I was mowing the yard Tuesday and it ran fine for about an hour. When I was about done it kind of sputtered a couple of times and then seemed to run at a lower speed. I was able to finish mowing and it cut fine. When I cut it off (have to cut it off by chocking it) it backfired slightly and a small ball of fire came out of the exhaust. I haven't tried to start it since but I was wondering what this could be? It's a B&S M/N: 422707 I believe. Any ideas on what the deal was/is would be appreciated.

Oh yea, it was about 96 degrees outside when I was cutting. Just an F.Y.I.

Why are you choking it to cut it off?

Kinda sounds like trash or maybe water in the carb. Was the tank near empty?

It has more that 1/4 of a tank.

I'm choking to cut it off because of laziness honestly. I need to hook the kill switch up to it but turning the key off won't stop it. It does start fine with the key though.

I'll check for trash in the carb and let you all know. It'll be Saturday before I can check on it at the earliest.

I was actually able to work on it last night. I took the carb and intake manifold off and blew them out really good with compressed air. I put it all back together and now the engine seems to "surge" constantly. On the lower end of the surge it almost quits running. I noticed that if I choke it, it doesn't surge at all or at least not as bad...

Any ideas on what the deal may be?

Could it be that I need to clean the carb out better?

I just got through tearing it all the way down (the carb) and cleaned it real good. It seems to be running great now. No surging and no sputtering. I also went ahead and hooked the kill wire up and now it shuts off when I turn the key off. Imagine that.

Thanks for the help!!!

Good deal..... does it have a inline fuel filter on it? If not I'd put one on, a briggs oem one.... to filter out any trash in the future.

There is one on there I just put on this year. I'm thinking the trash was from last year. I hope so.

If you choke an engine to death there is risk of backfire. Thats why they put the anti-backfire solenoids on the new engines.

Mike

Not only when you choke it, you risk a backfire when you cut it off at 3600 rpm...... if it doesn't have a fuel solenoid. If it does have one.. it can still happen if you use the seat to kill it.