Chris,
Glad your back up & running. What are you using for chemicals. You may want to change over to all volitale water treatement. Using phosphate you may be carring over. Next ouytage inspect your dryers in both drums. Get sodium analyzers installed pronto. Good luck mate.
Remove the disc and or replace the rotor is what is usually done. Get your steam sodium analyzers functioning or installed once you replace the rotor. Sounds like you have problems in the boiler carrying over. Good luck Mate.