Stuck float should be easy.
locate the carb, take off the bowl, (bowl nut on carb, ) the float should be level, not hanging down.
fuel pump:
Pretty much, just replace it. They don't make any repair parts for them.
Found this thread reply on another forum, seems to be a common problem with the 610
a dirty carburetor...or a bad float ...or a bad inlet needle.
What is happening is that the gasoline is bypassing the float needle and is overflowing. Then it goes through this passageways and into the oil pan.
IF there is dirt that has gotten onto the needle or seat, this will hold the needle open.
If there is a small hole in the float, then the float will sink allowing too much gas to enter the carburetor. causing this problem.
If the needle or seat has worn or has a chip in it, then the gas will bypass them and flow into the oil.
This is a very common problem.
ALSO, if you have a vacuum operated fuel pump, the diaphram inside the pump may have gotten a hole in it. This will allow gasoline to pass through the diaphram and into the oil supply.