Can't get engine to wind up, is it prop or mechanical, I'm at a loss. Motor has been under water, briefly according to previous, runs nicely. It is a 1965 18HP fast twin, it ran good for about 3 minutes the first time out, 2nd time out lost prop and changed for a used one, some vibration but I need to have the prop fixed, but the motor just doesn't seem to be building the rpms as before. Owner said it wasn't underwater for more than 2 minutes and wasn't running when it went under. I changed one condenser and it fired fine. The prop is same pitch as orginal so it shouldn't have cut my rpms, hope this helps