tazman71

iTrader: (1)

Hey guys. I just had my trans rebuilt, and had to replace the throwout bearing.
I got it all back together, and the clutch pedal will not push down. At least without blowing the master cylinder up.
Anyone know what the problem might be?

bigj2717

iTrader: (15)

Make sure the clutch fork is seated all the way on the throw out bearing.

tazman71

iTrader: (1)

Wouldn't the pedal be easy to push if it didn't engage the bearing correctly?

bigj2717

iTrader: (15)

Mine wasn't I pressed the clutch and it broke the slave

FormulaJoe

iTrader: (5)

You need to bleed it. Trust me. If you don't bleed it enough/ leave it at a certain random point in the bleeding process I've noticed my clutch petal is like a rock. I'm 99% sure that all you'll need is a good 30 minutes to bleed the hydraulics. Took me about a half hour and I was still getting a couple bubbles. But I said F it and slapped it on and she works fine.
Try a good bleedin.
Hope that helps!

IronOutlaw

iTrader: (4)

You may not have installed the slave cylinder correctly. If the end of the slave doesn't seat into the dimple on the clutch fork you can't push the pedal down. Pull the slave. Carefully reinstall it.

tbag_skywalker

Same here.

Except replace "broke" with "blew up".

OP, you'll know the clutchfork is fully engaged when it is centered exactly between the two studs that stick out of the bellhousing that the slave bolts up to.

AR15 guy

iTrader: (1)

Did you get a new GM slave and master or is it in the old stuff?

tazman71

iTrader: (1)

I am using the old system. Reason is it was replaced when the clutch was replaced about 5 thousand miles ago. The clutch, flywheel, pilot bearing, throwout bearing and slave were all replaced at that time.

I had a noise that I thought was the trans, and sent it to RPM to have it gone through. They informed me it did't have any real damage and I decided to have it refreshed and upgraded to level 4 since it was already apart.

I then checked the throwout bearing and found it to be the culprit of the noise. I ordered an LT4 bearing and reinstalled everyghing this weekend.
I was very carefull to put the clutch fork back in and made sure the slave was seated in the fork. Then I put it on the ground, and sat in the seat, and went to depress the clutch, it was hard as a rock. The pedal is at the top, so I don't think I have any issue with any air or anything in the slave system.

I am planning on climbing back under there tonite to pull the slave and recheck the fork engagement.

Any other Ideas?

tazman71

iTrader: (1)

Also, is it possible that the throwout bearing could be bound up on the input shaft on the trans, making it not possible to release the clutch?

It was a little tight puttin the trans back in, but slid right into place up to the alignment pins on the bellhousing. Then had to pull the trans in with the bolts, which went in easily.

tbag_skywalker

I don't think its impossible, but its extremely unlikely. Its usually a good idea to to put a very light bit of grease on the input shaft collar that the throwout bearing slides on, obviously not the input shaft itself though.

I don't want to keep pushing the "make sure your fork is engaged completely on the bearing," but that sounds exactly like what your problem is. The LT4 throwout bearing is square shaped where the fork slides over it, so it makes it kind of tricky to get it engaged right. A few years back I thought I had the fork on right, using the same bearing, and my pedal was completely stiff. So like an idiot I pushed it anyways, and my slave cylinder puked all over the place, literally exploded.

If the "cup" on the end of the fork is exactly centered between the two studs for the slave cylinder, you should be fine.

tazman71

iTrader: (1)

That seems to be my problem. The clutch was completely still. I did just what you did. It blew the slave apart. The plastic mounting holes broke off of the slave.
I tried messing with the fork some more, and it will not move, even with a hammer(I didn't get crazy with this).
Is the LT4 bearing supposed to be aligned in a certian direction for correct fork engagement?

tbag_skywalker

**** lol, sorry to hear about your slave cylinder.

I never paid attention to the position of the bearing (though I wish I had), and always managed to get the fork on the bearing properly. Sometimes it took more messing around than others, but I always got it.

Is the fork stuck in place now?

tazman71

iTrader: (1)

The clutch fork moves just fine. When I align it with the bearing, it is positioned centered with the 2 slave cylinder bolts, but will still not move.
I think that the square shape of the LT4 bearing is catching the fork not allowing it to move. Wish I would have checked it out before assembling the trans back in.
New slave on order, and the car is going to the shop, since I am running out of time to get this together. Heading to the Pontiac Nationals in 2 weeks.