[FrankieT/A]

TOB should have ZERO preload!! That's why you have end play at the top of clutch travel with mechanical linkage. Not only would you have premature thrust wear you would have premature clutch wear. If you rest your foot on the clutch pedal while driving that also wears clutch and thrust main bearing. Sitting at lights with car in gear is also a major contributor to thrust wear as well as TOB wear. Every time you push the clutch in its trying to push the crank out the front the engine. That's why light pedal effort is always best. While disassembly of any motor you can always tell if the car was an auto or stick! FWIW.

[Hammered]

Most newer cars with hydraulic clutches have TOBs with preload conditions. It's not enough preload to wear out the thrust bearing unless there is an incorrect application of parts or installation. Here's another link to look at: http://www.ramclutches.com/Instructi...yd%20Setup.htm

That said, I've read of people having too many troubles with these setups on older cars to think that it's worth the cost and effort.

[FrankieT/A]

"The distance from the bearing when it is contacting the clutch fingers to the fully extended position described above is typically .500-.600 inches.**This distance can be described as ‘preload’ and is the main factor in setting up the factory concentric slave with an aftermarket clutch system"

Hammered,
This is a direct quote from the website you provided. They are calling the actual travel distance of the TOB 'preload' not to mention that sheet is for Ram Clutches using factory TOB's. Preload is usually a term of when a predetermined amount of pressure is applied in a static position. By definition there should be NO preload, meaning no direct pressure on the fingers or diaphragm because that would always cause wear. However, with hydraulic systems there is a finite amount of travel so you would not want any extra clearance because that be "distance" that the TOB would have to take up before it would make contact with the PP. That's why aftermarket hydraulic systems come with shims. With All due respect.

[Hammered]

Originally Posted by FrankieT/A

"The distance from the bearing when it is contacting the clutch fingers to the fully extended position described above is typically .500-.600 inches.**This distance can be described as ‘preload’ and is the main factor in setting up the factory concentric slave with an aftermarket clutch system"

Hammered,
This is a direct quote from the website you provided. They are calling the actual travel distance of the TOB 'preload' not to mention that sheet is for Ram Clutches using factory TOB's. Preload is usually a term of when a predetermined amount of pressure is applied in a static position. By definition there should be NO preload, meaning no direct pressure on the fingers or diaphragm because that would always cause wear. However, with hydraulic systems there is a finite amount of travel so you would not want any extra clearance because that be "distance" that the TOB would have to take up before it would make contact with the PP. That's why aftermarket hydraulic systems come with shims. With All due respect.

Yes, there is a spring in the TOB that causes it to put some small amount of preload on the pressure plate at all times. What the instructions are saying is that you can't compress the spring anymore than 0.5 - 0.6" of travel or it won't function correctly. That amount of preload/spring compression is what they consider appropriate. However, you will find that people who have used these sometimes install them with the spring fully compressed, hence putting too much pressure on the pp fingers. Thus, my caution to David.

And not all hydraulic ToBs are designed to be in contact all the time, with all due respect.

[FrankieT/A]

Yes, the amount of pressure that spring applies isnt even enough pressure to budge the crank let alone cause wear.

[Stuckinda60s]

Any pressure, at all, results in the TOB constantly rotating whenever the engine is running. That was always a condition to be avoided during a clutch installation. That was one purpose of the freeplay, the other was to allow for wear which would decrease the freeplay.

It was easy to adjust the clutch, all you had to do was adjust for about 1/2" freeplay.

[Tom Vaught]

Originally Posted by FrankieT/A

Yes, the amount of pressure that spring applies isnt even enough pressure to budge the crank let alone cause wear.

Not really worried about that deal, unless.

I can easily move the crank back and forth with a screw driver with all of the rods are installed in the engine on a engine stand. This with basically no oil floating the crank and rods in the block.

Typical Thrust Clearance is .007" for the crank. If the crank thrust surface sees a good supply of oil it will slide on the thrust bearing and minimize wear.

Typical pressure to release the clutch (foot pressure multiplied by linkage ratio) will push the crank towards the front of the engine but only for a very small period of actual time.

Most of the time the oil is on the surface of the thrust.

So now if you put a big beefy spring on the throw-out bearing and push the crank against the thrust all of the time you might see additional wear over a short period of time.

I have seen "Ballooning Torque Converters" destroy a thrust bearing in a very short period of time and how much does a "Ballooning Torque Converter" actually move, not much.

My vote would be to let the throw-out bearing find its "happy, happy, happy" positions and forget the preload spring.

Tom Vaught

[David Jones]

Straight from the Keisler instructions.....

The CSC (slave) is designed to be compressed by more than 1/2" by the pressure plate fingers when at rest.
A "cushion is required and that cushion range is from 1/8" to 3/8". Determine the cushion as follows. Install the clutch disc and pressure plate to the flywheel. Install the scattersheild to the engine. Lay a straight edge across the transmission mounting face and measure down to where the clutch fingers would contact the slave. "X"
Compress the slave completely and measure from the flat face of the compressed slave back to the scattersheild mounting surface of the transmission. "Y"
The cushion is the difference of "X" minus "Y".
In my case it's 5/16". Within tolerance.
Just for laughs I dropped the alignment tool back in the clutch. Just like it was before my last attempt at installing the transmission. Easy to do with no tight spots.

It appears I was headed the right way.

I'm going to re-install the scattersheild to the transmission.
Then hook the hyd line back up to the slave.
Then jack the transmission back up into place.
Then slide it as deeply in place as i can get it.
Then take the bellhousing loose from the transmission slide it over and attach it to the engine.
This will have me with an installed hyd line and the ability to work only the transmission as I try to seat the input shaft into the pilot bearing.

