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[janbanan]

I've never had a failure with the stock piston. We currently run 3 cars over 600 hp with them, in fact 2 have well over 800 hp. If the stack up is correct put it together.
Doug

Rear clutch discs were totally burned and because of that I´m looking extra carefully on these parts.On this forum they say late style piston is a little taller. I have bought late style piston 2 times on Ebay but both times postoffice messed it up.I would appreciate if you could look at my film and tell me if this is ok or not.
https://youtu.be/WMDsKnJWw28

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I've never had a failure with the stock piston. We currently run 3 cars over 600 hp with them, in fact 2 have well over 800 hp. If the stack up is correct put it together.
Doug

[video]https://youtu.be/WMDsKnJWw28[/video]

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Sorry I´m a noob on Internetforums

 

[dvw]

Does the movement I'm seeing come from the waved snap ring being compressed or is it loose. I don't have an input shaft here that is not in a trans. I did measure parts that are laying around. The early pistons are .780"-785" thick. when the belleville springs are laid on the bench flat and measured .280"-.285" or .330"-.340". The rear clutch is applied immediately when the trans is shifted into any forward gear, so none of the components are ever spinning when it's being applied. Failure at that clutch only comes from #1 to much travel from melted spacer #2 cut/worn piston seals #3 small sealing rings on the input being worn/broken. The inner surface of the stator support where the rings ride is worn. This clutch can be set tight, .025-.030". The piston can't move very far. One last thought. My race car has an aluminum clutch retainer. Last year the expanded splines on the inner hub ate into the clutch retainer causing it to cock on the inner hub blowing out the piston seal. I've never seen a steel one do this but it's worth a look.
Doug

 

[janbanan]

Does the movement I'm seeing come from the waved snap ring being compressed or is it loose. I don't have an input shaft here that is not in a trans. I did measure parts that are laying around. The early pistons are .780"-785" thick. when the belleville springs are laid on the bench flat and measured .280"-.285" or .330"-.340". The rear clutch is applied immediately when the trans is shifted into any forward gear, so none of the components are ever spinning when it's being applied. Failure at that clutch only comes from #1 to much travel from melted spacer #2 cut/worn piston seals #3 small sealing rings on the input being worn/broken. The inner surface of the stator support where the rings ride is worn. This clutch can be set tight, .025-.030". The piston can't move very far. One last thought. My race car has an aluminum clutch retainer. Last year the expanded splines on the inner hub ate into the clutch retainer causing it to cock on the inner hub blowing out the piston seal. I've never seen a steel one do this but it's worth a look.
Doug

My piston and belleville have exactly the same measerments as yours.I´m holding belleville as far as it goes with my thumbs and I have this play between belleville and piston.I had some slippage for a while and got pissed of that and gave it all on first gear and that was it.(not so intelligent)
When I took it apart discs was burned, plastic sealing in pieces, belleville cracked. I also found a snap ring in pieces, but there wasn´t any missing?Piston sealing was strange because it was in plastic.A plastic ring with an opening, it had also pieces missing.Could it be belleville cracked, piston went out to far and broke the sealer and piston sealing on the way back?

 

[dvw]

I believe you have dignosed your issue exactly. Put a steel ring in it, new piston seals, and snap ring. Set the clutch clearance and you'll be ok. Air check both clutches by setting them in the pump. Air up the holes at the edge of the pump and you'll hear the clutches thud. There should not be a lot of air hissing.
Doug

 

[janbanan]

I believe you have dignosed your issue exactly. Put a steel ring in it, new piston seals, and snap ring. Set the clutch clearance and you'll be ok. Air check both clutches by setting them in the pump. Air up the holes at the edge of the pump and you'll hear the clutches thud. There should not be a lot of air hissing.
Doug

Thanks a lot for your help. I have tryied to find a steelspacer, do you know where to find one? Maybe I can mill one myself? If plastic is ok it must work with mild steel?

 

[dvw]

I've used the plastic ones. I personally think they only melt when the clutches start to slip. If the seals, rings, and stator support are in good shape you should be fine.
Doug