Rebuild Black max 200 myself?

[willp2]

Hello,
A friend of mine has a mid 1980's Blackmax 200 that needs rod bearings replaced. I'm considering buying it for a project boat I am working on. I can get the thing for next to nothing. Is rebuilding this something that is doable by a knucklehead like me with reasonable mechanical skills or should I just run away from this?

I’m not scared of a rebuild if I can get parts and instructions, but clearly this would be a big job. How big a project is this and what are the big gotchas I might run into.

Thanks!

 

[andy6374]

Re: Rebuild Black max 200 myself?

Well, the cylinders on the 200 and 225's had chrome sleeves and can't be rebored. So if they are damaged you need a new block. But if they are okay, then I think you would be able to do the job yourself. The most important thing is to figure out what caused the rod bearings to go in the first place (lack of oil???) and correct the problem.

First and foremost you are going to need a mercury factory manual. While you've got it disassembled you might to replace the upper and lower crank bearings and some other stuff. Maybe Laddies or somebody else who has rebuilt these engines could chime in here.

 

[willp2]

Re: Rebuild Black max 200 myself?

Thanks, that's the kind of info I was hoping for. Is there anyway to get an idea on the condition of the cylinders? I'm guessing probably not without opening the thing up.

I am of course concerened about why the bearing went bad in the first place. I'd hate to get through all this only to find out there is an oil flow problem and the engine goes to hell again.

If I'm going to do this (and I'm not sure I will at this point) I would want to replace or renew anything I can reach while I'm in there.

Thanks!

 

[andy6374]

Re: Rebuild Black max 200 myself?

Just run a premix and forget about the oil injection.

The manual says to swab muratic acid on the sleeves. The acid will not affect the chrome but will bubble when in contact with aluminum. So there is any pitting or holes in the sleeves you'll know. Clean that stuff out thoroughly when done.

Also take measurements of the bore to make sure they are within specs.

This is all in the manual

 

[alousteau]

Re: Rebuild Black max 200 myself?

just finished rebuilding a 175, I know not a 200, but it is fairly simple. Get a good manual! Not near as complicated as a 4 stroke. Get a good torque wrench, lbs and in and a good manual. I have both the clymers and the seloc. The clymers is much better and detailed. A factory one would be best though.

 

[willp2]

Re: Rebuild Black max 200 myself?

Thats what I want to hear. How much did the rebuid cost doing it yourself? Any problems finding parts?

Thanks!