motox25 36 #1 Posted August 25, 2010 Hey guys I'm new to this forum and am in the process of rebuilding a '91 Wheelhorse 520-H. This tractor has an Onan P220 engine in it. The engine was rebuilt before I got ahold of it and I've discovered multiple problems I've had to correct myself. At first the governor arm wasnt moving at all when the engine was throttled, after taking the engine apart I found a bearing missing that goes at the bottom of the governor arm. This specific bearing is noted in the Onan engine repair manual so I guess its easy to fall out during a rebuild. Now when the throttle is increased I can feel tension on the governor arm as the RPMs increase. This is operating as it should right? Heres my problem, the engine has no throttle range at all. I raise the throttle arm a couple of inches and it runs at the full 3600ish RPMs. lower it to the bottom and it idles. I have both the Onan engine manual and the Toro manual thanks but I still cannot figure this thing out at all. Current configuration on throttle/governor assembly: I have a spring that attaches to the throttle cable arm, the spring is rusted but I don't think this causes the issue, tell me if I'm wrong. This spring can go in 3 holes on the throttle cable arm. Then it attaches to the governor arm and there are 4 holes it can attach in here, I've tried almost all combinations with no success. From the governor arm to the carb is a linkage arm. The governor arm has 3 holes in it and the carb has 2 holes in it. Every diagram I've seen has this linkage in the middle hole of the arm, however my engine races and refuses to idle with the arm in this hole. I currently have it in the farthest hole from the carb (hole facing away from the engine). This arm has a small spring that wraps around the entire arm and has hooks at both ends. This spring is not noted in either manual so I don't know where to hook it up or what its purpose is. The governor arm has a smaller hole in it so I currently have it there and on the other end I have it hooked around the other hole on the carb, I doubt this is right though. Can someone explain to me the mechanics of this governor and post pics if possible. I can post some pics if it would help as well. Share this post Link to post Share on other sites
