly think I could go a lot smaller but i'll try this first and see how it works out. I may drop it down another size if this doesn't get my pedal back into the middle area for engagement.

What have you been doing to adjust it, just play with the rod?

jason350z

iTrader: (8)

Today we bleed the clutch and turns out there was an air pocket in the master cylinder, like you guys mentioned.
the pedal feels just like Joe described it , engagement pretty high. After we bleed the clutch the first time the pedal felt soft ¼ at the top, I told the mechanic he looked a it a second time and now the clutch pedal has the same tension all the way from the top to the bottom. First gear and reverse go in much better. Occasionally a little stiff but nothing like it was. I think there may still be a little air in the line cause the second time he looked at the car I didn’t “see” him bleed or open any lines for air. maybe the air moved around with in the lines, will see how it behaves the next few days. Now waiting for GTM stage 1 TT to be delivered and complete this project. Hmmm not really there’s always something else to do or fix.
Thanks everyone for their help!!!

67ZNISMO

iTrader: (6)

Yeah I'm just adjusting the rod but I'm not going very far anymore. I'm curious what the smaller mc will do. If it can make the engagement a little lower im down to pick one up. My pedal is really stiff....I'm wondering if something is up with my pressure plate

ian99rt

iTrader: (12)

My stage 2 southbend clutch had me thinking something was wrong as well. It was really stiff in the beginning but by the time I hit 500 miles it had softened up to about 35-45% stiffer over stock.

Engagement point also moved up a bit as well.