I have a PacFac (now Pentair) 50118300 valve on my sand filter.

During the extremely cold weather, I had to backflush my filter, and it is now leaking from the top valve assembly and dripping down the outside of the sand filter housing. I check the sprider gasket and it looks good, so I suspect the o-rings on the shaft of the spider gasket assembly.

I'd like to rebuild the top valve assembly, but I'm not sure how to approach this project give it's spring loaded. Should I remover the pin while the lid is still installed on the valve?

Thanks for the help.