Prop Measurement

[sammons]

Can you measure a prop? I have a 1978 140Hp Evinrude outboard that I recently purchased, I'm wanting to buy a spare prop close to the same size as is on it now, the only problem is that I'm not finding any markings on it so see the size or part number. So my question is how or can you measure a prop to find this out? Its on a 17' Robert Hammond (Glastron) v-hull currently im hitting 5300 rpm's at WOT.

Any help would be appreciated... THANKS...

 

[Silvertip]

Re: Prop Measurement

You can measure the diameter but not the pitch. On a three blade, measure from the tip of one blade to the exact center of the prop shaft and multiply by two. On a four blade, measure from one blade tip to the tip of the opposite blade. Diameter is merely the circle the prop forms. Pitch needs to be measured using a pitch block that a prop shop would have. Look at the hub of the prop behind the nut and washer. You will find a part number of something like 13-1/4 x 17 (13-1/4 inches in diameter, 17 inches of pitch).