On a recent trip to Door county my recoil broke, No problem we weren't that far from where we started so we started her up with the spare rope around the clutch and made it back. I took the recoil to the dealer(excellent dealer) and they rebuilt it. The mechanic who usually will tell me anything I ask, said there was a c-clip that broke, I told him I know, I had half of it with me. He said I must find the other half because it could be in by the flywheel,magneto and mess everything up if it happened to be in there and got lodged. I took his advice got the flywheel puller, popped her off and found the piece he was referring to. Put it all back together- the flywheel, recoil, etc. Everything was back together but the exhaust which was off for access to the recoil assembly-I'll call it. We ran out of time the day we were working on it, So I just didn't put the exhaust back together, Which means I did not run it after we put it back together, just pulled it to see if everything was spinning as it should when you pull the rope and it was. Well last night, the night before I am supposed to leave to go up north, I go to put the exaust back together, sealed her everything was perfect. Choked it pulled it three times and she fired up as normal. It only ran for about 5-10 seconds,backfired and killed. Never got it started again, only thing it would do is backfire if we were lucky every 10-15 pulls. I think there is a problem with the timing but I don't know if you guys can help me it would be appreciated.