I am totally new to this whole forum thing but I am desperate for some help on an old engine. I just replaced the Internal wiring harnes on a type III ( no distributor) 90 hp Mercury motor 1979. The wiring literally fell apart in my hands as I took it off.

After replacing it I have great spark in 4 out of the six cylinders. But the bottom two cylinders (5 and 6) have no spark. I have tested the continuity in all of the wires leading from the stator to the switch boxs and the switch boxes to the coils and coils to the plugs and everthing checks out. Is there a way to actually check the switchbox and if so how??

Also could a single "switch" go out on each box while the others seem to be working fine?

Any help and insight would be much appreciated.

mattzier