Drive alignment: Any TRS experts left out there?
 

I broke a gimbal ring on one of my drives and installed a complete new assembled transom assembly- gimbal ring, housing and bell housing. Now I can't get the drive shaft to go into the coupler. I have a bravo alignment tool, but not a TRS with the disc. Here's what has me stumped- I can't even get the alignment tool to slip into the trans. coupler- I can feel the angled chamfer at the end of the shaft sit into the end of the coupler hole but it will not push in beyond that. I thought that a misalignment between the coupler and the rear bearing must be the reson, but now I realize that the rear bearing and the trans coupler are both mounted into the trannie tailstock snout, so the hole alignment can't be adjusted with the engine mounts. If anyone can enlighten me as what's going here it would help prevent a suicide!

The bearing still has to be lined up with the coupler for the shaft to go in. When the gimbal ring broke you may have also cracked tailstock on trans or shifted bearing. The disc on the alignment tool then is used to align engine/trans with bell housing/drive.

Thanks. I've inspected everything pretty closely, especially during the many hrs. I've already messed with trying to mount the drive- I don't think anything else is cracked or broken. Are you saying that moving the engine will change the bearing/ coupler alignment or are you saying that if the tool won't go in the tailstock has to be broken?
When I sight the coupler through the bearing hole it looks like its aligned at least close enough for the shaft to go in-

I wrestled with one a couple weeks ago. I used a cherry picker to hold the drive, the slid it on. It went good until the drive was about an inch away from fully seating. Then I had to wiggle the drive up and down a few times in the motion that the rams would normally move it if you were trimming it up and down. I hope you get what I'm saying, and it finally slid in. While I was moving it up and down I was also turning the prop shaft in case there was some spline mis-alignment too.

Thanks- that's pretty much the same approach I've been trying. In my case though, the shaft will not go into the coupler at all, nor will an alignment tool, even though the rear bearing and the coupler look aligned-

What transmission?

B-W Velvet Drive

Moving the eng will not change the bearing to coupler alignment. If I remember correctly the bearing is pressed into tailstock and should self align. If the bearing is worn it may cause the problem. Try lifting up and wiggling the alignment tool while you push it in. You could also try different alignment tool, not sure if the newer ones can be used on the TRS, check to see if step on tool is hitting bearing and not fitting in. Or take shaft off drive and see if it will go in.

I have one that is really hard to get on. I think that I have a spline that is a little messed up? I was told that TRS drives do not need to be aligned like a Bravo is this true?

Yes TRS has to alined with engine its a little different that Bravo. There is a large washer that goes in the helmit that tool slides into tranny tail stock for alinement.

Here is a trick I have found that is very helpful for putting a TRS on a boat with Warner tranny.

When installing a TRS if you take a long thin screw driver and slip it in between drive and helmit as drive is being put on. Now use the screw driver in were u-joints are to wiggel the input shaft into the tanny spline while turning prop shaft and pushing drive in. Kind of hard to discripe this but you should get the idea. Screw driver is helping keep the front of input shaft from flopping down in the space between the tail sock bearing and the spline in rear of tranny

I really appreciate all the input and suggestions. After taking another hard look at it, my working theory now is that the end tips of the splines in the coupler are slightly buggered up and not letting the shaft splines slide past. When the Gimbal Ring broke and the shaft slipped out, I heard a grating noise as I powered down. I think the drive shaft end was just making contact with the end of the coupler hole and grating on the splines. Its hard to tell looking down the drive boot through the bearing hole with a light, but the ends of the coupler splines look a little flattened. The shaft itself barely looks a little scuffed, but who knows, it may be a harder steel then the coupler. I'm gonna try removing the rear bearing and working between the coupler splines with trianglular rat file and see if that does the trick-

Yes the file will work done it many times Put spline gease on shaft too

Just thought I'd post the end of the story in case it helps anyone else in the future: what finally solved my problem was filing between the splines on the coupler and a little bit on the shaft w/ a triangular file- they got rubbed at the very end when the shaft slipped out of the tranny. We hoisted the drive from above and wiggled it in 'til we could feel contact w/ the splines while turning the prop shaft. Then we had to put a block of wood across the drive directly behind the shaft and whack it "gently" with a 5 lb. mallet. It took 2-3 whacks to move the drive in far enough to get the nuts started. After so many wasted hours trying to solve this problem I'm convinced that all the "tricks" like a screwdriver on the U-joint, string around the shaft, tape around the shaft etc. are completely defeated by the rear bearing which is permanently aligned with the coupler by the tailstock. I think when the parts are new they slid together easily but what most of us are dealing with is wear to the splines on the shaft and coupler.

If you had to "pull" the drive in with the nuts your really going to have some fun the next time it needs to come off.

I hear what you're saying but it took very little effort on the nuts to move the drive in- If we had to, we probably could have pushed the drive in by hand, but its such a clumsy beast to get any force behind. I think the sides of the splines make just enough contact to make it difficult-