How to check Rave valve?

[tripledo]

How do you check a Rave valve? I pulled both to clean them and noticed
that one valve will stay depressed if I close the vacuum line and press the
valve in, while the other valve will slowly release if I do the same. I would
assume this means one of them is not working properly. I have also had a
drop in top rpm to 6,500......would the bad rave valve cause this?

[Technical Support]

It means you have a rupture in the diaphram. We have rebuild kits with new parts for it.