I'll be back..........

[The Boss]

Fingers crossed for ya David!

[My442]

I continue to be impressed by the effort and determination by Dave.

Success is 10% inspiration and 90% persperation.....

I converted a 70 442 from automatic to a four speed. Did everything on jackstands in a one car garage.

It took me 7 nights in a row of cussing and fighting to get the transmission to go in the last 1/2".

The payoff is a sweet shifting big block car that provides me with endless pleasure.

Dave, once you are done, the sweet taste of victory will soon make you forget about the problems you are having.

Hang in there!!!!!!!!!!!

[GOAT WHORE]

David, the pay off is going to be great. I just got my car going over the weekend and it is awesome! I don't know why people are complaining about miss shifts but then again I am not power shifing either. I think I am going to have to go to a 3.73 gear as my 3.55's seem to tall. I am going to seo e a bit more though before I decide. You are going to love it!

[David Jones]

I took the scattersheild back down and rolled the trans back under the car. Bolted the scattersheild back to it. Re-installed the hyd line. Worked it all back to within that last half inch. Put the crossmember back under it and lowered the jack down. Supper time. I've got a date with it tomorrow afternoon at 4:30.

Thanks guys.

[David Jones]

The input shaft is not completely square on the end.

[Stuckinda60s]

Did you trial fit the bearing on the trans' shaft before you put it in the crank? The tighter the fit, the more critical it becomes to have the trans aligned so that it slides in with as little restriction as possible.

Pulling the trans in by using the bolts on the bell has some pitfalls. The biggest one is that, because you're farther from the center-line, a small change is amplified. This means that small changes in the gap are amplified in the angle between the shaft and bearing. Another is that the top bolts are not balanced with bolts directly opposite,

Let's go back and look at the gap, once again. Get the gap as close as possible before you actually try to pull the trans into place. Then run the bolts in until they just touch the bell. Now, starting with the top, use a torque wrench and draw the bolts up until you feel some increase in restriction. Draw the bottom in to the same torque and then go a little further, say 10#. Go back to the top and it should go to the same torque, +10, pretty easily. Go back and forth and, if there isn't something which is physically restricting the trans from sliding in, the torque shouldn't spike upward and should actually ease when things are lined up and the trans moves into the pilot bearing.

Slow and easy. If it binds in one direction, back off slightly and try giving the opposing bolts a tweak.

It's tough to troubleshoot long distance, and I know it's tough to know what suggestions to follow when you're on the receiving end of them. Your patience is admirable.

[David Jones]

I did trial fit the trans into the pilot. I had the trans installed, minus clutch and p/p, when I modified the trans tunnel.

I'm not going to use the bolts to pull the trans in.

I have to install the scattersheild to the transmission before I can install the hyd line to the slave. There is no way to thread and tighten the hyd line to the slave through the access hole in the side of the scattersheild. It has to be done through the front of the scattersheild. My plan is to lift the trans/scattersheild/hyd line combo into place (I did that last night) and then take the scattersheild off of the trans and slide it over to the engine and bolt it there. I'm only 1/2" out so I should be good there. Since I've got the hyd line installed already at that point I'm good there and there is enough give in the line I will be able to move the scattersheild off of the trans and on to the engine with no issues. Now I'll be able to move the transmission only (without the 20-30lb scattersheild attached) to possibly ease the install process of the input shaft into the pilot.

I would never use bolts to force the trans in.

[Stuckinda60s]

Your plan sounds like it would help make things easier.

I'm not talking about forcing things into place, I'm talking about easing them in. That's why you use a torque wrench, there's quite a difference. I've often had to use the method, without the torque wrench, to get the proper alignment. I'd alternately tighten and/or back off on the bolts and could feel the sweet spot when I found it.

You'll almost definitely have to use some force to draw things together, it's too much to expect it to just slip in.

[David Jones]

Originally Posted by Stuckinda60s

You'll almost definitely have to use some force to draw things together, it's too much to expect it to just slip in.

This begs the question.....

If it doesn't easily fall into place how will I KNOW the shaft has found the pilot bearing without me actually seeing it?

I'm assuming that the 1/2" I find myself stuck at is greater than the depth the input shaft seats into the pilot?

When I did the test fit without the clutch and p/p in place the trans did basically just slip in to the pilot easily. I'm sure adding the clutch splines to the equation complicates things?

[Stuckinda60s]

You've got to have a feel for it. You won't hurt anything with 20 or 30# of torque on it and that should put you in a place where you can feel changes when you back off.

Often, when you back off on one bolt, the opposite will then draw further in with less torque. That tells you you're going in the right direction. When the torque increases, you can go back to the side you had previously loosened and tighten it or loosen it some more.

You might have to use the jack to raise or lower things to help.

Whatever you do, use logic to determine where to raise, lower, tighten or loosen, remembering that you may have to do two things together to make it work.

There's quite a sigh of relief and sense of accomplishment when your patience is rewarded and you hit that spot. It's a definite YES!!!

[David Jones]

Thank you Rich.

Back under it in a few hours.......

[Grand73Am]

When mine wouldn't go that last 1/2", when I did finally line it up accurately enough, the shaft did slide in easily. Because the plastic alignment tool was useless, I used the transmission itself to line it up. Easier for me, since the body was off the frame. So, my opinion is that if it's really lined up, it doesn't take any extra force to make it go. You'll know it when it hits the sweet spot, since it will sink in and there won't be any question.