papasan1 4 #1 Posted May 23, 2014 I probably messed up and posted in another forum. Purchased a 520H and changed all fluids and filters. Running fine. Next day changed the spark plugs. Now it won't idle, rpms flutuate and will run full throtle with the choke 1/4 closed. I put the old plugs back in...same thing. What could I have possibly screwed up? Thanks, Frank Share this post Link to post Share on other sites
boovuc 1,090 #2 Posted May 24, 2014 I answered the post in the main forum but here it is again. Most of the time, when you see that fluctuation and you need to choke it some to smooth it out enough to idle, your looking at some debris in the carb. It was most likely a coincidence it started after you changed the plugs. Especially if you put the old plugs back in it and had the same result. Share this post Link to post Share on other sites
Martin 2,130 #3 Posted May 24, 2014 You have junk in the carb, search onan carb clean on here, there are many posts on the subject. I have some info in my 416 adventures thread as well....... Sent from my iPhone using Tapatalk Share this post Link to post Share on other sites
papasan1 4 #4 Posted May 24, 2014 Thanks for the rapid response. I'll go looking in the carb. Share this post Link to post Share on other sites
papasan1 4 #5 Posted May 26, 2014 I took off the top of the carb, rermoved the float and needle valve, used carb cleaner in every hole, blew out with air...PROBLEM SOLVED111 Thanks again to everyone. Share this post Link to post Share on other sites