J/30 Class Association Forums J/30 Forum The Boat, Sails and Equipment Martec Folding Prop

Martec says it should open at 600 RPM's?? Just pop open??
The boat moves foward under low RPM's,but with little power and then it rumbles at the shaft at higher RPM's(1,800) and finally opens up and powers out.
Does your boat do this??