Valve repair or replacement.
I've got an old Miwok raft. After two months of patching, and finally re-covering many spots with Flexane, I had the tubes holding air. Then the latest problem cropped up. The glue around the valve boots is failing. This is not particuilarly shocking, the raft is at least 30 years old, but it is irritating. The question is how to repair?
I've already tried regluing just the spots where they've failed. It's difficult to clean the area (these failures, on two tubes, involve about 1" sections of the surrounding patch peeling away from the valve boot), more difficult to get glue in, even more difficult to keep the pieces separated while the glue cures, and the end result is a crappy glue job that fails under pressure.
So I figure I've got two options: (1) remove the valve boots and either clean everything up and reglue or replace and reglue (if I'm going to this much trouble I guess I'd want new boots and valves anyway); (2) install some kind of "donut" patch that covers the old work with some fresh glue and hypalon. The problem with the donut patch is that it would need to fold over the edge of and go inside the boot, since this is the only place there is visible boot to glue to.
If it matters, the valves are the old Military style. They are worn, but still seem to operate just fine.
Any ideas or advice appreciated.