Bill D 2,185 #1 Posted May 21 (edited) I have an Onan P216 that is backfiring when I throttle the engine down to idle prior to shutdown. Any ideas on how to fix this? Hour meter shows only 145. I'm going to clean the carb again, check the float setting and run some older gas out and some Seafoam thru it with fresh gas. Runs good otherwise and idles nicely. KVID0854.mp4 KVID0853.mp4 Edited May 21 by Bill D Share this post Link to post Share on other sites
8ntruck 7,570 #2 Posted May 21 (edited) I'll be watching this, as I have a B&S 10 horse in an Allis Chalmers B-110 with the same issue. I'm guessing that it is carb related. Edited May 21 by 8ntruck Share this post Link to post Share on other sites
lynnmor 7,672 #3 Posted May 21 First thing I would try is removing old fuel and then run it on fresh gasoline without additives. Snake oil will change the mixture ratio of gas to air. 1 Share this post Link to post Share on other sites
Bill D 2,185 #4 Posted Monday at 05:05 AM On 5/21/2025 at 7:17 PM, lynnmor said: First thing I would try is removing old fuel and then run it on fresh gasoline without additives. Snake oil will change the mixture ratio of gas to air. I ran the old gas out. Ran new fuel line, filter and installed a new tank shut-off valve and grommet. I still have to clean the carb again, but the backfiring seems to have stopped. 1 Share this post Link to post Share on other sites
