snowbelter 0 #1 Posted January 5, 2011 hello all, my onan ran out of gas after i filled it i have to leave it partially choked to keep it running smooth other wise it hunts,skips and generally runs bad or not at all. any ideas, is the carb. hard to work on any helpful links would be greatly appreciated thanks. Share this post Link to post Share on other sites
buckeye 5 #2 Posted January 5, 2011 I would check the fuel filter first. Running the tank empty can cause the filter to get plugged from all the junk in the fuel tank running to the filter all at once. Share this post Link to post Share on other sites
kpinnc 14,660 #3 Posted January 5, 2011 If I understand what you're saying, the engine "surges" unless you run half or more choke. It's a fairly common problem with Onan Performer engines. If the fuel filter, line, and pump isn't the problem, you'll need to clean the carburetor. The Onan carbs don't have a removable sediment bowl like a Kohler and some Briggs engines. For that reason, gunk that gets by the filter tends to stay in the bottom of the carb body. You can get to both jets without removing the entire carb. Just remove the breather assembly and the top of the carb, and get all the fuel out of the carb body. Both jets are fixed, so there's no adjustment of the top one (#5 below), and you should NEVER remove or adjust the lower jet (#6 below). The lower jet has a plug over it that is just like a threaded plug. Simply remove the plug and spray carb cleaner through it until it is free of gunk and debris. You can remove the top jet with a small flat-tip screwdriver. Use the carb cleaner spray on it until all of the small holes are clear. You'll also want to spray cleaner down into the hole for the jet until it is cleared up as well. When you re-install the jet, just tighten it until it seats in the carb body. Don't "tighten" it down. You can damage the carb and jet if you do. Then just make sure you've got all the gunk and carb cleaner out of the carb body, and carefully reassemble everything. You should see a marked improvement in how the tractor runs. Good luck! Share this post Link to post Share on other sites