Fairlady_Love

iTrader: (2)

I have an 07 350z with about 46k miles, and I adjusted the clutch pedal after reading the following thread:

https://my350z.com/forum/engine-and-...ent-point.html

It is recommended to turn the adjustment stud anywhere from 2-4 turns, with 4 being the limit. I adjust it to 4 turns and the car drove great - the clutch fully disengaged and the engagement point of the clutch was about a half an inch of the floor. It was awesome to drive.

So I woke up the following morning and I couldn't get the car out of gear with the clutch pedal to the floor. The car would roll slightly in gear when I took the ebrake off, and the clutch would "engage" instantly upon movement of the pedal (because it was already partially engaged). I finally got the car out of first gear and into neutral, and started working pushing the clutch in and out, and put my foot under the pedal and pulled up on it. After a few times of doing this, the clutch worked exactly as it did the day before, and it was fine. Being worried about it, I decided to back it off one full turn, so I went down to three turns, and it would do the same thing. It is fine once I play with the pedal for a little bit, with one time all I had to do was pull the pedal all the way up and hold it for about a minute and the pedal worked fine after that. It only happens after the car has been sitting overnight, or for a long period of time. The clutch sits really far to the floor when the issue is present, and then after I play with it, it goes back to sitting just below the brake pedal.

It is like the fluid is leaking past the O-Rings in the master cylinder, letting the clutch drop, and then after working it and holding up, the fluid goes back in front of the seals and works like normal, until it has a chance to slowly leak back past the seals (like over night). The longer it sits, the worse the problem.

Has anyone experienced this? Is the issue caused by something else? Anybody have any other theories as to the issue?

Thanks!

logan09

iTrader: (1)

get the RJM performance clutch bracket. OEM bracket/design is junk

CROWLEY

go back and readjust the bracket by one turn .you over adjusted not allowing the clutch to completely disengage. simple fix

Mint Racer

iTrader: (1)

adjusted it too far, or the jam nut didnt get tightened enough and the rod threaded itself down lower. yes thats possible.

RangerDave

iTrader: (2)

+1 on the rjm performance clutch pedal, when i got my Z i did everything you did and more with the stock pedal and everything would turn to **** after being left. what i did which completely solved the terrible terrible clutch setup in the Z is
-RJM Performance Clutch pedal adjusted to my liking
-Stainless steel clutch line
-motul rbf-600 liquid

RJM Performance

iTrader: (2)

As others have noted you've adjusted it way too far. Once you pass the tipping point of the factory spring mechanism the assist spring is constantly engaged trying to force the pedal down all the time which rides the clutch continuosly and can lead to clutch damage in a very short amount of time.

The reason the pedal goes to the floor after sitting overnight is you're constantly pusing down on the master cylinder even when the pedal is fully up now by over extending the clutch rod so the balance port in the master cylinder that equalizes fluid between the reservoir and high pressure side can't do its job.
This port only opens when the plunger in the master cylinder is 100% up. Once you get the pedal adjusted to where it can't balance its typically good only when the car is hot the first day as you described. Then since the MC can't balance the hot brake fluid in the line contracts as it cools overnight sucking the pedal right down to the floor where you have to then pry it back up with your foot and possibly doing damaging the seals in the master cylinder at the same time.

About 1-2 turns of adjustment is about all you can get with the factory pedal before causing damage or other issues. That semi-safe number of turns doesn't in any way take into account any previous service work or adjustment done by the dealer or a previous owners so YMMV.

I'd adjust it back quickly before it causes any clutch or master cylinder damage continuing to drive it set like that.

Fairlady_Love

iTrader: (2)

Yeah after I posted this, I went back and tried finding a post I read a while back. I just need to mod the pedal.

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

This will be relatively easy to do, and I will probably be able to do four turns on the shaft which was a really cool pedal position.

I understand the clutch isn't disengaging when I first get in the car in the morning, but after I pump the pedal, the clutch fully disengages. I agree, after reading the above thread, that my spring was causing pressure on the pedal.

All in all, I think the issue is solved. To be honest, I could either spend the 250 dollars on the RJM piece, or I could just modify my own for free...

RJM Performance

iTrader: (2)

Please don't for a minute think the RJM Pedal system can be acheived for free by doing the mod in that link. That simply allows you to further turn the clutch rod however the AFP Pedal is all about the altered pedal linkage geometry at the Fulcrum Point Adjustment which is where all the real gains are made. That mod will give you nothing more than a stock pedal with the ability to lower the pedal thru the clutch rod but doesn't change the engagement characteristics of the clutch at all.
Also the feel you had with the helper spring artificially riding your clutch all the time won't be there once its modded. The helper spring was holding pressure on the clutch and reducing the total clamp load of the clutch diamphram so it wasn't able to engage as positively as normal or in otherwords made it feel like a more forgiving clutch. That would soften the clutch engagement as it wouldn't grab as solidly and feel great while slowly destroying the clutch. Once modded at 4 turns and that spring isn't riding the clutch anymore it'll still engage the same as stock except lower in the pedal stroke and won't feel like what you exerianced the other day.

Just an FYI before you put a lot of work into tearing the pedal out, cutting it up, welding it back together and reinstalling.

island03z

iTrader: (6)

I had this problem too. Loosen the lock nut and back the rod out (towards driver). Then, BY HAND, screw the rod in (towards engine) until you feel resistance. Then back it out a turn or 2. You have to leave room for fluid expansion.
Took me a couple tries to get it right. After a hard day of driving after everything was nice and hot I loosened it again just a hair and it seems to be good now to where I'm not worrying about it anymore.

Fairlady_Love

iTrader: (2)

Let me rephrase that, in order to correct the issue I am seeing, I can spend no money and mod my pedal. I am sure the RJM piece has its benefits, but modding the pedal will do exactly what I want.

The feeling I experienced at four turns wasn't awesome because it was easy to slip the clutch, it was awesome because it was because the engagement was so low in the clutch travel (almost instantly off the floor). My issue with the stock clutch was the engagement point - it engaged at what felt like four inches from the floor. All I wanted was a lower engagement.

samsniss350z

I'm in agreement with Logan09.