My Name Is Jeff Nicholas & I Am A Propeller Junkie

I used to have a Seaswirl 1850.

Back then I was a propeller jumkie - just had to try them all...plastic, aluminum, stainless, 3 blades, four blades, exchangeable hubs and blades, vent holes, high torque, high speed. Here's a few of them.

When I sold that boat I thought my addiction was over. And it was, until I bought my next boat - a 1972 28' houseboat.

This boat has a Volvo Penta Aquamatic outdrive - which is no longer supported by VP. Also the drive is of the 'short hub' variety, which takes exclusively short hub propellers. It's successor, the long hub drive will accommodate either the short hub or long hub propellers. This made me want to be sure I had a spare short hub propeller because the short hub propellers are no longer readily available.

I searched and found very expensive Volvo Penta propellers and less expensive Solas propellers. I opted for the cheaper Solas props and bought a couple of different sizes. 

The trouble was, the Solas propellers weren't a bolt on substitute. I had to modify my short hub mechanics to accommodate the Solas propellers.

Here's what I had to do to make the Solas prop fit

But I wasn't totally satisfied that the Solas props were best, so eventually I bought a couple expensive OEM props. I banged up the OEM props in shallow water, so I decided to replace them with the cheaper Solas props. BUT my source for short hub Aquamatic propellers no longer carried them - they were becoming dinosaurs. I got nervous and looked at maybe upgrading my outdrive to take the later long hub propellers. In that search, I learned the big difference was that the long hub shafts were tapped to take a locking bolt instead of using the familiar bendy tab. I decided to see if I could modify my short hub drive to take the locking bolt by drilling and tapping the shaft.

Here's how I drilled and tapped my short hub shaft.

Now that I had succeeded in being able to mount a long hub prop on my outdrive, I bought a couple long hub props to test. Now I had bocu short hub props and a few long hub props...to test.

Well, now there's more testing to be done. Here we see a 16x13 long hub (top) vs a 16x13 short hub. These are both official OEM Volvo Penta propellers with identical diameter and pitch but the top is long hub and the bottom short. Wouldn't you want to know the difference in performance/characteristics?