Input Drum Question

[TYTILIDIE]

On the inner wall of my input drum, it is rough looking. I vaguely remember it being like this before but it was 2 years ago so I thought Ild ask. It is smooth where its supposed to be down where the bottom pressure plate goes but up towards the top it is rough. Also havent found any real toasty looking clutches so am now starting to wonder what is causing my slipage. In the top of the assembled input drum on the walls are the what I call the 2-pack springs. I dont knwo what they are realy called but one of those was broken but cant imagine that being much of a big deal.

Mike

 

[jwaller]

Re: Input Drum Question

leave those out. and ya the nonmachined surfaces of the drum are not important. you might have a leak at the shaft to drum joint. you should wet air check that for leaks.

 

[TYTILIDIE]

Re: Input Drum Question

Leave the "2-pack" springs out? Why? What do they do? How do I wet air check those? I CAN hear a check ball rolling around in there too.

Mike

 

[nightdiver]

Re: Input Drum Question

These springs are responsible for many 3-4 clutch failures . NEVER USE THEM.
These springs are the extra piston return help.
The litlle check ball is in a hole next to the shaft. Weld that one or put some JB weld from the inside.
Use the blue clutches, they are the best stock replacement

 

[TYTILIDIE]

Re: Input Drum Question

Actually I bought this thing from a SY guy here in town called the "ZPACK". Why weld the check ball? I took it to that guy today and he put grease on it.

Mike

 

[nightdiver]

Re: Input Drum Question

Ooops no email for this post.

This little valve is there to get rid of the air in the system BUT there is some great oil pressure loss/leak from there. With a loose TC things gets worse and we got to find ways to save leaks

 

[nightdiver]

Re: Input Drum Question

http://www.raybestospowertrain.com/prod_features_zpak.html

I dont know anyone that used these clutches.....does anyone ?

 

[jwaller]

Re: Input Drum Question

zpack's are not as good as the blue's. spoken from a raybestos engineer. if oyu do some searching this topic came up when they first came out. I posted the original email from the engineer and you can read about it yourself.

 

[TYTILIDIE]

Re: Input Drum Question

Well that sucks to hear. I will definately check that out. Still havent gotten the overrun section done so am not quite to that point yet. For whatever reason the stack up is 7/16" higher than it should be when its all assembled. So basically cant get the retaining ring in. Im not sure what the hell is going on with it but Ive had it apart atleast 6 times. It seems like the shaft is to high but its all one piece so I dont really know but its driving me nuts. I didnt have any problems putting this thing together last time. Oh well.

Mike

 

[Crimson93Ty]

Re: Input Drum Question

I spoke to raybestos about the z-pak. They hold up really well. Greater coefficient of friction than the typical BW hi energies and basically another plate is added. The blues were intended for one market and the z-pak was intended for another. Blues being mainly for racing and the z-pak being for heavy duty/occassional racing apps. Being that most just race their truck occassionally, the z-pak is a good alternative to stock friction replacements. The only drawback is you have to use a #7 apply ring. The legs are shorter. It should've been in the instructions. I've used them in several transmissions I've built and the apply is really good and they've put many many miles on them without change in shift feel.

There is a ball in cup deal on the shoulder of the drum. That is the one they probably put grease on to help it seal. The one they are talking about sealing is kinda down inside the pocket a bit off to one side. It is a tiny hole. Just JB weld it up. Don't seal the one under the selective backing plate. You need that one to lube the torrington.

The 2 spring return deals(5 of them in all) should be deleted. Those have different calibrations depending on clutch stackup. GM has several different part numbers for them. What they are supposed to do is help push off the 3-4 clutch pack when you do a 3-2 shift. Unfortunately, if they break or are not calibrated correctly for the clutch stack you have, they can damage the pack. Best bet is to just remove them and then enlarge the #44 hole(3-2 hi speed release) to .093" and forget about it.

I've also used the sonnax 3rd accumulator check valve assembly and am also very happy with it. Give's a really good clean apply and release if you do anything with the 3rd feed.

