pressure plate experts

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That’s strange it isn’t painted. Where did you buy it? It’s hard to tell how deep your levers are in the case. Should be around .250”.
 
For the inner ends of levers to come towards the TOB, the outer ends have to be moving towards the flywheel.
This can theoretically only happen one of four ways
A) the cover is flexing, or
B) the disc is being compressed
C) The fulcrum saddles are moving.
D) the disc is not being flat to the flywheel,
A thru C should not be possible

Go back to the pic in post #3, looking at the flywheel side of the disc.It should be nearly flat back there so it doesn't hit the flywheel bolts. Check out how far that hub protrudes. See if it fits into the recess . Check the appearance of the tops of the flywheel bolts.See if the spline-hub moves in the disc.
 
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Disc is sitting flat for sure. The RAM guy said the pivot pins can be bent which makes a cam eccentric for the levers/fingers too. Which makes sense. When I get home I’ll investigate more. I probably should have just gone with a quality diaphragm clutch and eliminate any of this BS.
 
694spd said:
I'm interested in you problem and hopefully a known cause and solution to it.
I bought a stock replacement Ram #88766 B&B clutch from Summit last fall for my 340 Dart. I was only able to put about 150 miles before putting the car away for the winter. I did not notice any problems with it, but I have yet to put it under any real load.

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Looking at your PP, I don’t see a weight in any of those spring holes. I’ve never seen a Ram clutch that didn’t have a balance weight. I’m guessing that’s what it is. I’ve never seen a RAM unpainted. Where did you buy that?

Pic is from Rams Facebook page.

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Mopar92 said:
Looking at your PP, I don’t see a weight in any of those spring holes. I’ve never seen a Ram clutch that didn’t have a balance weight. I’m guessing that’s what it is. I’ve never seen a RAM unpainted. Where did you buy that?

Pic is from Rams Facebook page.

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If you look at the picture, you can see all the fingers are up against the cover because they are not bolted down with a disc. When you bolt the pressure plate to the flywheel, this levers will move away from the cover (towards the flywheel). And you will have a gap between the cover and the lever. The gap can vary for a number of reasons.

Disc thickness. The thicker the disc the lower the finger height (fingers closer to the flywheel). If you start with a thinner disc than what the pressure plate was set up for, the fingers will be closer to the cover.

Disc wear. As the disc wears and gets thinner, the fingers move up towards the cover. This is why guys who abuse the clutch or ride the pedal will LOOSE freeplay quicker than guys who don't do either (I've known some who do both).

Been a while since I used a B&B cover, but *IIRC* the fingers can move back towards the cover when you are just sitting there. Again *IIRC* those plates either had 3 roller assist or 6 roller assist (let's hope it ain't a 6 roller cover...I don't *THINK* you need all the extra counterweight).

As the flywheel starts to rotate, those rollers are forced out to the cover. Sitting there those rollers move away from the cover and let the finger move up and down a bit. As RPM's go up and the rollers go to the outside of the lever on the cover side, they wedge between the cover and the lever. That adds some counter weight to your plate load. While the clutch is rotating, the finger can only move a very small amount once the roller gets into place. Then the finger height won't change. As RPM increases, those three rollers actually load the fingers more and add plate load.

I use a B&B pressure plate with Long style fingers. When my plate is bolted down the levers have some movement in them. I aways check my free play with the engine running at idle. My counter weights are bolted to the lever, where the B&B weights are not adjustable. That way the finger height is where it will be when the car is moving. I go for 1/2-3/4 inch of free play with the engine at idle. This will give me 3/4-1 inch when the engine is off.

My point of all this is I don't think you have a problem.

Back in the day, we ran a thicker disc, which lowered the finger height. Then we would raise the finger height back to where it should be with the thinner disc and then raise the finger height another .100 and you could shift at 7000 RPM with very little pedal.

Hope this helps.
 
yellow rose said:
If you look at the picture, you can see all the fingers are up against the cover because they are not bolted down with a disc. When you bolt the pressure plate to the flywheel, this levers will move away from the cover (towards the flywheel). And you will have a gap between the cover and the lever. The gap can vary for a number of reasons.

Disc thickness. The thicker the disc the lower the finger height (fingers closer to the flywheel). If you start with a thinner disc than what the pressure plate was set up for, the fingers will be closer to the cover.

Disc wear. As the disc wears and gets thinner, the fingers move up towards the cover. This is why guys who abuse the clutch or ride the pedal will LOOSE freeplay quicker than guys who don't do either (I've known some who do both).

