Hello all, I have a Makita BHX2500 4 stroke leaf blower that is "gushing" oil into the air filter housing. I assumed that the carb was getting gummed up or had a gasket going out so I just swapped both the carb and gasket to no avail. I can start the blower normally without any issues, the problem occurs if I rev the engine for full power, it goes for about 5-10 seconds and then starts smoking black smoke from the exhaust and putters but still runs and oil starts dripping from the air filter housing. I have pulled the muffler, cleaned the spark arrestor screen and it all looks generally good for being 4 years old. I pulled off the air filter to watch and when I have the engine rev'd after that 5-10 seconds about a 1/4 to 1/2 oz of oil suddenly spurts out one of the screw attachment points that holds the air filter to the carb. I use Makita brand oil that is the manufacturers recommendation and perform annual "tune ups" every spring that includes a new spark plug, air filter, fuel filter, a little sea foam in the first tank of gas. Not sure where to look now, any help would be appreciated!