i have a 1964 merc 500 thunderbolt. has 120 psi on all 4 cylinders. was submerged drained and i took all percations and have been using it for the last two weeks almost daily but now in the last 3 days it lacks power. any ideas what it could be?
Did you clean out the carbs, and fuel system. Was the motor running when it sank? How about the fuel tank, get all the water out? Post back on what you did, its hard to see if you missed a "precaution" if we don't really know what you did do.
Is that a magneto driven ign? And if so did you tear that down? If not take it off, fully diassemble, clean and lube. The bearings may have already been compromised.
The points have to be totally smooth and pit free, and preciously set at .008in
motor was not running when submerged, about a hour after i dropped it i got it drained pulled the plugs out and used the pull start to get the most of the water out used the pull start to get fogging oil throughout. its magneto driven so i ran took it off the motor but did not dissemble. used the air compressor and alcohol to get the water out. put it all back together and she fired up. let the motor run for about two hours and it worked like nothing happened. i rebuilt the carbs and magneto about 4 months ago. its just the last week or so it has lost power
Any moisture left in the magneto may have, over the last few weeks since the dunking, corroded the distributor enough to drop a cylinder or two. Gotta pull it apart to properly dry it out...
