The lift valve (I believe it is called) on my mower has a leak. This is the valve that the lever to lift the mower deck up and down is hooked to. There is a cap that goes over the spring and fluid is dripping from that. There is no gasket on the cap, just held down by 2 screws. My question, looking at the diagram there seems to be an o ring in there (#1 in picture)...anybody ever replace this? Curious on how the spring comes out? Thanks for any help.