i took out a boat that i got from a friend runs great but the throttle piece was broke under flywheel fixed it took it out but the boat want plane out rpms are at about 5000 .was wandering if this engine has advance timing and the piece broke had something to do with this or if its just the wrong prop .. cause the prop looks really new .only number on the prop i could find was f20...... any help will be appreicated...