Have you replaced the rubber diaphragms inside the RAVE valves and made sure the garter springs are intact and the bellows are firmly attached to the Rave valve posts too, at the small end of the diaphragm
I have not. I just bought the housings, diaphragms and new gasket and o rings. Going to start with everything new except blades because I’m not comfortable shaving them down to match the pistons
I had a similar problem with mine. initially replaced o-rings, then bellows... It ended up being the housing and/or valve shaft was worn resulting in blow-by.
I just replaced everything (housings, valves, gaskets etc...) and problem solved.