Seized Mercury 50hp

[briaineo]

Hi

I've picked up a non running seized Mercury 50hp outboard for next to nothing.

Was wondering what the first step I should take is?

I'd imagine it should remove the spark plugs (place engine spark plug end facing upwards) and pour a freeing solution down in the cylinders.

Is this correct, can you recommend a solution to put in. Across the pond so is there any generic type of solution to use?

 

[bilge rat jim]

Re: Seized Mercury 50hp

First, remove the gearcase to determine if the powerhead is seized, or the gearcase.

 

[briaineo]

Re: Seized Mercury 50hp

I'll remove the gear case first.

Can anyone recommend a solution to pour into the cylinders?

 

[racerone]

Re: Seized Mercury 50hp

Remove the bypass covers on the intake side of the motor and have a look in there.----If there is lots of corrosion and rust then the entire motor must come apart for inspection.

 

[bgc]

Re: Seized Mercury 50hp

KROIL has worked great for us getting parts un-stuck.

 

[Chinewalker]

Re: Seized Mercury 50hp

If it is not the lower unit, I would tear the powerhead apart to see what the issue is. Too many steel bearings inside that can cause issues down the road should you manage to free it up with any of the various penetrating oils and elixirs.