115 HP Yamaha engine spark problem

hello,
I have a 1987 115 hp Yamaha. I went for a ride on the boat and the engine ran perfect. I went out the next day and only had spark on the starboard side of the engine. I checked the coils, they are good. I disconnected the wiring harness, started the engine and still have the same problem. Any suggestions? Thanks

[boats.net]

Probably a bad pulsor coil, do a ignition test and check the pulsor coils.

full charge on the battery?

We checked the leades of the Pulsor coil to the CDI unit and got voltage on all four leads. We cannot get any voltage from the leads of the CDI unit to the coils ,is there a way to check that? Could it be somthing else besides the pulsor coils? thanks

[dyarbrough]

i have a 2000 model 115 and im having the same problem but it dosent did it all the time only when it wants too