I would like to adjust the idle on this engine (617.952), but according to the shop manual I need to unattach a pushrod that rises from near the idle adjusting screw to the angle lever at the top of the engine. The manual says to unattach it at the angle lever. I do not see how to do this. Any hints? I adjusted the idle screw first without unattaching the pushrod and it would neither slow down or speed up, so I guess they weren't kidding when they wrote that instruction.

Also, on top of the valve cover is an electronic switch device which has two wires attached to it. This switch seems to be tripped by the throttle assembly whenever the throttle is fully opened. What does this switch do?

Thanks,
Dan