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!
If the oil level is correct than maybe one of the two check valves in the crankcase or the reed valve in the oil sump has failed. There is also another check valve in the air cleaner housing.
I don't see it on this parts diagram but it is the one that sits on the backside of the carb, near the engine block.
#5
Fish
I am unfamiliar with this engine, but I might look at the # 58 and #59. Looks like a reed valve setup, and the problem may be around there. But as I said, I don't know much about this puppy.
