Engine Alignment tool goes in about 1/4 of the way, question.

[1985 Century Mustang]

Hey Everyone - Well I finally put my Merc IO 140 HP Alpha One Gen One Engine in yesterday because of a previous loose coupler issue and it went rather well,, except when I went to align it with that alignment tool, the alignment bar seemed to go in fine and the bar turned easily with 2 fingers as required, but it wouldn't go all the way into the the coupler. I think It went in maybe about 1/4 of the way or less, if that.

In what I am reading it could be that the gimbal bearing needs to be tapped in better, which I never touched,,,, or an alignment issue.

Further, I remember when I tried taking the outdrive off a few weeks ago, it was a real pain in the ass and took some struggling to get the outdrive off.

Question: Could the gimbal bearing have popped out of its original position when I removed the sterndrive? I'm thinking it's either the gimbal bearing or it's not aligned properly. Your thoughts.

 

[1985 Century Mustang]

This video had me thinking, when I was doing a search online with my current issue.

 

[1985 Century Mustang]

Anyhow, I would appreciate any help, newbie here...

 

[dubs283]

How far did the witness marks show the alignment bar entered the coupler?

Yes, the gimbal bearing could be out of alignment. The motor could also need alignment

If the coupler is worn, i.e. slpines are knifed then even a properly aligned gimbal bearing/engine will have a difficult time seating the bar

 

[1985 Century Mustang]

How far did the witness marks show the alignment bar entered the coupler?

Yes, the gimbal bearing could be out of alignment. The motor could also need alignment

If the coupler is worn, i.e. slpines are knifed then even a properly aligned gimbal bearing/engine will have a difficult time seating the bar

The first stage or node of the bar where it enters, went in about an inch, with respect to the witness mark, if that makes sense.

The coupler was inspected, and is not worn,, but again the leg was hard to get off originally... So that had me thinking that something was up prior....

 

[dubs283]

If the drive is hard to remove either the engine is out of alignment or the coupler hasn't been greased for a long time

Either way that means most likely a worn coupler

Got any pictures of the driveshaft splines and coupler?

 

[1985 Century Mustang]

 

[1985 Century Mustang]

 

[1985 Century Mustang]

@dubs283 , no I don't have any pics of the coupler. For what it's worth, the boat was sitting in a driveway covered, for about 12 years unused. Maybe that's why the leg was hard to get off?

 

[dubs283]

Splines are full of old, dried grease and aluminum from the coupler

Guessing it's been a long time since the drive was pulled for routine maintenance and most likely the coupler is severely worn

If you can, post a picture of the coupler. Splines should be squared off on the tops/ridges. If they appear sharp/pointy then the coupler is close to failing

 

[1985 Century Mustang]

Splines are full of old, dried grease and aluminum from the coupler

Guessing it's been a long time since the drive was pulled for routine maintenance and most likely the coupler is severely worn

If you can, post a picture of the coupler. Splines should be squared off on the tops/ridges. If they appear sharp/pointy then the coupler is close to failing

Unfortunately I really don't want to remove the engine again to inspect the coupler, unless there's another way...Maybe a borescope perhaps? The outdrive and coupler worked flawlessly, except for the issue I had with the coupler being loose making that knocking sound.

Here was my original issue.Thats fixed now.

 

[dubs283]

coupler being loose making that knocking sound.

There it is

A loose coupler no question has wear. Sitting 12 years won't cause a coupler to loosen on its own

Probably run for how long with the issue? Can't say for sure but will say you should have at least replaced the coupler when the engine was out

Cheap easy route is to clean as much of the old grease and coupler bits from the drive shaft splines and coupler itself, grease the coupler, install the drive and go boating

Best practice is to replace the coupler, ymmv

 

[1985 Century Mustang]

There it is

A loose coupler no question has wear. Sitting 12 years won't cause a coupler to loosen on its own

Probably run for how long with the issue? Can't say for sure but will say you should have at least replaced the coupler when the engine was out

Cheap easy route is to clean as much of the old grease and coupler bits from the drive shaft splines and coupler itself, grease the coupler, install the drive and go boating

Best practice is to replace the coupler, ymmv

If this matters or makes a difference,,,, I went out in the water several times after I rescued the boat from the driveway without doing any work on it, except for rebuilding the carburetor. The coupler bolts got loose later on, not right away. And there weren't any issues or warnings.

This engine was rebuilt about 12 years ago also, but the boat wasn't really being used, due to a divorce thing, so I'm thinking when they did the rebuild, they may have not tightened the coupler bolts enough or used loctite.

When we took the engine out, a few coupler bolts were loose. But who knows,, thanks for the input.

 

[Bondo]

@dubs283 , no I don't have any pics of the coupler. For what it's worth, the boat was sitting in a driveway covered, for about 12 years unused. Maybe that's why the leg was hard to get off?

Ayuh,..... You should be able to see the splines in through the gimbel bearing,.....

 

[1985 Century Mustang]

Ayuh,..... You should be able to see the splines in through the gimbel bearing,.....

The Splines actually looked good, when I put the coupler back on. I guess I should of taken a few pics I suppose. Again, I'm new at this.

 

[Grub54891]

The bolt holes on the coupler may have gotten hammered also, along with the original bolts. which would make it not set in place properly.

 

[1985 Century Mustang]

The bolt holes on the coupler may have gotten hammered also, along with the original bolts. which would make it not set in place properly.

We Inspected the studs going from the cam to the flywheel, and then onto to the coupler,, they looked fine. The coupler was put back on with loctite this time as I can only assume it wasn't, prior to when it was rebuilt. If I can reset the gimbal bearing or align it, I'll run it with the leg on tomorrow, obviously I will grease it thoroughly, and I'll see what ensues thereafter. Thanks for the input. If worse comes to worse, I'll have to remove the engine and replace the coupler. FWIW, the coupler was hard to find for this engine. Part # on coupler is 59826C, There are some out there, but there pricey too. I guess I'll have to dump another $300 into it for a new coupler, if so. Ughhhhh.

 

[nola mike]

We Inspected the studs going from the cam to the flywheel, and then onto to the coupler,, they looked fine. The coupler was put back on with loctite this time as I can only assume it wasn't, prior to when it was rebuilt. If I can reset the gimbal bearing or align it, I'll run it with the leg on tomorrow, obviously I will grease it thoroughly, and I'll see what ensues thereafter. Thanks for the input. If worse comes to worse, I'll have to remove the engine and replace the coupler. FWIW, the coupler was hard to find for this engine. Part # on coupler is 59826C, There are some out there, but there pricey too. I guess I'll have to dump another $300 into it for a new coupler, if so. Ughhhhh.

Another thing could be collapsed or incorrectly installed rear motor mounts

 

[1985 Century Mustang]

Another thing could be collapsed or incorrectly installed rear motor mounts

The Rear motor mounts are all new, with new bushings, felt washers, etc. It mounted up rather nicely.

 

[1985 Century Mustang]

Does anyone know how to check if the gimbal bearing is in the correct place? Is there a length or some type of measurement etc from the bearing to the outside of the bell housing?