I have a Mercury 1970 7.5hp outboard boat motor. It starts fine, but when i put it in gear and start to increase the throttle, it stalls and i have to let off the throttle to keep it from dying. There is a crack in the fuel pump cover where back pressure from the engine block comes into the fuel pump. I JB welded the crack, but gas still oozes from the crack. Is this the problem? Does the back pressure from the engine increase as the rpm increases? Also a sparking noise is coming from one of the magnetos. I noticed that a post on the magneto was lose, and i was wondering even if the engine ran fine, would i still need a new magneto? Will it damage the engine? Help would be appreciated, thanks.