Been a while since I used a B&B cover, but *IIRC* the fingers can move back towards the cover when you are just sitting there. Again *IIRC* those plates either had 3 roller assist or 6 roller assist (let's hope it ain't a 6 roller cover...I don't *THINK* you need all the extra counterweight).

As the flywheel starts to rotate, those rollers are forced out to the cover. Sitting there those rollers move away from the cover and let the finger move up and down a bit. As RPM's go up and the rollers go to the outside of the lever on the cover side, they wedge between the cover and the lever. That adds some counter weight to your plate load. While the clutch is rotating, the finger can only move a very small amount once the roller gets into place. Then the finger height won't change. As RPM increases, those three rollers actually load the fingers more and add plate load.

I use a B&B pressure plate with Long style fingers. When my plate is bolted down the levers have some movement in them. I aways check my free play with the engine running at idle. My counter weights are bolted to the lever, where the B&B weights are not adjustable. That way the finger height is where it will be when the car is moving. I go for 1/2-3/4 inch of free play with the engine at idle. This will give me 3/4-1 inch when the engine is off.

My point of all this is I don't think you have a problem.

Back in the day, we ran a thicker disc, which lowered the finger height. Then we would raise the finger height back to where it should be with the thinner disc and then raise the finger height another .100 and you could shift at 7000 RPM with very little pedal.

Hope this helps.
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I appreciate the reply. I do. But I have a problem. With 1/2” + TO bearing clearance the clutch has maybe 3” of travel and you can feel it pushing the clutch against the predal stop over 3000. It will push the pedal up 3” easy by itself. The fingers are moving a metric ton. It’s already killing my TO bearing.
 
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Mopar92 said:
I appreciate the reply. I do. But I have a problem. With 1/2” + TO bearing clearance the clutch has maybe 3” of travel and you can feel it pushing the clutch against the predal stop over 3000. It will push the pedal up 3” easy by itself. The fingers are moving a metric ton. It’s already killing my TO bearing.
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Then that's an issue. The B&B pressure plate has been around a long time. **** happens but damn, how did that get screwed up? Training a new guy?

Some things are inexplicable and this may be one of them. Somebody screwed up. They need to fix it for you.
 
I’m not sure. We will know when we pull it. They are very good communicating. No issues with them at all.
 
I stopped at local long time in business clutch shop yesterday and mentioned the issue of the clutch fingers moving back and coming into contact with the TO bearing at 3000 rpm. The owner quickly told me that can happen if the finger anti-rattle springs are weak.
OK, I'm just putting that option out there.
Lets hear some opinions on that possible root cause.
 
Not sure it/they can get beyond the cover unless something else is broke, missing, or out of adjustment. That said I'd imagine centrifugal force can swing it/them out to the point seen in this cover if the cover or components have issues. They do hang out a bunch. However, if this cover and flywheel has a disc bolted down in between, the three fingers would be depressed.
After that what else is there that can affect the peddle travel?
Maybe some engine/trans assembly roll as rpm is increased?
How about the crank moving rearward with rpm due to a worn thrust bearing?

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I posted in my thread but this thread was going as well. I’ll post on the other thread too but I got the car on the lift today. Changed the trans fluid and left the bell a little messy. Sorry. Anyway. I have .055” air gap, 2.5” pedal play and .260” of throw out bearing clearance. Video is in slow motion HD. Extremely annoying with the pedal play but it allowed me to diagnose this problem. It’s terrible feeling to drive. Anyway. I’ve got .600” or finger travel. It’s cooked the throw out bearing. Not even sure where to start besides pull it and send it to RAM.

 
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IMO, Top picture looks awful close from the get go to me. Hard to tell for sure.
16 seconds in the release bearing is not back to where it started from it appears to me.
Without the engine running, is the release bearing contacting all three fingers at the same time? If so the plate may not be the issue. If not the plate is likely damaged or out of adjustment.
The air gap doesn't have to be 0.060". It's a starting point to adjust up to.
Maybe try this.....
Back that adjustment off until the over center spring no longer pulls the pedal up. Start adjusting until the pedal pops up. Start checking for a gap. Adjust into it enough to release the plate.
 
I think I already told you I think there is something seriously wrong with this pressure plate PERIOD. Wrong parts, made wrong, something. I would be looking for an alternative.
 
67Dart273 said:
I think I already told you I think there is something seriously wrong with this pressure plate PERIOD. Wrong parts, made wrong, something. I would be looking for an alternative.
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I believe you. I’m gonna pull the mess out next week. I just wanted to share the video. As for the bearing clearance I stacked feeler gauges and posted it above in my reply. Stranger things have happened.
 
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