1986 Four Winns 170 MCM Engine siezed

[jfondario]

I own a 86 4winns 170 Horizon with a Mercruiser inline 4 170 MCM engine in it. It has been sitting in a garage for 5 years now and I went to pull it out to see if I can get it running again but when I went to manually turn the engine over just to see if it would I got no movement what so ever. I went ahead and pulled the plugs and let it soak in Marvel Mystery oil for 3 days now and i still can't get it to bump "start". I placed some more oil in there hoping that more time will help with it loosen up. I placed a socket/rachet on the bolt where the crank pulley is and tried to move it but after tightening the bolt I thought I would stop since if I snap that bolt off I am really screwed. Just wondering if anyone has anymore suggestions on how to get it loose minus ripping the entire engine out and cleaning/rebuilding it? Thanks ahead of time for any help!! I kick myself everyday now for letting it sit for so long without running it. I know I know amateur move.

 

[rickryder]

Re: 1986 Four Winns 170 MCM Engine siezed

That's a tough one..... I have had luck with Seafoam Deep Creep penetrating oil.....you could also try pulling the starter and try to get a pry bar on the teeth on the flywheel.....other option is pull the head and see how much rust is in the cylinders.... Tap the piston tops with a block of wood....Guess you didn't fog the engine when you laid it up for 5 years....

 

[jfondario]

Re: 1986 Four Winns 170 MCM Engine siezed

That's a tough one..... I have had luck with Seafoam Deep Creep penetrating oil.....you could also try pulling the starter and try to get a pry bar on the teeth on the flywheel.....other option is pull the head and see how much rust is in the cylinders.... Tap the piston tops with a block of wood....Guess you didn't fog the engine when you laid it up for 5 years....

Huh, Ill have to check out that Seafoam you speak of. Never though of trying to get at the flywheel behinid the starter. Good stuff man!! Nice boat too . Thanks for the tips. Ill let ya know how it goes.

 

[DBreskin]

Re: 1986 Four Winns 170 MCM Engine siezed

Welcome and good luck. Your question is not Four Winns specific, it's really a Mercruiser or general engine question. I suggest you post in one of those forums.