Looking at 2001 - 90 hp Mrcury

[JCFERG]

I am considering purchasing a 16' boat with a 2001 - 90 hp mercury outboard. The owner states that the compression is 129, 129, 35. He also states that the boat starts right up, idles fine but runs ruff when given throttle.

My question, does this sound like serious damage (ie. cracked block), I am expecting to replace a ring or piston, but don't want more serious damage. Will an outboard run with a cracked block? Any tests or what to look for?

Thanks

 

[Dunaruna]

Re: Looking at 2001 - 90 hp Mrcury

The hardest thing about buying a boat is knowing when to walk away, we tend to get dazzled by nicely shaped hulls and shiny fittings. You have been handed a very clear clue as to why you should walk away OR receive a generous discount on the value price. In this financial climate, it is a buyers market.

The problem could be anything from a faulty comp gauge to a melted piston and damaged bore.
I would be very skeptical about the 'idles fine' comment. Are you able to physically hear it running and perform your own comp tests?

 

[hamit59]

Re: Looking at 2001 - 90 hp Mrcury

Well you have fine case to RUN alway from this one. A compression reading of 35 ? There is so many thing that could be bad. I would think it would take at least an over haul. Parts alone would most likely cost you over a grand. ! piston a set of rings main bearings rod bearings and gasket kit seals labor.
If the cylinder is scored look for machine work as well @ 75-100 per hour.

 

[hamit59]

Re: Looking at 2001 - 90 hp Mrcury

Well you have fine case to RUN alway from this one. A compression reading of 35 ? There is so many thing that could be bad. I would think it would take at least an over haul. Parts alone would most likely cost you over a grand. ! piston and rod, 3 sets of rings, main bearings, rod bearings and gasket kit, seals labor.
If the cylinder is scored look for machine work as well @ 75-100 per hour. If the block can be saved.

 

[mikeneal]

Re: Looking at 2001 - 90 hp Mrcury

It better be cheap, cheap enough the motor is free. No way it "idles fine" with 35psi. I have a 99 version of the same motor that is fine mechanically and it idles rough.

 

[StuartT]

Re: Looking at 2001 - 90 hp Mrcury

From the way you explained your thoughts in evaluating this decision, you do not have enough experience with serious engine problems to even consider making an offer on this boat. But if you must, price a new power head on iboats.com, http://www.boatmotors.com/motorparts/, and add $500 to $750 in labor to R & R it. That is the minimum discount you should even consider and even that is being extremely generous. But my best advise ..... walk away.