Does anybody have any ideas?? I have a 1968 mercury 50hp. s/n 234555 it starts and runs fine for about 45min. to one hour then it just shuts down [like someone just turned off the key ] it will then crank over but will not re- start because it has no spark. after a long cool down [several hours] it will start back up and run fine. also it seems to shut down when the motor is running wide open or at a high RPM speed. I changed out the main coil wire last week and still the same problem ! ANY IDEAS ???
