I have a quicksilver propellor with the model number 1916P19 stamped on the side. I know that it's a 19 pitch but not sure about diameter. Seems easy enough to measure but measures slightly larger than 7" radius from center shaft to edge of blade. Maybe 7 3/8. Would thus be a 14" prop? Model number makes me think it may be a 16" and engine performance also gives me this impression. Any advice from the experts out there? Thanks.