Hi IBOATS ~ I just bought a used Merc 150 HP Blackmax (2 stroke) from a local guy on CL. He said it was running when taken off and that he just had alot of $$ put into it. Selling it because he got a deal on a 200 hp. When I got it home i found that it was seized. I tried Marvel down all cyls. after I took plugs out and let it sit . Also sprayed WD. Hit the crank nut with impact gun and then breaker bar-no good. Took off heads and the cyl walls and pistons looked great. Sprayed more Marvel- wont budge a hair. The lower unit spins and then goes into FWD and REV. as far as I can tell. I'm thinking the next thing is take off the power head and inspect the crank. I didn't try PB or Kroil yet. Maybe just a case of using a better rust penetrant and letting it sit longer. The marking on the components are from the beginning of last year and the rest of the motor looks great. I git the motor and controls very reasonable and the guy has mutual friends of my brother-in -law so I don't believe he knowingly sold me a motor he knew was seized. I'm thinking it's the crank needle bearings? Hoping that's not the case, but, everything is starting to lean towards that. Any input woul be greatly appreciated. I'll try to post some pics .
