cc, good mechanical sleuthing you've done there. Yes, I agree, all that work is a good idea for a motor of that many years. I'd run the rig without the water separator, too. I didn't see that you are using non ethanol fuel. The ethanol can absorb a little water and do the "drying" for you. Just do as you have been and use fresh fuel each outing.
I've been using Humboldt Hands, a bar soap from Eureka or Arcata California. Our son went to college over there; he stocked us up with lots of bars. They probably have a website.
I run chainsaws for a living, climbing pitchy pine trees, etc. That soap, and Simple Green, cut most of the sticky stuff that I get on me every day.
