Yesterday, I started my 1811 cub and it put out an unbelievable amount of smoke! Never did this before. It also would quit after a bit. Spit oil out of the exhaust, too. Badly. What is the most likely problem?
The gas inlet valve in the carb is probably leaking past the needle and seat, overflowing into the crankcase, filling the crankcase with gasoline. Drain the engine oil and expect it to dump lots of gas/oil so have a large catch pan when you do it. Pull the carb and clean / refurbish it, paying specific attention to the float valve condition. Just my thoughts.