Mike77

While refinishing my TRS drives and replacing the bellows I noticed the port drive tailstock bearing does not spin freely by hand (BW trans). So I ordered a replacement. I test fit the new bearing on the yoke, without the o-rings and the new bearing is sloppy/wobbly on the yoke. I slid the new bearing on the starboard yoke and it is a much tighter fit.

How much slop, if any, is acceptable on these units?
When the drive is slid back in and mounted, how far does this splined shaft extend into the tailstock bearing? There are two o-rings on the shaft; do these o-rings end up in the tailstock bearing?
If it needs to be replaced does anyone have a good used one for sale (57749A 1 YOKE ASSY)?

Thanks,
Mike

airjunky

Are you talking about the "gimbal" bearing that is held in the end of tailstock with a snap ring? Or the output yoke support bearing? Both of those should be no slop tight .this would be a good time to take a real close look at the yoke u joints while its out you dont want to see what happens when one of those fail on that unit

airjunky

I have a ready to run tailstock if that one ends up being un useable

Mike77

Yes the "gimbal" bearing, although on this unit it's a straight bearing, no spherical component; the one held in with the snap ring. Although the yoke does not look scored, I am guessing this bearing has been locked up for a while and the yoke is worn from that contact? The bearing fit is definitely too sloppy for my taste; not a machined flat finish like the starboard yoke.

When the drive is reinstalled, how far does that splined yoke go into that aft bearing? There are 2 o-rings there and I'm wondering where they end up in relation to the bearing, forward, aft or straddling both o-rings? I'm just curious as I know this is not a fit that we shim for.

The u-joints do NOT look original, appear to be in good shape with no detectable slop. To change the yoke I'll have to at least remove the forward u-joint and will check for wear once it's out and caps off. Will these caps press out with a large c-clamp (c-clips removed of course)? Previous experience with these c-clip ujoints was on car driveshafts and I could always use the bench vise to press them out. What is normally used for these?

What is the condition of the splined yoke you have for sale and how much do you want for it? PM a pic or two if you get a chance.

Thanks,
Mike

airjunky

Have no idea what kind of boat your working on but in a pinch on those for that kind of job ive fabbed up some quick 4x4 cross braces (2 at top) the large hd ratchet straps unload motor enough to boost it out of the transom plate hole where the rubber ring goes in your going to make a mess if you havent drained the velvet drive and pull it on out of there .dont believe there is any choice where the shaft sets to the tailstock unless you are missing parts or something kind of like sticking a t5 in a stang .yea sounds like that bearing spun out and cooked the tailstock suprised it wasnt squealing like a pig .prob want to make sure it isnt getting loaded wrong by rear mount ear bushings or a squished transom or something odd like that

picklenjim

There is no such thing as a "gimble bearing" on a TRS. That is the trans tailstock bearing. With a long set of snap ring pliers the bearing can be changed from outside the boat. No need to pull the engine/trans. Make sure the bearing hasn't spun in the trans tailstock after you get the snap ring off. As for removing the yoke shaft from the U-joint you can borrow a u-joint press from Auto Zone or Orielly's free. Deposit required but returned. Much easier than jacking around with a C-clamp. C-clamp won't do it anyway. As for where the bearing rides it is at least straddling both O-rings. No way it would be out anymore towards the splined end. It's possible the o-rings make up for the slop you are seeing, especially if the yoke shaft has no scaring or marking of any kind. If you want to know exactly where the bearing rides you can measure from the bearing to the drive mating surface on the bell housing. Then measure that distance from the mating surface on the drive out to the yoke shaft. I have a shaft and bearing out at my shop I will check how the fit is on it and get back to you.

picklenjim

Looked at one of these I have today. I was able to see right where the bearing was in relation to the O-rings. It is almost exactly centered on top of the o-ring closest to the splined end. Other o-ring is about 1/8th" from the bearing.

Mike77

I wonder what the purpose of that extra o-ring is?

Thanks for the update,
Mike

airjunky

Thats why i put gimbal bearing in parentesis .its in the transom plate but not part of it , and it could be a beating to replace the tailstock without some moving of the engine if he doesnt have some kind of driveshaft extension all i heard was trs .if it locked and spun in the bearing opening and now flops , might be time for plan b

airjunky

As long as you have a oring sealing the splines and keeping water out of that cavity between inner and outer bearings its all good .if the stepped part of the yoke butts up to the inner race of the outer yoke bearing , you may of found out why it failed