It was smoking more than a mosquito fogger. And it has a 96-3 cam if I remember correctly. Long story short the guy who was to loan us a motor never showed so we put one of the engines I brought with me to sell on so we could at least run.A well built Flathead with a billet rod should be able to handle 7300. With a stock class cam it is probably not making much power up there.
With the smoking I would suspect blowby and/or a bad sealing at the breather, bad rubber grommet likely. Much like a crank seal, the flywheel fan blows it every ware. Even a small amount can look like a serious disaster.Oil covered the whole engine and frame of the kart. This was on a Jr sportsman. We were supposed to get a loner clone but the guy never showed. I had brought this flatty to try to sell. We had to set it on a 7 degree mount. We put a gold plate on it with a 49 jet. I only had a 52 and 49 with me. I currently have 6 flathead engines here. It was a last minute throw on the kart and get him on the track situation.
Certainly could be, but changing that seal requires the flywheel being removed. I have been told that the seal can be changed without taking out the crank but I have never tried that. The breather is a simple repair and I certainly would check that first.I agree with Brian on the oil seal. I built a brand new open with brand new seals and the mag side seal leaked and blew oil everywhere.