31c707 0154e1 engine

I’m having significant oil blow out the exhaust. Head gasket was fine. Replaced the head gasket and intake valve rod seal a year ago. It seems the cylinder rings are the culprit but what’s odd is had no smoke when I used it last and then next start it smoked like crazy and idled really rough. The quick difference made me think it was a gasket but there is quite a bit of oil in the cylinder, maybe a 1/2 a teaspoon. No gouges or really and marks in the sleeve either. 🤷‍♂️

Wish you did a leak down test before pulling the head. Also have you checked the oil level?

So the full story is this. Changed the oil a week ago and mowed my front lawn.Did 2 laps around the back and my transmission front mount bracket (torque strap) broke and bc of life w 4 kids and issues w parts being delivered, the lawn mower sat out there for 1 1/2 weeks. Rained a couple of days in there. Got the part, pushed the lawn mower into the garage and replaced it w no issues. Started it up w no smoke or issues and parked it in the shed. I pulled it out to clean out the shed and parked it. Went to put it back in but wouldn’t start, seemed the battery was dead so I put the trickle charger on it over night. Now my lawn mower has this refurbished engine in it and the guy who did it put in an inline fuel shut off bc the carb float didn’t work I guess. So ended up it wasn’t the battery, I had left the shut off in the on position and gas gravity fed down and flooded the cylinder which then locked it up from turning over( it’s happened like 5x in the 3yrs I’ve had it) so it had gas sitting in there for a day. Figured that out, pulled the plug, cranked it to blow out the gas, reinstalled the plug(which also looked great). Started right up but had the thick oil smoke immediately, let it run like that thinking it just had some residual gas/oil to burn off. It got a little better but still spewing smoke and sounded really rough. Btw w the piston head about 1/2” back from tdc I was able to rock the piston head back forth a little bit, seemed like way too much play in the rings but I have little knowledge on clearances on these small engines.
Sorry for the lengthy story, thanks for your patience!

With the cylinder flooded the crankcase will be as well. Change the oil.