VForce 2 reeds have screws. Interestingly, VForce 2 reeds just say "VForce" on the visible sides of the reed block. VForce 3 and 4 are labeled respectively. I would be very curious how the previous owner came to the conclusion that it needed it. Either he took the reeds out saw a screw was missing and put it back together, or somehow, someway, he ended up with the screw in his hand after it already went through the motor. If it did indeed go through the motor, the head and piston are screwed, and possibly other parts too. Do a leakdown test. If it passes, pull the reeds out and inspect them. I wonder if he meant 1 of the bolts that holds the intake and reeds to the cylinder.