You may want to take it a step further if that isn't the problem. You can take an allan wrench and above and below on the body or rotor housing and loosen or take off. It will drop down when loosened, but needs to be just loose enough when the bolts are retightened to allow the rotor to spin. You may have debris in your vane slots which isn't allowing one of the vanes to drop back down.
Robert B [email protected]