phil.s 0 #1 Posted October 19, 2010 I had been having problems with my C121. It would run but as soon as it was put under load or revved hard it would backfire ferociously and die. I replaced the condenser, checked and rechecked the mixture and regapped the points all to no avail. I had been using jump leads off my quad to start it for quite a while now - the battery doesn't hold its charge. After dying it would turn over and start fairly easily. Latterly, I revved it forgetting to remove the jump-leads and it did not die. The penny dropped. The battery was so drained that it wasn't energising the coil. Battery now charged overnight and mower runs perfectly. Hopefully this thread will help someone in future who has ruled out everything else. Share this post Link to post Share on other sites
W9JAB 156 #2 Posted October 19, 2010 :thumbs: Check the valves and adj. as needed! Share this post Link to post Share on other sites
rmaynard 16,327 #3 Posted October 19, 2010 The battery was so drained that it wasn't energizing the coil. Battery now charged overnight and mower runs perfectly. Phil, Are you saying that the low battery was your problem, or are you still getting the backfire? Bob Share this post Link to post Share on other sites
JimD 3,347 #4 Posted October 19, 2010 Battery now charged overnight and mower runs perfectly. Sounds like the battery was the problem to me. :thumbs: Share this post Link to post Share on other sites
