Transaxle Input Shaft End Play?

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Fellow Duners or @Sean@Weddle?

Help I'm in panic mode 😀. I lost an entire season last year waiting on the R&P and I was hoping for an easy & quick fix.

How much end play should I expect on the input shaft of my PBS sequential? I just got back from my shakedown weekend after the transaxle was completely freshened up including a new R&P. During my clean  up I found gear oil dripping from the bell-housing. Car was shifting perfectly with no noticeable noise or whine. I just pulled the motor hoping to simply find a bad shaft seal, its definitely leaking from the seal but the shaft also seems a bit sloppy.  Did something internally kill the seal? Thanks in advance for your help and insight. Tim


20221024_220652.mp4

 












 

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replace the pilot bearings, that keeps it from moving, 


Do what @J Alpersuggested and while your there replace the input shaft seal and TO bearing. 
I'll have to dig out my invoice from the re-build... I believe the pilot bearings were just replaced. Should I call this normal & just replace the shaft seal? I can do that without pulling the trans. I'm really not looking forward to pulling the trans once again, after only 2-3 hours of run time. 

I'm very curious as to why the shaft seal failed? maybe it did'nt get replaced? 

 
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if the pilot bearing is slopy on the motor behind the clutch, the seals can leak, the 2D has 2 seals in them, the Seq trans has one seal, sometimes they will leak, try to find a seal that leaks the least, might have got debris in it, 

The input shaft moves around due to it not being solid, it is two parts, behind the diff is a slip collar, the collar has spines and the shaft has spines, the collar holds the input shaft to the main shaft, 

If you pull on the input shaft and it came all the way out, then you would have a issues, 

If the shaft was not installed deep enough and the throw out bearing sleeve was pushing against it, then it might leak, 

I would replace the seal, and make sure it is in all the way, look at the back of the throw out bearing collar for the correct depth,  

 
I'll have to dig out my invoice from the re-build... I believe the pilot bearings were just replaced. Should I call this normal & just replace the shaft seal? I can do that without pulling the trans. I'm really not looking forward to pulling the trans once again, after only 2-3 hours of run time. 

I'm very curious as to why the shaft seal failed? maybe it did'nt get replaced? 
The throw out bearing (aka T.O. bearing) would most likely have been replaced during a transaxle rebuild.  The pilot bearing is in the engine crank, not on the transaxle, so it would not have been replaced with a transaxle rebuild.  You will need to pull the clutch off the engine to replace the pilot bearing.  Get a quality pilot bearing removal tool.

The input shaft on the transaxle mates with the pilot bearing on the engine crank.  As @J Alper stated the pilot bearing keeps the two piece input shaft from moving around.  It spins, hence the input shaft seal, but will have very little up/down or side to side movement.  If your pilot bearing is bad this may be allowing those movements and is why you are seeing a diff fluid leak at the seal.  

 
I don't have a PBS, but my Fortin sure doesn't move like that.

The S4's that I have helped install, didn't move like that either.

 
I don't have a PBS, but my Fortin sure doesn't move like that.

The S4's that I have helped install, didn't move like that either.
its is just moving that much in the vid, because the Throw-out slide collar is removed, IMG_7770.JPG

 
In the pic is where the seal rides, it is not a rigid shaft it has a slide collar to mate the input shaft to the drive shaft, if the bellhousing is removed you can move it up and down about 1'' 

 
@J Alper @L.R.S. I think I found the cause! 😀 The pilot bearing was falling apart & maybe got its feelings hurt when I installed the motor? 

So I'll run with the assumption that the pilot bearing failure caused the seal failure? Install the 2 new parts and run it? 

I suspect most of the shaft slop should go away when I get the new seal & T.O. slider is in place.?.

I love this forum, you guys rock! 

20221025_112141.jpg

 
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Up/Down and side to side play in the input shaft while the engine is out is normal. Pilot bearing in crank supports the engine side of the input shaft once installed in the engine.

In/Out movement is bad, which typically means the mainshaft bearing needs to be replaced.

 
What motor do you have, if a LS, then use the Corvette Bearing, 

ACDelco 12557583 ACDelco Pilot Bearings and Bushings | Summit Racing
That is NOT the correct bearing when using a PBS with a chevy bell housing, or any Weddle/Mendeola S4/S4D with PBS chevy bell housing. These will require the smaller needle bearing and adapter sleeve that installs deep in the crank.

https://weddleindustries.com/products/CL-PILOT-28/CL-PILOT-28

The bearing that sits flush with the end of the crank will not allow the engine and trans to come together. The clutch splines on the input shaft will bottom out against the bearing before the mating surfaces come together.

For information purposes, the PBS chevy bell housings will have a PBS logo cast into them, they will also use the external hydraulic slave cylinder, with a block mounted starter. These were used on quite a few Weddle/Mendeola S4/S4D transmissions built from 2010-2020. 

 
Thanks @Sean@Weddle! Great detailed information! 

I would have preferred to run the sealed bearing, but I did determin after measurements it wouldn't work.  A whole lot of work for a failed $25 dollar part. 

Thanks to all for their input & time! 😀

 
Was the pilot bearing new when you put the trans on last time?  

Either way, the above is why you never ever ever ever use the bolts to pull the motor onto the trans: too easy to f*ck things up.  Take the time to get the motor lined up and push it on by hand. :biggrin:

 
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