This is my 6th season with this mower. The blades will engage fine to begin with, but cut out after cutting maybe 15 minutes. If you let it sit for at least that long, it will work again for awhile. I have tried to field test overriding the handle "plunger" switch as well as the pull-up engagement knob by attempting to make a connection across the wires using a piece of aluminum that was handy. I know...pretty lame, but I figured enough current might flow to engage the blades. I would appreciate your wisdom in this. Thanks.