John Deere D140 Running on One Cylinder

[Toledo_Speedo]

I have a 2012 D140 with 145 hours on it; I hit a ball in the yard and snapped the deck belt. I put a new belt on it, got about half the yard mowed, took a break, came back out and it wouldn't start. Plugs were wet so I assumed it was flooded, I let it sit for an hour and it started but seemed like it was only firing on one cylinder. I pulled the left side plug and it wasn't sparking, so I replaced the plug and coil, it will start, bog and die. Any thoughts on what I'm missing?

 

[Toledo_Speedo]

I just double checked to make sure I wasn't losing my mind and I'm not getting spark on the left side of the mower! I replaced the coil and plug, could it be a bad ground?

 

[bertsmobile1]

I just double checked to make sure I wasn't losing my mind and I'm not getting spark on the left side of the mower! I replaced the coil and plug, could it be a bad ground?

Yes it could be a bad ground but more likely a ground that is too good, on the left coil.
Remove then coil kill wires and check each side.
You might like to recheck the old coil as well in the same mannar.
The wire that runs between the 2 coils has a diode in it which goes bad.
The kill wire is a ground wire so if it touches bare metal anywhere it will kill the spark.
I like to use an inline red neon tester as at cranking speeds the sparks can be quite feint and hard to see.
Also a bad plug can track down the side of the inside terminal which you will not be able to see unless in a dark room.

 

[Toledo_Speedo]

Thanks Bert, I'll check that out!