The rear "seal" is just an oil slinger. Some oil gets by and that is why Henry made the drain hole with the big cotter pin to keep the hole open. Make sure you are not overfilling the crankcase. 4 quarts. 4 1/2 if you have a filter. John
Well, I hope I haven't started the oil capacity thing again. If I don't change the filter, 4 qts brings our 46 to the full line on the dipstick. John