I have not been here in a while and could not locate any of my previous posts so I’m going to start again. Last summer I bought an 01 Honda . The previous owner said the engine had been rebored and a new piston and rings installed. I was using it a few times to plot snow last winter and it started smoking like crazy. I changed the oil and found it to be very thick. Almost like diesel motor oil. I recently had a bit of time an pulled the motor out of the frame where I found one of the cylinder jug bolts to have been siliconed in the whole and the rest broken off in the case. I broke an easy out trying to extract it and had to take it to a machine shop to get it burnt out. From what I can see the interior of the motor looks very clean . The exhaust valve has a lot of carbon on the face and the inside of the port is an oily burnt mess. Any ideas why? The piston and cylinder look good. I checked the crankcase vent to see if it was blocked and it’s not. Could it be valve seals? I really don’t want to split the case if I don’t have to. a guy at a performance shop said to just fill the case with varsol and drain it out and then air dry it and that if it had been swamped that it would clean it that way rather than having to take it all apart.

I also found a crack in the frame which I am prepping for welding. Sorry for the long post. Any help would be appreciated