MalMac 1,332 #1 Posted July 4, 2010 Alright we have discussed this topic to death. I know aleast with mine its all in the carb. I have two 520's, they both have had the same surg problem. One is now fine but the other has got me thinking its time to junk it. I have cleaned the gas tank to where you could use it to store food in it. Put a new gas line and filter on. I have taken the carb totaly apart 3 times and soak it and ran a number pints of Sea Foam through it. I mow 3.5 acres with it. The tractor will do fine for 2 or three mowings then right back to surging. I get it back to the shop pull the top off the carb clean it and it fine. Then it starts again and I start the whole process over again. This is starting to get way past old. Anybody got any Ideas? I think It is time to junk it. When the Onans run they are great but to me they are just to sensitive to diry enviroments. Share this post Link to post Share on other sites
zieg72 209 #2 Posted July 4, 2010 Does the surging go away with a little choke added? If so you have a piece of dirt in the carb plain and simple. My 269H does it from time to time, especially if I run it out of gas by mistake. I can usually clear it by running it full rpm and then applying full choke. I do it back and forth and always clears up after messing with it for a while. Good luck. Share this post Link to post Share on other sites
stevebo-(Moderator) 8,409 #3 Posted July 4, 2010 I found that even cleaning the carb as much as I could did not do it. I bought a new carb on ebay for $100 (new) and it runs perfect now. Save yourself the headache and put a new carb on it if you like the machine. :thumbs: Share this post Link to post Share on other sites
Ken B 3,166 #4 Posted July 4, 2010 Have you replaced the fuel hoses? They could be deteriorating from the inside. Just an idea :thumbs: Share this post Link to post Share on other sites
tranders 0 #5 Posted July 5, 2010 Maybe you air cleaner is allowing too much dirt into the carb. Good luck! Share this post Link to post Share on other sites
rickv1957 73 #6 Posted July 5, 2010 Have you replaced the fuel hoses? They could be deteriorating from the inside. Just an idea This very same type problem happened to me a while back,all the cleaners that I had ran though machine to clean fuel system,made hoses deteriorate in inside,replaced and cleaned everything up ,been good 8 years now,Rick Share this post Link to post Share on other sites
MalMac 1,332 #7 Posted July 5, 2010 Thanks guys for all the suggestions so far. Rick, you might be on to something with the hose's starting to come apart from the inside. I know these hoses are more or less new. I put them on 2 months ago. I have ran a lot of cleaner through them. I was also wondering if you could put 2 fliters on without impeading the fuel flow too much? I think I will put new hoses on and try again. Might have to do what Stevebo suggest. Just worried if I go to and spend money on a new carb I might end up with the same problem. I guess only time will tell. Share this post Link to post Share on other sites
stevebo-(Moderator) 8,409 #8 Posted July 5, 2010 I have 2 fuel filters on mine and no problems with it. Share this post Link to post Share on other sites