I have a 1978 mercury 70hp merc ( serial #4826566). Just installed new wiring harness,switch bow,stado,trigger,coils & rectifier. Engine cranks but still get no spark. Can someone please help or have any ideas what else it could be.
Welcome to iboats. <br /><br />You might have a mercury switch gone bad. It's mounted at an angle and is intended to kill the motor if the tilt angle gets too high. It has 2 brown leads coming out of it. Disconnect the one that goes to ground and see what happens.
Wiring harnesses can always give you the can of worms, even new ones. Disconnect the harness and jump the starting solenoid with something (screwdriver or large gauge wire) and see if you get spark