Maybe Siezed Motor Hopefully Not

[igofishn]

I have used you guys in the past and have always appreciated your help.
I have twin 1991 Yamaha 150 that I am unwinterizing Everything OK with Port Motor. Starboard motor would not turn over. Batteries are fine. I pulled the plugs and can barely turn the fly wheel. The plugs looked fine with a slight buildup of carbon. I removed all 8 bolts to remove the lower unit and it slightly dropped but will not come off. I tried tapping on the unit but would not budge any further. I am thinking that maybe the drive shaft is stuck to the drive shaft bushing or is this something else. Any helpfully advise on trying to get the lower unit off. Do"s and Don'ts
Or do I have a siezed motor or bearing? Or what else ot look for.

I would appreciate any input.
Thanks

 

[rodbolt]

Re: Maybe Siezed Motor Hopefully Not

if the motors are 25" shaft models it has a bushing that can swell and grab the shaft, its now a matter of working the unit off. I have been known to cut Oak wedges and drive them apart.

 

[igofishn]

Re: Maybe Siezed Motor Hopefully Not

Thanks for your info and Yes they are 25" Shafts.

Thats what I thought. Do Thoughs Bushing need replacements or can they be stone open. What should the ID be.

Can I put downward pressure on the lower unit, with the shims and turn the flywheel or is this going to cause some damage to the pistons or cylinder walls.

 

[rodbolt]

Re: Maybe Siezed Motor Hopefully Not

if its stuck in the bushing your ok, if the splines are rusted in the crankshaft you may tear up the lower main bearing. yearly maint would have caught and prevented stuck gearcases

 

[igofishn]

Re: Maybe Siezed Motor Hopefully Not

I had the lower unit of last season. I cleaned and greased the splines and also greased up the bushing so I don't think that the splines are rusted. When I get the Lower Unit off should I change that bushing or can I hone it open to the spec size. Do you know the ID of that Bushing and what type of material it is made from.