pilot bearing

[erubin]

I already bought a new fork (ordered by application not by matching to the old one) and it is identical to the old one. Assuming the bell housing is deeper, what is the easiest solution at this point? Can a thicker bearing take up the gap? Should I bring the fork to a welder to heat up and bend? Can a spacer be put somewhere in the assembly to take up the space? Bending the fork seems the trickiest because things might not line up right after.

I believe/hope i can do one of the above "fixes" without yanking the trans completly out (ouch). By parting it from the engine a few inches i should be able to reach in and R&R the fork and bearing.

How much of a gap should exist between the thrust bearing and the pressure plate springs when the clutch is moved completely back? and does the slave cylinder allow the fork to move completly back? I really don't know how much travel the slave cylinder provides and if all of its travel is used to compress the pressure plate or some to take up free play like you have with an ordinary clutch.

[busa_4]

i am thinking 3 possibilities: 1: the fork is for the wrong vehicle. 2: the throwout bearing is for the wrong vehicle (unlikely but could happen). 3: the input shaft is missing the guide sleeve. the throwout bearing rides on this sleeve mounted to the input shaft. if it is not there or the wrong length you will experience the problem you are facing.

[erubin]

Thanks for trying to help:

1. the fork is correct for the vehicle on two accounts. a) it was already there. b) i ordered anew one based on the year, make model of the truck and it's identical to the old one. this is not to say that the trans is not original to the truck though.
2. the throwout bearing is correct for the above reason as well. the Napa diagram i showerd in a previous post also looks identical.
3. The bearing rides on the trans input shaft sleeve perfectly. the sleeve is not missing.

I think Overboardproject who posted a few back was onto something when he wrote: "The other possibility is the bell housing might have been changed before."

Back to my question. how do i take up the gap now?

[busa_4]

if overboard is correct, i think it would be better and safer for you to find the correct bellhousing.

[busa_4]

do u have a digital camera? i want to see what this looks like.

[OverBoardProject]

I agree with Busa 4, It might be tough or imposible to find the correct fork for the bell housing.

If you try bending the fork it'll probably break, however welding on a plate to shim it might just get you bye until you feel like pulling the bell housing

Good luck, and if you can send Busa 4 a photo of the bell housing he might be the best advice to make things stock again.

[gaggrouper]

An interesting problem. I'm not aware of a spacer. As you likely already know, the back half of the bearing is designed to accept the fork and the front, as you mentioned, engages the spring assembly. The trans on my truck has a one piece casting, that is, the bell housing is part of the case not bolted to it. Not sure where your problem is. Not sure what kid of money you have in this project, but with the number of these trucks out there you might consider getting a used trans from a salvage yard. Of course, only after all else fails.... Just a thought. I think at the very least you need to find out if you have the correct bell housing and fork. Just can't see why anyone would switch them. How did you acquire the truck and is it possible to contact someone with info on it?

[erubin]

I found another throwout bearing at a parts store. It's the bearing for an older (80s?) GM setup. This bearing has an extention ring (about 1") behind the front half of the bearing. This takes away an inch of slop between the fork and pressure plate. It's gruelling work doing the trans R&R alone with just a floor jack. It should have been easier then the first time since i only had to slide the trans back about 5" and slip in the new throwout bearing. Getting the trans and engine to mesh up again was hell. It finally slipped right in when i lowered the tail of the trans a little more than seemed correct.

Now the slave cylinder is completly compressed and the throw out bearing is in contact with the pressure plate in the rest (clutch engaged) position. I hope that is what it's supposed to look like. The clutch pedal feels firm and the pressure plate gets compressed about 3/4" of an inch when the pedal is depressed. Eureka!? I hope so but won't know till I get everything back to gether and test drive later this week.

[busa_4]

so what your saying is you have an older 80's tranny in your vehicle. if the spacer works that should confirm it.

[OverBoardProject]

I sure hope that it all worked out for you.

If it does make sure that you write a little referance note in your owners manual, and shop manual if you have one, including year, and part number of the bearing.

[erubin]

I haven't had time yet to go further. when i do I'll update this post. I can't believe that the trans is from a early 80s vehicle. Afterall the other clutch parts (spec'ed for a 1992 S10 4ctyl) seem to match up fine. I don't want to say too much more until i try it out.

[OverBoardProject]

If that new bearing works out well you might want to buy the guy from the parts store.. that found the right bearing a christmas beer for the help.

Congrats on your first clutch job, and the rest are all easier

[erubin]

Finally got back to the truck. The nightmare continues.

everything is installed and the truck will not allow shifting 9can't get into forward gears and grinds going into reverse. I suspect the clutch pressure plate is not being pushed in enough. Please advise:

1. how far should the pressure plate get compressed when clutch pedal is fully depressed.
2. My slave cylinder only pushes in the fork about 3/4" (measured where the slave push rod contacts the fork). Is 3/4" enough?
3. I have bleed both cylinders countless times by using the old brake bleed method of pumping and then keeping pressure as the bleeder is opened. i installed a new master. the slave is only 1 month old. neither is leaking.
4. I will replace the slave cylinder unless someone can give me some other advise.
5. If 3/4" fork throw is enough could a bad trans cause this problem?