If you are 7/16" off, my bet is that you put the 3-4 return spring assembly on the wrong side of the apply ring. The piston should go in, then the apply ring, and then the return spring assembly on top of it.

Take care.

 

[TYTILIDIE]

Re: Input Drum Question

Actually I found out today that I am retarted and put the sprag unit together wrong. I have already installed the ZPACK but it said nothing baout enlarging any holes. Is this a must or what? If so, Im not sure what holes or hole you are talking about. Also didnt JB weld anything. I have heard nothing baout htis. Is all this a necessity? I hate to have to take this damn thing back apart but if i have to then I will. Thanks for all the good info btw everyone.

Mike

 

[Crimson93Ty]

Re: Input Drum Question

Rebuild Guide
Look on page 7.
You need to get an ATSG rebuild book. Most of the stuff we are talking about is in there. ESPECIALLY if it is your first time building one. Don't take the whole input drum apart to do the epoxy deal if you've got it together and air checked everything. You know how to air check the input drum? Don't just use the Haynes manuals. They have good pics but not a lot of detail like the ATSG has. There are lots of other little tricks builders on here know as well. 700 had a lot of problems. When guys do rebuilds, they try to address these if they are building their own.

 

[nightdiver]

Re: Input Drum Question

but it said nothing baout enlarging any holes

He is talking about the seperator plate. Do your homework and read the manuals. Everything will be more clear then.
There are a lot of mods that can be done here , but you dont need them if you got a stock engine. All you need is a good rebuild(syty builder) and blue clutches

 

[TYTILIDIE]

Re: Input Drum Question

Im just going to stick with what I GOT FOR now. I talked to a guy yesturday who says he uses the ZPACK in his SY (nice one btw) and has had no problems with it. Where can I get the ATSG manua? I do have the Hanes and this is my 2nd trans rebuild. I did notice that it doesnt really explain much nad the pics ar so so quality. I get the basic idea of how the trans works but the struff you guys allknow is what I really want to learn. I hatge having to ask these questions all the time and its even worse when I have to ask a a builder who is not getting paid for giving me info. I usually slip a 10 or 20 though. I would like to get my hands on a core SYTY trans to work on in my spare time and get all the good stuff for. I just cant afford it right now unfortunately. Hopefully Ill be ok with Ive got for now. My motor is stock and the turbo has the GT30 wheel (Waller built) in it.

Mike

Mike

 

[Crimson93Ty]

Re: Input Drum Question

Follow the guide and do the pressure regulator valve mod in the pump so you get better lube during lockup. Check the bushings and make sure they have no gouges in them. Keep the check ball in the end of the input shaft and don't enlarge any of the feeds on the separator plate. Use an 093 servo(corvette) servo not the billet servo. There is one valve you should block. It's called a line bias valve. line bias valve
It explains how to do it at the top.
This will help keep the band from burning up at WOT for extended periods.
Keep your 2nd accumulator and 3rd accumulator in the servo intact. Your 4th accumulator in the case, needs to be tapped and blocked. I've used 1/4 20 tap and a small allen bolt to block it with blue loctite on it. The 4th accumulator passage continues to the piston and then GM put a bleed in the case on it. So your 4th oil just gets dumped into the case and it runs down in the pan. Don't want that.
Everything else should be straight forward. Make sure your sprag rotates in the right direction. Also make sure the low roller clutch is installed correctly. It can be installed backwards, I've seen it.
Have someone with a dial indicator set your endplay for you. .005" to .015" is what I usually shot for. You should definitely use a beast sun gear shell. They only run like $55 and they will not break like the stock shell will.

 

[TYTILIDIE]

Re: Input Drum Question

The 4th accumulator passage continues to the piston and then GM put a bleed in the case on it. So your 4th oil just gets dumped into the case and it runs down in the pan


This wouldnt be a check ball in a bullet type thing would it? I jsut bought a new one today.

Mike