Greenhoe valve disassembly and cleaning

[ChadA]

I’ve taken regular rotors apart for cleaning many times. I now have a tenor with a Greenhoe valve. Before I think about pulling it apart, what do I need to know? How different is it from other rotors? I’m most familiar with Shires rotors.

[MTbassbone]

I don't think there are major differences other than the tolerances might be tighter than a standard rotor. Mine was from more than 20 years ago so I don't know if there were changes.

[paulyg]

There are two separate bearing plates, rather than just one found on most rotors. With rotors designed like this (the Instrument Innovations rotor is another), it is CRITICAL to get both bearing plates seated. Otherwise, the spindles will not line up, and the rotor will bind, possibly damaging it. There should be no rubbing on the casing. If you hear a swooshing noise, tap the bearing plates in further.

[brassmedic]

I would say don't even bother removing the back bearing plate. Just leave it as it is and take off just the front bearing plate as you would with a normal rotary valve.