bcruik 0 #1 Posted December 26, 2010 Have a 312-8 and engine backfires. Engine runs strong and when it is shutoff and restarted it backfires. I have changed the plug, tried another carb and have cleaned the carbon in the head ( was very little). Valves also are adjusted and the seats are good. I think the timing could be advanced but there is no way to adjust. Any thoughts??? Share this post Link to post Share on other sites
Duff 206 #2 Posted December 27, 2010 First, ! The M12's are notorious for backfiring when you shut them down, especially if you shut down quickly after running them hard, or so I've been told. Both M12's I have need to be left idling for a minute or two after working them or they go off like a deer rifle (scares the h*ll out of my wife and the puppies!) . I don't know of any real "cure", but some of our members who know engines may have some better advice. Duff :ychain: Share this post Link to post Share on other sites
wallfish 15,927 #3 Posted December 27, 2010 Try shutting it off at full throttle. My M16 will pop off every once in a while but not if if turned off at full throttle. I remember reading to do this some where and it didn't make sense to me but it works. Share this post Link to post Share on other sites
dgjks6 6 #4 Posted December 27, 2010 read through this: http://www.wheelhorseforum.com/index.php?showtopic=3780&hl= hope it helps Share this post Link to post Share on other sites