OMC Engine Alignment...

[holgo123]

I am in the process if putting a boat back together after rplacing the transom. I have also replaced the gimbal bearing. It is a 1993 Chris Craft BR217 w/OMC Cobra 5.0 l EFI. I am aligning the engine. I had a hard time getting then engine back in the mounting holes on the front bracket, but did and got everything all bolted up. I had to lower the engine to get the alignment tool in. I am trying to get it to go in easier, but lowering it more did not help much. It is still a tighter fit on the bottom of the alignment tool (I put grease on the tool and look at the grooves left after pulling it out). I have searched the board for tips, but couldn't find much. I did find this post left by Don S. and was wondering if this applied to any new install of a gimbal bearing. Don S. wrote:

It internal ring if the gimbal bearing can be moved compared to the outside.
After installing the gimbal bearing, put the alignment bar into the coupler as far as you can, then bump it with a rubber mallet up and down, side to side and push the bar in some more. This will get the internal part of the bearing aligned with the coupler. May have to do that a couple of times to get the bearing aligned unless the engine was out of alignment before the change.
__________________

Don S.
Alive and Well in Ocean Shores WA.



Why is there never enough time to do it right the first time,
But always enough time to do it again?

If not, any other thoughts? The alignment tool does go in, but I think it is too tight... Thank you!

 

[Don S]

Re: OMC Engine Alignment...

That process only aligns the inside of the gimble bearing to the coupler a little bit. Now, you have to align the engine to the alignment bar to make the alignment bar go in and out of the coupler very easily. This requiers you raise or lower the front motor mounts to find the best alignment. You may have to do the tapping of the bar up and down, side to side quite a few times while adjusting the motor mounts. Also try to keep equal weight on each front mount and recheck the alignment after tightening the lock nuts.
Then turn the engine 90, 180, 270? to make sure every thing stays the same.

 

[blueoval1]

Re: OMC Engine Alignment...

The post from Don that you refer to worked perfect on my 4.3 Cobra.
I had run the motor without the drive after installing new gimble bearing , and had a hard time with realigning.
Follow Dons' advice , it worked pefect for me!

 

[holgo123]

Re: OMC Engine Alignment...

I hope this doesn't sound stupid, but is there a point that raising the front mounts lowers the coupler hole and vice versa? It seems like the mounts can pivot the coupler hole up if lowered all the way... I have lowered mine all the way and it is still tight on the bottom of the alignment tool. I am going to go play with it a little more...

 

[Don S]

Re: OMC Engine Alignment...

On the Cobra's, the rear mounts of the flywheel cover MUST go down over the square parts of the rear mount bolts, then the big thick washer must fit into the recess perfectly. If the square part isn't sitting in the bottom, then it will raise the back of the engine up and cause your problem.

 

[holgo123]

Re: OMC Engine Alignment...

Don, thank you for the input. I took a mirror and verified that the rear mounts are flush with the flywheel cover and the square nuts are in the slots. I raised the motor a little because I had the front mounts bottomed out. I put the tool in and tapped it on all four sides. It centered itself and the tool slides in & out easily. Thank you. I can't remember seeing that in any of the manuals... I am going to torque it all down and rotate the engine to verify that all is good. I was worried to death that I had changed something in the geometry when rebuilding the transom... Hopefully this will be close to the last hurdle. I still have to to crank an engine that has sat for a year after a water intrusion event (I did get it running and changed the fluids before parking it...)