No spark right side 425

[smallengineguy]

Hello all, I have a JD 425 with the FC420D engine. It has no spark on the right side. Replaced the coil, still nothing. Can the ignitor run only one side, or is it completely good or bad period? What would the next step be?

 

[StarTech]

Are you sure it is FC420D as that is a single cylinder engine and has only one spark plug. It is more likely you have a FD620D. And yes the ignitor can be half failed

 

[smallengineguy]

Oops, sorry to fat finger. FC620D. I wasn't sure if the igniter could only fire one plug, thanks for the answer. Any other item in the circuit I should be concerned about?

 

[StarTech]

Well you didn't mention that you replaced the spark plug with a known good one. I have seen them to fail under compression load.