Solid state coil 35135 8hp Weak spark

[skypilot]

Do these things fail all at once or gradually? All relevant surfaces were buffed clean, tried different plug, tried different (used) coil. flywheel key is OK.
Chipper was unused for3 yrs +/-

 

[Rivets]

Most often they just break down, but they can go gradually. How about supplying us with the model and serial numbers from the engines. COVID has killed our psychic powers and we have no idea of which engine you are talking about.

 

[Hammermechanicman]

"Weak spark" ?
Remove spark plug and use a gap style tester OR put a bolt in spark plug lead and position it 1/4" from engine block and spin engine over. Does the spark jump the 1/4" gap? If yes coil good if no coil is bad.

 

[skypilot]

HM80 155455N 4068D

 

[Rivets]

On those older engines I have found that armature air gap is critical. Try setting the gap to .008”. Second I’m assuming that you have not installed the coil upside down?

 

[skypilot]

Changed the gap to .008 from .013 to no effect. The fire is barely visible jumping the gap on a spark plug. Gotta be something else.

 

[Rivets]

Set the plug gap at .080”. If you lose all spark the coil is going bad and I would replace it.

 

[Rocky J]

Do these things fail all at once or gradually? All relevant surfaces were buffed clean, tried different plug, tried different (used) coil. flywheel key is OK.
Chipper was unused for3 yrs +/-

When you say Flywheel key is ok , did you actually remove the flywheel and look ? This is the last mistake I made on a Techumseh , It looked good from the top, new plug, new coil, lots of sanding and cleaning to end up with a sheared key.

 

[VRR.DYNDNS>BIZ]

Changed the gap to .008 from .013 to no effect. The fire is barely visible jumping the gap on a spark plug. Gotta be something else.

Weak spark is not the problem. If a visible spark, no matter the appearance , you have spark. The appearance is merely an effect of the air in vicinity of the spark. the killovolts necessary to jump the gap are either enough to jump the gap or not enough and no spark.

 

[Hammermechanicman]

I really can't believe how folks over complicate checking for spark. Remove the spark plug and use a gap type tester or stick a bolt in the plug wire and position it with a 1/4" or 6mm from engine ground and crank engine. If the spark jumps the gap the coil has enough energy to run the engine. Color of the ionized air is not important.