280z 5-speed clutch won't disengage

[Awk34]

I have a 240z with an engine & 5-speed from a 280z. I've always had trouble shifting into reverse, but now it seems like the clutch won't disengage at all.

I've installed a new slave cylinder and bled the line (I think I did all this properly 😅). I've also adjusted the clutch pedal almost all the way out. Attached is a video of the slave cylinder actuating under full petal press. It seems like it's not traveling as far as it should. I took the boot off for visual reference.

[ETI4K]

Definitely not enough stroke.  Likely to be either air in the line or a master cylinder that's leaking at the piston.

Is it perhaps leaking fluid from the M/C into the interior?

If you believe the M/C is okay, I'd start over with bleeding.  In fact, I'd prolly replace the piston seals in the M/C (just for fun and certainty) and replace all the brake fluid.  Start clean.

Bench bleed the M/C, then reassemble and bleed the system.

 

Edited June 5, 2021 by ETI4K

[cgsheen1]

You have the wrong length collar on the throw out bearing. Your clutch fork end should be much closer to the slave cylinder. The slave cylinder push rod should normally be pushed in about as far as it will go as it's static position. Unfortunately that means pulling the trans back to expose the collar and throw out bearing for replacement. (you're buying transmission & engine parts for a late 280Z (1978) or 280ZX - not a 240Z - correct? Just checking...)

Edited June 6, 2021 by cgsheen1

[Awk34]

The clutch master installed on the car when I got it was bad. The pile of parts the previous owner gave me had another master in it, but I have no idea if that one was also bad. It was at least better than the first one.

I just ordered a new one. The seal kits look about the same price as a new cylinder.

 

@cgsheen1 are you sure? I wouldn't be surprised. I haven't done anything to the clutch since buying this vehicle about a year ago, so it's not unlikely that the PO installed something wrong, b/c there was a lot installed wrong on this engine..

Yes I believe it's a 280Z trans. It's an L28 block and a 5-speed. Did they make 5-speeds for the 240?
I recently installed this shifter: https://www.thezstore.com/page/TZS/PROD/classic22c01/20-1050

[cgsheen1]

99%. There were no US 5-speeds until the late 280Z and were offered as an option. The 280z came with a 4-speed stock and the lates had the 5-speed option. The 280ZX came with a 5-speed and it's more likely to find one of those. They were all L-series engines and that's a very popular swap. There are threads that describe how to tell what 5-speed you have. Easiest way is to look at the bolt that fastens the speedo pinion gear body into the trans. If the bolt is on the bottom, it's from a ZX..

None of that means a great deal with your particular problem except you want the correct slave cylinder for the trans. Your issue is more likely the clutch package. The clutch package (dimensions of the pressure plate) determines which of the several available throw out bearing collars you need to use. That's the "adjustable" part as the fork pivot, fork, slave cylinder and it's push rod length is fixed. The adjustment in the clutch master cylinder rod is for clutch wear and personal preference of clutch engagement.

When you have the proper collar installed, the fork should push the slave rod almost all the way back into the cylinder. The end of your clutch fork is way too far forward...

Edited June 6, 2021 by cgsheen1

[Awk34]

If I want to just replace/refresh everything in the clutch area, can I just buy everything for the 240Z?

I only see a collar for sale on thezstore for a 240z: http://www.thezstore.com/page/TZS/PROD/classic22b01h/21-2121

[cgsheen1]

You can, but I wouldn't. Your trans and clutch parts are either 280Z or 280ZX. And, you should figure out which. Collars can be found and there's a HUGE thread discussing the various collars and clutch package dimensions. You might want to check it.

[heyitsrama]

New clutch collars are available from Courtesy Parts Nissan in Texas as well, I just ordered mine from there.

Here was the thread.

 

[Awk34]

oh they have it, it's this one: https://www.thezstore.com/store/merchant.mvc?Screen=PROD&Store_Code=TZS&Product_Code=21-2122

[heyitsrama]

What kind of problem do you have with getting into reverse? I find myself putting the gearbox into 1st or 3rd and lurching a bit with the clutch, then I can try for reverse. Otherwise sometimes it feels like I cannot pull the gear lever back into place.

[Awk34]

I've had shifting into reverse work a few times, but usually when I try to shift into R with the clutch depressed it just grinds. I had to turn the engine off, shift into R, turn the engine on with the clutch depressed, and slowly let it out. Shifting into the forward gears didn't have any of those issues.

[Zed Head]

We've posted about the correct distance from the slave cylinder bolt head to the fork.  You might measure that at rest.  That will tell you something about the TOB collar/sleeve inside.  If it's too short the distance will be too long.

It doesn't look like the fork is hitting the back of the hole.  That's what usually happens with the wrong TOB sleeve/collar.  Yous still looks like it's back farther than normal, but there might enough room to make it work even though it's wrong.

The FSM shows the slave cylinder travel number.  You could measure that to see if you're getting full travel.  People have made their own slave cylinder rods to get more reach to the fork.  But it might also be that the rod at the master cylinder is the one that needs to be extended.  You said that you adjusted the pedal, but not the rod from the pedal to the MC piston.  You can do that by loosening the lock nut and turning the rod with a pair of pliers, while everything is assembled. Take the return spring off of the pedal and extend the rod until the play is removed, but leave a small amount, the put the return spring back on. It's cramped under there but it's doable.

It does look you should get more travel in your video, which might let you get by with the wrong parts for a while.