Horse Newbie 7,395 #1 Posted June 21 The 1994 520H has developed the dreaded Onan surge the last day at The Big Show. I already know from here and so helpful people at the show that I can try taking the top of the carb off and clean the carb with carb clean. Problem is stupid me did not bring any tools and a lot of people are packing up and leaving.( And I’m a rookie ) I can get it to stop surging if I close the choke slightly. Will running it with the throttle partially closed hurt anything ? Any ideas for a simple quick fix so I can ride it this last day, until I can get her home and dive deeper ? IMG_5431.mov Share this post Link to post Share on other sites
lynnmor 7,799 #2 Posted June 21 (edited) There is a welsh plug just above the idle mixture screw on the muffler side of the carburetor, check if it might have fallen out. Yes, it is hard to see but a flashlight can help. I wouldn't run it if the plug is out due to dust getting in. One more trick is to go full throttle and then push the choke full on for a second in an effort to clear debris. Edited June 21 by lynnmor 1 Share this post Link to post Share on other sites
Bill D 2,246 #3 Posted June 21 Sorry Tim. I don't know of any quick fixes with out tools. I'd be concerned about losing some small parts in the grass as well when trying to fix it. Share this post Link to post Share on other sites
lynnmor 7,799 #4 Posted June 21 This is what you are looking for: Share this post Link to post Share on other sites
squonk 43,735 #5 Posted June 21 Just for the heck of it, Try running a heavy dose of Seafoam thru the gas tank. It worked on my 520 1 Share this post Link to post Share on other sites
76c12091520h 3,894 #6 Posted June 22 Agree with @squonk 100% here; I am absolutely not a mechanic in a can kinda guy, but that stuff ( Seafoam ) DOES work very well at straightening out the dreaded Onan surge. 1 Share this post Link to post Share on other sites
