Skeptical i decided to replace the actuator on my own since that was much cheaper and a weak motor seemed more plausible than a binding damper after 20 years

The instruction sheet said the actuator would be shipped in the open position but it also advised you to check for continuity between certain terminals to verify that

Mine came with a small allen wrench hex key for removing the set screw that keeps the crank arm on the motor shaft which was nice

I bought this unit from another retailer