OMC 800 Shift failure

Greetings
I own a 1982 Viking Cuddy with a V6/omc 800 powertrain.

Last time it ran i was pulling a kneeboarder and was turning to retitieve after they dumped. I slowed before turning and tried to turn wide.At that point i had a major malfuntion. Some how my motor mount and drive mounts both tore ouf of the deck causing about a 10 degree rotation and a 3.5 inch lift on one side.

Used my handy OMC attitude adjuster to get the engine back in place but no longer have any engagement into forward or reverse.Checked the plate on engine (not sure what its called) to confirm it was moving,it was. I have no noise or prop rotation and i think the ball gear is turning.(it grinds when i raise the drive. I know the ball gears need replacement but does anyone know how i should proceed to troubleshoot the "shift"issue? And also any advice on how to remount the motor/drive mounts?

Re: OMC 800 Shift failure

So the motor runs?

Does it over heat?

What i think happened is the coupler went.

When the motor mount gave out and it tipped on the side the motor, it put a tremendous stress on the coupler and the drive.

Ok first with motor off drive fully down on the trailer, advance the throttle to engage the gear.

Can you turn the prop? If prop turns than look under drive when turning the prop does the ball gears move?

If the ball gears move than it's the coupler .

If the ball gears don't' move and you can turn the prop it's the water pump shafts in the drive.

Post back your results and we will go from there.

Re: OMC 800 Shift failure

Motor runs...no heating issues...


Prop spins....Ball gear does not...seems its the shaft...



Next question...is there a conversion kit available to swap drive to a Mercruiser?...


I fear when i drop this OMC i will find it needs quite a bit of work...and with parts like they are mayhaps i should consider a swap?...


Opinions would be greatly appreciated

Re: OMC 800 Shift failure

If it is the shaft, and the gears are good maybe 79 bucks for one shaft, 80 to 100 for the other shaft, and maybe 50 for a impeller kit with housing.

I threw in the impeller kit cause would be a good time to replace when apart already.

Now to the issue of the motor mounts, engine gotta come out.

No replacement of the out drive im afraid to a merc. Unless you want to spend twice what the boat is worth.

I thought about your problem and i still think the coupler would go also, when engine out you can check it. And the shaft that connects to the coupler.

All bad news but stringers rotten maybe? Why would the motor jump and lay on it's side.

Transom also maybe rotten.

I feel your pain post when you get it all apart and the motor out maybe we can help.

Re: OMC 800 Shift failure

With no water going to the motor how did it not overheat?

Re: OMC 800 Shift failure

Shut down motor at first sign of failure...only run momentarily since..Sorry i asked about the drive swap...have since read the countless posts regarding that.

I think a complete tear down of the power train may be in order....Think i have the motor mount issue worked out... They had the mounts screwed to the deck with lag bolts...they just stripped out of the holes. My plan ist to mount steel plates fore and aft of the mount plate and weld the mount to those. Not quite factory but should suffice.

Im afriad if the damage is too severe i will have to dump the hull and part out the rest as parts seem a little steep.....but the again it is an Antique. Seems a shame tho....dont see too many boats like this on the water anymore.

Thanks a million for you help...im sure you will see me post again as the process unfolds. I`ll keep you up to date