Changed the Hydro oil in the B7100 yesterday. Ran it a few minuets, then drained out about a pint to bring it down to the full mark. Has a new fill cap, after it warms up good it starts to leak oil out around the fill cap. Is this a built in breather of some type or is there another breather that may be plugged? Found nothing in either manual about a breather. If no breather why is this happening? Thanks in advance for any info on this.