25 hp merc

[jig head]

I have a 25 hp merc with no spark on one cyl.

I switched the green wires on the coils to see if both coils are good and they are so it is somthing besides the coils, plug wire and plugs any thought on what I should check next

 

[oldman570]

Re: 25 hp merc

If the coils are good, then the switch box or stator will be the problem. Try switching the stator wires from the stator to the switchbox. If no change the box is bad. Make sure the plugs are removed from the block and ground them to the block with a piece of wire. If your motor is a point ingnition motor (older than 1976) the above test dose not apply.
Oldman570

 

[jig head]

Re: 25 hp merc

If the coils are good, then the switch box or stator will be the problem. Try switching the stator wires from the stator to the switchbox. If no change the box is bad. Make sure the plugs are removed from the block and ground them to the block with a piece of wire. If your motor is a point ingnition motor (older than 1976) the above test dose not apply.
Oldman570

when you say switch the stator wires. there are a pair of brown wires and a pair of black wires coming from under the flywheel to the switchbox. it is a 1985

 

[oldman570]

Re: 25 hp merc

Sorry, I was thinking you had an older ing. system. If switching the wires to the coils moved the spark to the good cycl. the switch box is bad. The wires from under the flywheel are for the trigger and Ingition stator and operate both sides of the switchbox for both cyc. therefor they are good. First make sure that the magnets on the inside of the flywheel are good by pulling the flywheel and testing with a screwdriver by holding it around 1 nich away from each magnet it should be pulled to the magnets. I have never had a bad magnet yet but anything is possable.

oldman570

 

[jig head]

Re: 25 hp merc

I had the flywheel off and inspected the magnets all looked good.