I have an 03 G35, fully built..just got it back from the shop about a month ago and finally had a nice day to take it for a ride. They installed a Spec D Dual Clutch. After several miles the pedal would briefly stick..then after about 20 miles the pedal didn't even want to come back off the floor. The shop won't contact me back or make anything right. I extended the pushrod as far as I could but have not taken it for a spin yet as the weather has been ****.

Anyone else ever have this issue before? Any thing else I should be looking in to?

Thanks.

 

I had that problem in my previous 06 G35. The dealer took care of the CSC under warranty. Never had another problem and traded in the vehicle at 171796 miles still with the original clutch.
Check your CSC, Clutch master cylinder, air, improper clutch fluid,?

Follow the troubleshooting steps in the FSM.

https://www.nicoclub.com/service-man...F2003%2Fcl.pdf

Good luck

 

Have someone else press the clutch while you watch to see if the slave cylinder piston actuates. My guess is the heavier pressure plate/clutch of the new system blew out either the CMC or the CSC. If the piston is extending properly then the issue is inside the bellhousing.

 

Well the car only has 48k Original miles but I went ahead and replaced the master cyl and the slave cyl and replaced the line with a DEI right before I brought it in for them to work their "magic" but I will look in to that other stuff as well. Thank you.

 

What brand master and slave cylinders did you use?

You need to have the rod adjusted correctly or you will burn out your clutch, fix that back to where it was. It's also notoriously hard to adjust on these cars due to the helper spring numbing the normal feedback you'd feel.

Since you already have new cylinders, here's some other things to check: the 03 had some dumb restrictor orifice in the clutch hardline. If you remove the splash shield in the fender you'll see it. Some guys drill it out, other replaced the hard lines with one from a newer G35. That think can be causing problems with an aftermarket clutch. The other thing is to look into deleting the "helper spring" that's on the clutch pedal. If RJM is still around selling adjustable pedals, get one of those. Was one of the best things I did to my 6MT.

If you had the old master and slave still on the car, I would've just recommended flushing out the clutch fluid since old fluid is a big cause of the stuck on the floor pedal issue. My hunch is that orifice not playing nice with the upgraded clutch, or the replacement cylinders already failed.

 

Well when I first bought the car 7 or 8 years ago if I was doing donuts or something it would randomly stick to the floor. It had an aftermarket clutch and flywheel then. Then I replaced the whole transmission with a brand spankin new one and thru a stage 3 clutch and flywheel in and I flushed the whole system. This was 2 years ago. It still wouldn't get pedal, so I replaced the slave and master with autozone parts and the DEI line thinking it maybe a heat issue..still no pedal, so I adjusted that rod and then it worked fine..I mean it engaged. I never drove it besides down to the end of my road and back. Its been to 3 different tune shops in the last 2 1/2 years. 2 shops it sat for a year each. The 2nd shop blew thru the clutch. I got tired of him and hauled it to another shop who told me the clutch was garbage. So I had them replace it.

It feels as if the issue could be the pedal cause it clunks. But also if I grab it and just give it a little pressure upwards it will clunk back up. So thats why I adjusted the freeplay out of the rod hoping it will have adequate pressure to push back up. I don't know. Waiting on nitrous purge and a bigger intercooler before I can put everything back together and take it for a spin..

I seen a video the other day about someone removing or changing the spring to give you the normal feel of a clutch. I'm going to look in to your advice right now.

Thank you.

 

Sounds like you might have something binding up the pedal itself. Remove the clevis pin and unbolt the CMC so you can pull it forward a little then work the pedal by hand and see if it's sticking.

Also might be binding up the throwout bearing on the transmission input shaft seal if it's got a lot of dried up crusty oil leftovers and no one bothered to clean and use the proper grease when they did the clutch job.

 

Info I found so far just in case someone stumbles on this later..this from various threads.


Clutch Care (rangeracceleration.com)

Bigger Restrictor from nissan 2006 350Z/G35 uses. Part # 30859-Z33002
Or drill out stock to restrictor to 7/64"
Or Replace with a Dorman 785-438 connector which is 3mm orfice vs the Nissan stock 2mm

Orrr..

What I ended up finding was this video

You Tube

It is a line that just replaced the whole oem line and deletes that restrictor all together, he has a link in the desc but their website sucks and it is Sunday so I can't call and I am impatient so I went to eBay and found
eBay item number: 360908984221 and went ahead and ordered it.

 

I also removed the clutch spring competely. I tried a different spring and I don't like it so I am going springless. People say they put a different spring in rather than take it out completely to avoid side to side movement or any free play, but mine has no freeplay with it removed completely. So I am going to see how it goes once the rest of my stuff comes in.