unicoder

1995 240sx 145k miles

Changed the OEM clutch to an Exedy ProKit clutch and lightweight flywheel package off of eBay, now when we press the clutch pedal, the clutch itself will not disengage. After a few days of searching here and re-trying steps, I feel I am ready enough to post here and ask about it.

As it sits right now
- Slave Cylinder replaced and bled, pedal feels good and strong, and the clutch fork travels as much as our other 240sx when the pedal is pressed, but still the clutch doesn't disengage. We also adjusted the clutch pedal for the maximum throw.

- Per another thread, we jacked the back of the car into the air and just started running through the gears a while hoping it would eventually catch and start working. That did not help much at all.

- The pilot bearing from the kit would not accept the input shaft, it simply wouldn't fit over it. We ran to AutoZone and got another Pilot Bearing, and it wouldn't fit over the shaft either. We finally just reused the old bearing as it was the only one that would fit.

- I checked to make sure the disc slid on the input shaft before installing it. The clutch fork is on the pivot ball and the slave cylinder rod hits the dimple for it dead on.


We have spent many hours researching this problem on here this weekend. I am already very grateful to all of the suggestions and information we have found so far, but for some reason we are still lost on this issue.

Could it be the master cylinder? It was working fine before we changed the clutch, I don't really see any reason why it would randomly go bad during this weekend of all times.

Tarmac Attack

While you had the car in the air, did you have someone underneath verify that the slave was actuating the fork when you press the clutch pedal?

unicoder

Yes we did

Dirk Jan

Have heard of this issue before. In that case the clutch disc was fitted upside down.

__________________
@dedirkjan

unicoder

Upside down? Do you mean backwards?

flartius

What?


Sent from my iPhone using Tapatalk

__________________
¯\_(ツ)_/¯

Tarmac Attack

He probably does mean backwards lol. Is it possible the disc was installed backwards, because it is side specific. Also, the sleeve that the throwout bearing is pressed on to, what condition was yours in? I just finished a 5 speed swap in my car and my old one was wiped out, like the lugs where the fork would engage it were so worn down, I just replaced it.

unicoder

Good question! The sleeve the TOB is pressed onto looked really good actually. I was surprised how good of condition everything was in.

But as for the disc, I am pretty sure it's installed right because the hub on the front of the disc sticks out and makes it really easy to see which side is the front. We are going to drop the trans again just in case and take photos.


Sent from my iPhone using Tapatalk

__________________

5.3 V8 Swap w/ Nitrous

unicoder

Here is a shot of behind the fork. Resting on the pivot ball, and retaining spring still in place



Not the best shot, but of the TOB pressing against the pressure plate while the clutch pedal is pressed.



Sent from my iPhone using Tapatalk

__________________

5.3 V8 Swap w/ Nitrous

di-devol

You just did a clutch and didn't clean anything? Or is all that oil in there new?

__________________

unicoder

I didn't clean the inside of the bell housing or the pivotball, I just wiped it all down. The input shaft, throwout bearing, bearing "sleeve" thing, and fork face were all cleaned.

The bearing in the pic looks oiled but that is the grease I used on the bearing and input shaft.

I apologize, and know that some people like to give it a good cleaning, but I didn't. Perhaps I will this weekend when we take it all back out.

cotbu

Ive seen this a few times. So this is assuming everything is installed correctly. Depending on pressure plate design, the fingers can get broken and wedged behind the friction surface and the pp. If that happens or a foreign object is introduced there, then the clutch can't be disengaged.

It usually happens when the trans shaft slides down the face of the pressure plate, during an incar install.

You can usually lift the rear wheels and 4th gear, crank it over and jolt it loose. Violent and loud but it works not recommended because it will lock up again. Just pull it and remove pp and knock out the object. Reinstall or replace clutch cover.

Sent from my LG-H631 using Tapatalk

__________________

LoverTechnologies "Half Broken Things!"

unicoder

The input shaft definitely didn't hit the splines on the clutch the first stab. I will look for this when we remove it. Would I need a whole new pressure plate?


Sent from my iPhone using Tapatalk

__________________

5.3 V8 Swap w/ Nitrous

cotbu

No, not in that case.
When you pull it apart look at the disc too. A spring could also be broken.
I dont know what the actuall problem is, I've just seen it before.

__________________

LoverTechnologies "Half Broken Things!"

unicoder

Alright, I hope you're right! We are going to change my master cylinder and install a stainless line to the slave cylinder first just to ensure it's not a pressure issue. Then we will yank it out and see. Thanks for the suggestion


Sent from my iPhone using Tapatalk

__________________

5.3 V8 Swap w/ Nitrous

unicoder

FYI 4th gear crank didn't shake anything loose. Thanks Flartius for helping out on wrench time when I'm not there!


Sent from my iPhone using Tapatalk

__________________

5.3 V8 Swap w/ Nitrous

flartius

Sent from my iPhone using Tapatalk

__________________
¯\_(ツ)_/¯

bfellini

I would venture a guess and say the stack height is possibly wrong, so the release bearing isn't moving the pressure plate fingers fully.. The fact that the pilot bearing was wrong, and it was an eBay package, could mean the clutch was for a different car, with a different required stack height, or the flywheel surface may be recessed more, both resulting in improper engagement issues... if this is the case, there are taller release bearings, and longer sleeves from different models

unicoder

I bought it from gripforce's ebay store front. I didn't buy a cheap eBay knockoff. I don't agree that stack height is an issue. I am not stubborn though, I will measure it when we take it out.

And for the pilot bearing, even an oem from Autozone wouldn't fit my shaft, so I don't blame gripforce for that.



Sent from my iPhone using Tapatalk

__________________

5.3 V8 Swap w/ Nitrous

bfellini

Wasn't implying you or it was cheap! Just have had this issue myself in the past


Sent from my iPhone using Tapatalk

unicoder

Sorry!


Sent from my iPhone using Tapatalk

__________________

5.3 V8 Swap w/ Nitrous

unicoder

We fixed it this evening. Tore it apart, but everything looked good to us. Must have been an issue with the pressure plate.

Put an OEM clutch & flywheel on it and everything worked like a charm. Heck even the pilot bearing with this kit actually fit the input shaft!

Thanks for the help guys

unicoder

Actually just noticed the clutch disc they sent was for a 70s 240z, that's probably why it didn't work.


Sent from my iPhone using Tapatalk

__________________

5.3 V8 Swap w/ Nitrous