*Pics Attached* Need help SM465 throw out bearing distance.

[handloader90]

I just mated a SM465 to a LQ4 (LS 6.0).

I've used the correct flywheel for the 4.8/6.0 LS engine.

I've used the correct clutch disc, pressure plate and throwout bearing for a SM465.

I'm using the Novak hydraulic clutch retrofit kit. It comes with it's own clutch fork which differs from the stock mechanical clutch fork thatwas previously installed.

I've got everything bolted up now and I'm ready to throw it all in my K5 but I want to make sure that the throwout bearing is where it needs to be.

In the pics below the throw out bearing is touching the fingers on the pressure plate (I have the diaphragm style with a lot of fingers not the one with just 3 fingers).

There is about 3/8" of space between the clutch fork and the back portion of the clutch fork opening, so the clutch fork should be able to push the throwout bearing into the pressure plate fingers 3/8" before the clutch fork is stopped.

Is the enough to disengage the clutch properly?

Just wanna make sure before I put everything in the truck... don't wanna fire this thing up and it doesn't move then I have to pull everything out.

@bent72
@campfire

 

[Bent77]

You worried the back of the fork will contact the bell housing before the plate is actuated?

Looks to be close, I don't recall how much is needed to get the fingers compressed. That and I'm not sure how you would change anything besides grinding the bell. Seems that would be mentioned in Novaks instructions?

 

[campfire]

You worried the back of the fork will contact the bell housing before the plate is actuated?

Looks to be close, I don't recall how much is needed to get the fingers compressed. That and I'm not sure how you would change anything besides grinding the bell. Seems that would be mentioned in Novaks instructions?

You would adjust that by changing the length of the pivot, no?

 

[Bent77]

You would adjust that by changing the length of the pivot, no?

That's all I could think. Was just pondering if there was different lengths so as to swap one out for another. Not a huge fan of a bunch o washers on something like that.

@handloader90 how well does the slave rod line up to the fork ?
Seem close or too much slack?

 

[handloader90]

I'm just not sure what the clearances should be, how far away from the pressure plate fingers should the throwout bearing sit at "rest"?

I'm also not sure how much the pressure plate fingers have to be depressed to release the clutch disc.

 

[campfire]

FWIW, mine also looked kinda close but did not have any issues. I shoved the rubber boot in there right away, so I'm not even sure what it would have looked like. But it was closer to the back end than the front.

 

[campfire]

I'm also not sure how much the pressure plate fingers have to be depressed to release the clutch disc.

Not much. You would have seen them travel through their full range of motion when you bolted the pressure plate on. My diaphram moved about 1/2" from full compression to full extension.

 

[campfire]

Travel at the slave cylinder was somewhere around an inch.

Again, I didn't take actual measurements of any of this, I just put pieces together in the factory configuration. I did it several times before I figured out that my S/C was bottoming out and failing to properly engage the clutch. So if anything my pivot arm is further back than it should be. Still no contact with the bell housing.

 

[handloader90]

With the pushrod installed into the slave and clutch fork and the return spring attached to the clutch fork the pushrod is straight.

With all of that stuff installed there is more distance between the pressure plate and throwout bearing, looks to be roughly 1/2" between the two.

 

[handloader90]

Not much. You would have seen them travel through their full range of motion when you bolted the pressure plate on. My diaphram moved about 1/2" from full compression to full extension.

So about half of that is what it would take to disengage the clutch disc right? About 1/4"?

I've never worked on a manual before so I don't know. Been searching google for awhile now and theres talk about different length throwout bearings. I'm pretty sure I have the long one from the pics I've looked at.

 

[handloader90]

You worried the back of the fork will contact the bell housing before the plate is actuated?

Kinda... I'm not sure if that is enough space to disengage the clutch.

 

[campfire]

With the pushrod installed into the slave and clutch fork and the return spring attached to the clutch fork the pushrod is straight.

With all of that stuff installed there is more distance between the pressure plate and throwout bearing, looks to be roughly 1/2" between the two.

View attachment 223166

View attachment 223167

Yeah, I wasn't ever able to see inside the bell housing due to the rubber plug.

 

[Bent77]

If it only pushes an inch at the slave, move the fork mechanically with some leverage and see what an inch of travel looks like

 

[Bent77]

I think interfering is more of an issue than engaging, but hard to tell not being there.

I'd measure the travel at the fork on mine if I had a helper that wasn't in a diaper

 

[handloader90]

If it only pushes an inch at the slave, move the fork mechanically with some leverage and see what an inch of travel looks like

Tryingto think of how to do that... I tried by hand and that sure as hell didn't work lol.

If I am able to manually engage the clutch fork enough the disengage the clutch disc then the mainshaft of the SM465 should spin if I were to spin the harmonic balancer on the engine, right?

 

[handloader90]

This is the best I could come up with.

 

[campfire]

Can you rotate the output shaft with your hand?

(while in gear, of course)

 

[campfire]

That is so far back that it doesn't look inline with the S/C anymore. I sure hope that you've accomplished disengagement by that point...

 

[handloader90]

So, with the ratchet strap pulling the clutch fork as far back as it would go I put the transmission into gear (I thing 3rd, not that it really matters) and I stuck something into the splined trans/t-case coupler that's in the adapter.

Turned the harmonic balance on the engine by hand and the item in the coupler spun.

Problem is I took off the ratchet strap so the throwout bearing wasn't engaging the pressure plate at all and Spun the harmonic balancer, the item in the couple span too.

Maybe I'm confusing myself?

 

[campfire]

So, with the ratchet strap pulling the clutch fork as far back as it would go I put the transmission into gear (I thing 3rd, not that it really matters) and I stuck something into the splined trans/t-case coupler that's in the adapter.

Turned the harmonic balance on the engine by hand and the item in the coupler spun.

Problem is I took off the ratchet strap so the throwout bearing wasn't engaging the pressure plate at all and Spun the harmonic balancer, the item in the couple span too.

Maybe I'm confusing myself?

When the strap is tight you should be able to rotate the output shaft with your hand (no tools), without also rotating the engine. If you're rotating the engine and finding that the output shaft (connected to nothing) is also spinning, that may or may not mean anything. What you care about is how much drag is on that clutch disc. If the clutch is dragging enough to be trying to spin the engine, you will not be able to turn it by hand.