727 play

[janbanan]

Hi, i´m from sweden so my english is not perfect.
I have overhauled my 727 transmission and everything looks alright. There is one thing bothering me though.
When i assembly rear clutch there was a play between piston and belleville spring. I have nylon spacer and waved spring in place.
My thinking was, when oilpressure occurs this will push the piston forward a little bit and it will stay there when it touches belleville spring. I´m not talking about discplay, they have recommended play. If anyone have experience of this I would appreciate some help.

 

[dvw]

There are 2 different style pistons and springs. They must be used as a matched set.You need to swap the spring or the piston. This will help you.
http://board.moparts.org/ubbthreads...2/re-huge-frustration-again-727-problems.html
Doug

 

[janbanan]

There are 2 different style pistons and springs. They must be used as a matched set.You need to swap the spring or the piston. This will help you.
http://board.moparts.org/ubbthreads...2/re-huge-frustration-again-727-problems.html
Doug

Thanks a lot! It seems like I need a late style piston combined with my old style belleville to bring clearance as low as .003-.010.
It´s very difficult finding the right parts here in Sweden, could you give me a hint where to look? I have been looking for the steelspacer for some time now.

 

[badlite]

A&A transmission should be able to help you out.

 

[dvw]

Thanks a lot! It seems like I need a late style piston combined with my old style belleville to bring clearance as low as .003-.010.
It´s very difficult finding the right parts here in Sweden, could you give me a hint where to look? I have been looking for the steelspacer for some time now.

No, the piston and spring match. Post a picture of what you have . I may have what you need.
Doug

 

[Kern Dog]

Your English is far better than a few of the toothless idiots that pollute some of the web forums that I have frequented. The majority are great, but there are some morons that REALLY make you wonder!

 

[janbanan]

No, the piston and spring match. Post a picture of what you have . I may have what you need.
Doug

I looked at the forumpost you suggested and there was a comment from what seemed to be a professional mechanic about using late style piston with early style belleville. They could be combined and you could get better clearenceplay because late style piston was thicker.(And he always did!)
I have mounted my transmission together but I will tear it down again because of this.I will send you a picture as soon as I have done that. I think it is originalparts in there(4 discs).Is it possible to have a spacer in there?

 

[Scooby67]

Your English is far better than a few of the toothless idiots that pollute some of the web forums that I have frequented. The majority are great, but there are some morons that REALLY make you wonder!

I totally agree!!

 

[janbanan]

No, the piston and spring match. Post a picture of what you have . I may have what you need.
Doug

I found a picture in my phone but it is before I installed discs. What happened was all discs totaly burned out,belleville cracked, plastic sealer in pieces and a thin (extra?)snapring in pieces was found at the bottom of case. Maybe the "extra" snapring was used as a spacer and also a very bad idea?

 

[dvw]

Go back to the Moparts post I attached. You will find the 2 springs do not look the same. My bet is the replacement spring you used is the different than the original. Early spring (73 earlier) is used with early piston, Late spring (74 later) with late piston. The last 2 digits of the year the piston was cast will be on the piston.
Doug

 

[janbanan]

Go back to the Moparts post I attached. You will find the 2 springs do not look the same. My bet is the replacement spring you used is the different than the original. Early spring (73 earlier) is used with early piston, Late spring (74 later) with late piston. The last 2 digits of the year the piston was cast will be on the piston.
Doug

Sorry , but that is not true. Yes you can use the late piston with and early spring. I do it all the time. Even Chrysler in 2000 went back to the early style belleville spring on all the 46REs / 48REs transmissions. When useing a #374 late stlye piston with an early Belleville spring you can set the clearance between the piston and the spring down to .003 - .010, then set the clutch pack clearance at .030-.035 , this will keep the piston from coming out too far and still apply the clutches fully

This is a comment from CRT (Cope Racing Transmissions) in that post you attached.
I´m shure I have the early belleville. I will take transmission apart this evening again.... and measure piston.I have also bought 46RE/48RE piston on ebay but I still haven´t found steelring instead of plastic.I will take a picture and I´m really thankful for your help. I´m used to work with Harleys but I have no experience of automatic transmissions so I need all the help I can get.

 

[janbanan]

If I push belleville to the bottom of retainer I have about .078 in play and that is far to much I guess.A thicker piston would fix it...or I could mill the seating for belleville down and try to find a thicker sealing.Another strange thing was that pistonsealing was in plastic,not rubber, and it was broken.Yes I know I should have checked this earlier, but I told you,I know nothing about transmissions.

 

[dvw]

Sorry , but that is not true. Yes you can use the late piston with and early spring. I do it all the time. Even Chrysler in 2000 went back to the early style belleville spring on all the 46REs / 48REs transmissions. When useing a #374 late stlye piston with an early Belleville spring you can set the clearance between the piston and the spring down to .003 - .010, then set the clutch pack clearance at .030-.035 , this will keep the piston from coming out too far and still apply the clutches fully

This is a comment from CRT (Cope Racing Transmissions) in that post you attached.
I´m shure I have the early belleville. I will take transmission apart this evening again.... and measure piston.I have also bought 46RE/48RE piston on ebay but I still haven´t found steelring instead of plastic.I will take a picture and I´m really thankful for your help. I´m used to work with Harleys but I have no experience of automatic transmissions so I need all the help I can get.

what about the early piston with a late spring? I believe that is what he has causing the extra clearance
Doug

 

[janbanan]

No, I have early piston and early spring and that is the right combination, but it seems like it is possible to replace early piston to a later one(74 and up).
Later piston are supposed to be a little thicker. I have bought one on ebay but seller did something wrong with adresslabel. My son lives in Brooklyn New York, is there a shop nearby so he can bring one to sweden for christmas?

 

[dvw]

How much play are we talking about? When the combo is wrong there is quite a bit of play. If the parts are assembled in the wrong order there is quite a bit of play. Otherwise there should be very little play.
Doug

 

[janbanan]

How much play are we talking about? When the combo is wrong there is quite a bit of play. If the parts are assembled in the wrong order there is quite a bit of play. Otherwise there should be very little play.
Doug

I have about 0.078. Piston is marked 72 and I have early style belleville. I don´t understand why they doesn´t match up better, could it be I have a later retainer?

 

[dvw]

Your picture in post #12 is a early spring with an early 72 piston. Do you have the stack up correct? Piston, spring, spacer, wavy snap ring?
Doug

 

[janbanan]

Yes I have the correct parts there, the thing is if I push piston to the bottom of retainer and also push belleville to the bottom of seating I have this play.(.078)
I can see some scratches on the "backside" of piston, could it be to thin? (It is 19.9 mm, that would be about 0.78 inch.)

 

[janbanan]

A&A transmission should be able to help you out.

Maybe you solved it for me, I saw this in their catalog

 

[dvw]

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