Alignment and coupler question 1979 Mercruiser 260

[Kareo]

Member
I have a 1979 Mercruiser 260. The engine was replaced about 10 years ago (less than 50 hours on it now) .

I pulled the outdrive to replace the shift cable, found water in the bellows and replaced the u joints, bellows and gimble bearing. Only took me like 3 days of work.

When I pulled the drive, it was very difficult to get out (I had to reattach the trim rods and use them to push it off. When I checked the alignment after installing the new gimble I found out why. The alignment tool doesn't even go into the coupler, it hits on the top by a couple of millimeters.

I went to adjust the front mounts, and they look like they are already almost all the way down. I'll attach a picture, but I can maybe get a couple more turns, 2 millimeters tops before they bottom out (it's so close I can't get a wrench on them, would need a service wrench I think to fit in the gap). I can't imagine it will be enough to fix the issue though.

Am I missing something? I almost feel like the rear mounts are too low? What's the smart way to resolve this?

Also, when I look at the coupler, it doesn't look right to me. It looks like part of it is pushed in more than the rest. I'll attach a photo.

When I had the boat out last weekend it ran fine, no noticeable issues other then stalling during shifts, which is how I went down this rabbit hole starting with the shift cable.

I don't have any way to hoist the engine, so I'll probably have to take it to a mechanic this week, which is frustrating after fixing all the other problems. I was hoping to slide it back on and be on the water today, and here I am...

What are the thoughts of the hive mind? Is there something I'm not thinking of to get this drive back on properly

 

[flashback]

Are there any splines in the coupler? Hard to tell from the picture. Be sure the new gimbal bearing is aligned..

 

[alldodge]

I went to adjust the front mounts, and they look like they are already almost all the way down. I'll attach a picture, but I can maybe get a couple more turns, 2 millimeters tops before they bottom out (it's so close I can't get a wrench on them, would need a service wrench I think to fit in the gap). I can't imagine it will be enough to fix the issue though.

If correct the rear mounts probably need to be replaced

 

[Kareo]

Are there any splines in the coupler? Hard to tell from the picture. Be sure the new gimbal bearing is aligned..

Yes, there are splines in the coupler. It was working fine last weekend, the only reason I pulled it apart was water in the bellows. There didn't seem to be much if any grease on that shaft, and it was extremely difficult to pull it out.

 

[Kareo]

If correct the rear mounts probably need to be replaced

That's what I kind of thought. I assume you need some way to hoist the engine to do that though

 

[kenny nunez]

With a small bottle jack under the front of the engine to raise it, remove the top nut then the lag screws holding the mounts after the mounts are out remove the bottom nuts and reinstall the mounts. Raise and lower the engine with the jack until the alignment is right. If there is space under where the nuts are removed cut a slot in some flat washers as a shim to make up the clearance.