Seized 2.5hp Johnson.

[steviecops]

Hi<br />I've got the chance to get a 1987 Johnson 2.5 that is seized. Obviously, it is very cheap but I wondered if it would be a worthwhile project given the history of the engine.<br /><br />Apparently, it was bought as an auxillary engine, and never used! But somehow, it's ended up seized. Sounds strange to me how an engine can just seize up for no reason, but maybe someone on here knows something that could cause it.<br /><br />I've looked at the engine, and it does look brand new. However, there is absolutely no movement on the flywheel or prop. I did get a seized Yamaha 2hp recently that had a water pump housing full of salt corrosion and it had grabbed the drive shaft and gave the impression of a seized engine. Once I cut the housing off and replaced it, the engine was fine.<br /><br />That still doesn't explain how a "never used" engine can seize up though. I'm thinking that maybe the engine was submerged at some point, but there is no sign of corrosion anywhere on the engine.<br /><br />Any advice would be appreciated.<br />Thanks<br />Steve

 

[wayne h]

Re: Seized 2.5hp Johnson.

it can happen if its cheap it might be a nice little project that might not need alot of work i bought a 9.9 that was seized just from lack of use and getting sprayed off the back of the boat i pulled the plugs and used 2 cans of PB blaster with the plug holes up i kept spraying the cylinders every few days and just letting her soak after like a week of soaking i then tryed to move the fly wheel BY HAND she moved 1/4 turn so i just kept spraying her up and letting her soak. i did not force it to turn over i just moved it back and forth a few times a week and she moved more and more every time i tryed this took me about 2-3 weeks but it worked and has been on my dad boat for 6 years now touble free. i am not saying that u will have luck like that but its its cheap it worth a chance if its not worth fixing then its gonna have parts on it that u can sell on ebay and probobly make more off that then what u payed for it

 

[Solittle]

Re: Seized 2.5hp Johnson.

Take the plugs out and put it on the floor with the plug holes up. Pour a couple of tablespoons of Marvel Mystery Oil into each cylinder and let it sit for a few days. Then follow wayne's suggestions. Marvel Mystery Oil seems to work wonders.

 

[steviecops]

Re: Seized 2.5hp Johnson.

Thanks for the advice. I think I'll give it a go then. I'll let you know how it works out.<br /><br />Steve

 

[Chinewalker]

Re: Seized 2.5hp Johnson.

Hi Steve,<br /> Also, another reason why those motors are likely to seize - the dreaded 100:1 oil mixture they originally ran! It simply didn't leave enough of a film to properly protect parts for extended periods of non-use. I would STRONGLY recommend a teardown, even a partial one, to inspect the rod and crankshaft bearings. Often, a seizure is related to these bearings developing a coat of rust. Even if you were to Mystery Oil it loose without a teardown, it wouldn't be long for this world with rusted bearings. You'd also be able to see if the rings are stuck in their grooves - another common issue with stuck motors. A manual is strongly recommended!<br />- Scott