Can't remove front planetary gearset

[teamssc]

Having trouble with the planetary gearset removal on a TH350 (1970's). We can't remove it from the output shaft. On another transmission disassembly it came off easy once the small snap ring was removed. On this current rebuild the small snap ring is removed but we can't get the planetary gearset off. I'm guessing something we can't see is chewed up a little on the gear teeth but for the life of us we can't see it. Is there a trick?

For a reference to the part, if you are not familiar with it, you can see a picture halfway down page 1 of HotRodPC's TH350 info thread. It's the 2nd picture of the two where he discusses the different planetary gearsets. (Thanks HotRodPC)

http://www.gmsquarebody.com/forum/showthread.php?t=911&page=2


Thanks for any suggestions.

 

[HotRodPC]

Welcome to GMSB Don.

So you've got the Sun Gear that goes over the 4 pinion planet right? And to clarify, we're talking about the first set of planetaries inside the Sun Shell right? And you gotten the bitch of a snap ring off the output shaft... And the pinion planet isn't coming off the shaft? The only thing I can think of that would cause that, is the splines on the front of the output shaft are a bit buggered up. I wouldn't imagine the Sun Gear that the pinions are riding on would hold it from coming off. Worse case scenario, maybe you can get a small 3 legged puller to get it off over those splines. Careful not to let the puller damage the output shaft where the center bolt of the puller will be riding on the center of the shaft. Maybe put a heavy flat washer over the hole in the shaft.

I think I recall having this issue once and it was indeed a buggered up output shaft and I did bump a couple splines with a grinder bit off of a Dremel tool to get the burrs off. On the end of that shaft right there, the splines aren't critical so long as there is enough there to hold the snap ring in place.

 

[HotRodPC]

If I understand right, you're talking about this planet? As you can tell, the pinions ride on the sun gear. The planet carrier itself is splined to the output shaft held on by the snap ring. So as long as the snap ring is off, there is only 2 things that can be holding it. Buggered splines on the output shaft or the meshing of the pinions on the sun gear.

 

[teamssc]

Yes HotRodPC, that's the part. We do have the snap ring off so it's got to be something with the spindles. It's like there is a second snap ring, though I know there is not, so it's got to be some slight damage on the spindles based on what you are saying. I'll see if my buddy has a gear puller of some kind. I know I have a dremel but I can't see any damage so not much I can debur while it's still together.

 

[crazy4offroad]

If the bushing in the output shaft was mangled or gone, the pilot end of the input shaft that slides in it could have wallered around and expanded it, and will make it hard to get off there. Pics??

 

[teamssc]

In the end it was pretty painless to get off. We went to Autozone and borrowed a gear puller. Using that with a dime on the shaft the gear came off almost like it was hardly stuck. In fact we didn't even use a wrench on the gear puller and just turned the bolt with our fingers. Once off we didn't see any obvious damage but we'll sit down with a magnifying glass and drimel and clean anything up. I did take pics but nothing looked out of the ordinary nor showed obvious damage show they're not worth posting.

Thanks all

 

[HotRodPC]

In the end it was pretty painless to get off. We went to Autozone and borrowed a gear puller. Using that with a dime on the shaft the gear came off almost like it was hardly stuck. In fact we didn't even use a wrench on the gear puller and just turned the bolt with our fingers. Once off we didn't see any obvious damage but we'll sit down with a magnifying glass and drimel and clean anything up. I did take pics but nothing looked out of the ordinary nor showed obvious damage show they're not worth posting.

Thanks all

It could have been just tiniest of burrs and it cleaned itself off as you pulled it off. Could have even been a sliver of debris having 1 spline wedged. It happens. I've had a couple like that and used them on the rebuild since all appeared to be just fine.

Glad you got it apart. Thanks for the update.