Siezed powerhead any ideas 2003 Johnson 25

[maineiac5586]

I have a 2003 Johnson 25 hp 2 stroke with a stuck powerhead. I lowered the lower unit to make sure the problem wasn't in the lower unit. I have tried the product Engine Release two times following the directions exactly (the product actually worked on a NIssan 8 hp I had with siezed pistons. I put an impact gun on the crank pulley nut (as per the instructions included with the Engine Release product), the engine didn't budge. I actually wound up stripping the crank pulley nut in the process (crank threads still good). I don't know what happened to cause the siezure as I bought the motor this way. The previous owner said it was not related to a lack of oil but who knows. He said he stored it at the end of season last year and this is how he found it this year. This is a clean outboard with electric start and really worth fixing. I have been looking for a used powerhead to replace it but have not confirmed what year powerheads interchange. Does anyone have any idea where to go from here? I really want to keep this outboard and not resort to parting it out. When I first removed the head I found rust in the cylinders (it looks a little better now after having been soaked with the engine release product. I will welcome all ideas on where to go from here. thanks

 

[Bosunsmate]

Re: Siezed powerhead any ideas 2003 Johnson 25

Both your bores look scratched, should hone out ok but i think you should look at splitting the crankcase and having a look as whatever caused those scratches could do it again.
You could take off the exhaust plate and have a look in there and spray some lubricant/penetrant in there

 

[rrw]

Re: Siezed powerhead any ideas 2003 Johnson 25

Wow, cool motor. As far as getting it loose, I would try to get some leverage on the outside of the flywheel, you have so much more energy out there than on the nut in the middle. I would repeatedly spray it and let it soak with a good penetratingt lube, I prefer Kroil. once its loose then the fun begins.

 

[maineiac5586]

Re: Siezed powerhead any ideas 2003 Johnson 25

Any idea how to turn the flywheel on the outside diameter to try to unstick this motor?

 

[maineiac5586]

Re: Siezed powerhead any ideas 2003 Johnson 25

also can I remove the powerhead leaving the lower unit bolted up. The driveshaft is not stuck in the bottom of the crank as I unbolted and rebolted the lower unit recently to make sure the lower unit wasn't siezed.

 

[AlTn]

Re: Siezed powerhead any ideas 2003 Johnson 25

yes, the powerhead is mounted to the exhaust housing and will lift off with the lower unit in place

 

[rrw]

Re: Siezed powerhead any ideas 2003 Johnson 25

Any idea how to turn the flywheel on the outside diameter to try to unstick this motor?

Usually there should be something really solid you can pry against, then stick the end of your bar in-between 2 teeth on the flywheel. Or if you have a heavy duty strap wrench wrap the strap around the flywheel.

 

[maineiac5586]

Re: Siezed powerhead any ideas 2003 Johnson 25

Any worry about breaking the teeth off? Where are you talking about something solid to pry against? Something on the motor?

 

[rrw]

Re: Siezed powerhead any ideas 2003 Johnson 25

ive never broke any teeth, but i guess you gotta be somewhat carefull. yea something on the motor, does it have those eyelets that youd use to mount a chain to for removalk?

 

[maineiac5586]

Re: Siezed powerhead any ideas 2003 Johnson 25

No. I dont

 

[Lightning1]

Re: Siezed powerhead any ideas 2003 Johnson 25

Block of wood on top of piston.
Tap easy with big hammer.

 

[maineiac5586]

Re: Siezed powerhead any ideas 2003 Johnson 25

yeah, tried that one, no dice