Mike44138

iTrader: (3)

Well looks like my LS6 clutch swap didn't go as well as I thought it did. About 2 weeks ago started leaking clutch fluid from the slave cylinder. Just dropped the transmission and there is a crack on the inside of the slave cylinder. There is also obvious wear from the input shaft contacting the slave cylinder and griding metal off. The slave bolts were tight when I removed it and a visual inspection of the input shaft doesn't show any excessive wobbling and it doesn't appear bent. Anyone have any similar experiences or suggestions on what could be causing the input shaft to contact that inside of the slave cylinder?

BTW: The pilot bearing, flywheel, clutch plate and pressure plate were replaced and balanced in August.

Thanks,
Mike

P Mack

iTrader: (6)

I found the same thing when i pulled my engine & tranny for the shortblock swap. I have no idea what caused it but i'm curious too.

Farmer2

iTrader: (168)

Could it be that maybe the slave got so hot that it expanded and went into the input? and thats what caused the cracking too?

Just a shot

P Mack

iTrader: (6)

If the slave expanded, the inner diameter would grow too, making it farther from the input shaft. I think the slave has to be wobbling somehow.

kidkl

How did the pilot bearing look? Also did you notice alot of movement on the input shaft?

Mike44138

iTrader: (3)

The pilot bearing appears to be in good condition. I can't see any difference from when I put it in back in August and the bearing appears to roll smoothly. The input shaft has no end play and the only way I can tell it's got any movement side to side is by feel. Visually it's imperceptible. I don't know from experience if this is excessive, but it doesn't feel like it could get much tighter.

I'm thinking this could be an input shaft to crank shaft alignment problem?? Maybe like the bellhousing needs to be indexed? or maybe the input shaft has more movement than I know about when it's at high RPM due to something like a worn input shaft bearing??

I took a few pics with my cellphone for everyone to take a look at.

Thanks for all the help.

Farmer2

iTrader: (168)

Is it possable that the slave was mounted not mated flat to the trans?
or maybe the slave is defective and favors one side sideways like. Put the slave back on and see if it favors the grinding.

Interesting to say the least

Mike44138

iTrader: (3)

This is actually the 2nd slave I've put on the trans in 6 months. I thought the first one could have been defective or damaged on installation, but after it's blown this one up I think there's a problem elsewhere. I'm pretty positive that the slave was mounted flush because I remember turning the input shaft after it was mounted to check for any rubbing or binidng. I've got a new slave on the trans now and I just tried turning the shaft while pulling/pushing on it to see if I could get it to contact the shaft. No contact no matter how hard I pushed/pulled and rotated the shaft. I'm really at a loss on this one....

Farmer2

iTrader: (168)

With the new one on, does it look centered on the input shaft?
You would have had to feel a hellasous vibration for that to happen if something were out of balance.

Mike44138

iTrader: (3)

The slave looks centered perfectly. I did just take a look at the end of the crank and there is actually a wear pattern that looks like the input shaft is sitting slightly low and left. The end of the input shaft has left a circle on the end of the crank and I can see that it's not centered very well. Anyone have any idea if there's a procedure to check/align the transmission to the crank?

calhoon

iTrader: (6)

thats the job of the bell dowells and the pilot bearing. One of these is not working. I suspect the pilot is bad( and has been the cause of your first CSC damage) I assume you have the original bell. Is is damaged? (cracked?)

Mike44138

iTrader: (3)

I had a feeling the bellhousing could have been cracked or dammaged some other way so I took it off last night. After cleaning it up there doesn't appear to be any cracks that I can see and the dowels appear to be fully seated and in decent shape. I was thinking the bellhousing could possibly be bent but with the aluminum it's made out of I would expect it to crack if that were the case. Other thought I had is that it might have a hairline crack that I can't see.... I was also just thinking about the fact that the inside of the slave was worn around the whole diameter, but just worse at the crack location. To me I would think that means the input shaft is floating around quite a bit to be able to make contact with the slave cylinder in all areas. I'm going to replace the pilot bearing just to be sure, but this was a new pilot bearing when I did the fix in August.

Ugh.... this just sucks. Again thanks to all for the help.

calhoon

iTrader: (6)

Did you have trouble aligning the box when it went in? It is quite posible to damage the pilot bearing on an install. Always pullin up evenly and if its going on tight , its not aligned.

Mike44138

iTrader: (3)

No more trouble than would be expected. There was the typical messing with the output to get the splines aligned, and a little bit of manuevering to get it in place. Looking at the bearing I removed today I don't really see any signs of damage although I'm wondering if I had it seated all the way in the crank.When I installed the bearing today I'd say it's recessed about 1/16th into the crank, think this is enough or should it sit deeper?

I've got the trans at a shop now, I told them to replace the input shaft bearings just to be safe. After talking to the guys over there none of them had much of an idea. The only thing thrown out was that it looked like an alignment problem, or that the pressure plate was pressing against the slave unevenly.

Mike44138

iTrader: (3)

Update:

Just saw two other threads that could apply:
https://ls1tech.com/forums/manual-transmission/428548-just-installed-textralia-possible-blown-slave-cylinder-have.html
https://ls1tech.com/forums/showthrea...ht=blown+slave

oange ss

iTrader: (50)

i'm goin with a bearing problem, the pilot bearing and the input shaft bearing are the only things that support the front of the main shaft

oange ss

iTrader: (50)

if the damage seems more rearward on the slave, i'd look into a bad front bearing or race

sgarnett

iTrader: (1)

FWIW, the first time I got a new clutch I ordered a GM TO bearing because I didn't know they came on the slave anyway. That TO bearing, which has never been used, is crooked just like yours (not quite as bad, but close). I don't know if a defective TO bearing could cause enough side load to distort and crack the slave or not, but FYI....

calhoon

iTrader: (6)

The throw out bearing does have enough free play that you can skew it when not installed so I would not assume that new one is bad just because it is in a skewed position. That would straghten up with the install. The only other item is the installation of the slave. Check its mounting surface and its pilot dia on the trans. It is possible that you somehow got the slave on cocked ant installed taht way. Look for a reason/ evidence that the slave did not seat square to the trans front adapter plate.

sgarnett

iTrader: (1)

The skewed TO bearing is quite firmly skewed, like something wasn't lined up right when it was pressed together. It's nothing like the free play in a good one. I recently compared it to two other brand new slave/TO assemblies.

One of the new GM slaves (the one that came with the Textralia, I think) had a sticker on the mounting surface that I had to remove and clean with Goo-Gone. That would prevent it from seating squarely if not removed befopre installation.