I just got my first gas motor for a 51 in mono hull. The Mc Culloch has a real weak spark and the piece of trash i bought it from says all large mc cullochs have weak spark. He also swears it is a "new" engine even with the carbon build up on top of the piston. Is there any way to fix the spark or is it really normal.

I have used a mac 32 cc and have never seen a weak spark. The coil probly is bad or a bad plug. The motors are mainly used for largr aircraft because of the high rpm. TRy finding a homelite 30cc. better preformance and you can get parts easier.

you might try to respace the coil. its pretty easy to do. turn the engine over till the coil is directly above the magnet, put a match book between the coil pickup and the magnet, loosen the screws that hold the coil, and let it "suck" up to the match book tight. tighten the screws and your done. you may want to try a new plug also. good luck.
P.S. the Zenoah's or Homelite's would be a MUCH better choice. and the guy you got it from is a stinking LIAR!!

Dose any one know how much rpms mcculloch 32cc has im thinking it around 8,500 or 9,000?