Yardman999
Member
- Joined
- Apr 24, 2019
- Threads
- 3
- Messages
- 17
First Post! Tried the Search function, but didn't quickly come up with the answer.
Background: I'm an experienced mechanic (cars, ...), and have had this Yardman 999 since 1998 (MTD, but built by Kwik-Way). Runs/mows great, with maintenance. Has the original Kohler Command CH22 engine in it.
Battery great, fairly recent new coils, doubt the flywheel key is broken. No fuel/air problems. New OEM ignition switch installed (no change).
First start of the day, cranks great but won't fire. Release the key and it (correctly) springs to the run position. Then often "BOOM!" -- backfire through the exhaust. Not a stuck valve.
Quite convinced that the coils are being shorted somehow while cranking (switch in the START position), but then are active when in the RUN. If I crank briefly and let go of the key, a few times, it will barely start then run fine. I'm guessing a short somewhere?
Background: I'm an experienced mechanic (cars, ...), and have had this Yardman 999 since 1998 (MTD, but built by Kwik-Way). Runs/mows great, with maintenance. Has the original Kohler Command CH22 engine in it.
Battery great, fairly recent new coils, doubt the flywheel key is broken. No fuel/air problems. New OEM ignition switch installed (no change).
First start of the day, cranks great but won't fire. Release the key and it (correctly) springs to the run position. Then often "BOOM!" -- backfire through the exhaust. Not a stuck valve.
Quite convinced that the coils are being shorted somehow while cranking (switch in the START position), but then are active when in the RUN. If I crank briefly and let go of the key, a few times, it will barely start then run fine. I'm guessing a short somewhere?