Veritas came with a Max Prop feathering propeller. It looked a little sad and showed wear. This is an older model; tried and true. Nevertheless it's prone to wear and made of case bronze. Newer versions (different brands such as Feather Stream and Ewol) are constructed using SS gears that are less subject to wear.
However, to change this now would involve the added expense of a longer prop shaft (and all that goes along with that) in addition to a new propeller. So, for now anyway, the prop is off to be refurbished.
This is the 'Classic' version of the Max Prop, meaning it must be assembled and disassembled on the propeller shaft. Also, because the shaft has been shortened to fit this propeller inside the aperture, there is very little room to fit a puller. The shaft had to be disconnected from the transmission and moved back about 1/4".
Refurbishing is done by PYI Inc, a distributor for the Italian made Max Prop. They are somewhat anecdotal about when refurbishing is needed. However, I did find a PYI blog entry that gave this advice.
"Next thing to look for is play in the blades of the Max-Prop. Engage the propeller in the forward position (straight leading edge stopped angled forward). At this point measure the rotational and fore and aft in the blades. If at the root of the blade you have 1/8” play in any direction I would not expect that the propeller is the cause of a vibration. But if the play exceeds 3/16” or ¼” then the propeller is the likely cause."
Blade #1 - 1/4" rotation
Blade #2 - 1/8 to 5/32" rotation
Blade #3 - 3/16" to 7/32" rotation
It also took several days to clean the propeller properly. This included removing and cleaning the grease out of all the internal parts, using a solvent to remove any carbonized grease and soaking all the parts in vinegar to clean the bronze. Then the exterior surfaces are abraded with 80-grit sandpaper to provide a good surface for anti-foul paint. All the bolt holes were carefully cleaned and chased.
The propeller was then packed and shipped to PYI. They are very polite. It took about a week for PYI to provide an estimate with options. Still the price is high. At one point in time MaxProp was the only good option in the market. Now there are several alternatives. This will be a temporary fix. The next time we will replace the propeller with a newer model.
I'm not very pleased with PYI and I provided them with the following information:
- I am concerned regarding the propeller that I had refurbished by your establishment recently. There are three items that that I consider sub standard. First is cleanliness, even though I specifically asked not to polish the prop it was both bead blasted and polished. Some of the polishing compound was found inside mixed with the grease and in bolt holes. This is frustrating as I had spent several hours cleaning the propeller and preparing the surfaces for anti fouling before sending it to you.
- Secondly, the screw kit provided does not contain screws that match the original screws. I pointed this out to Jerome, however, rather than supplying the correct screws, he chose to tell me this is what is supplied now.
- Finally, after cleaning all the parts thoroughly (again) I find that the prop does not rotate smoothly from forward to reverse.
Frankly, at this cost I expect better work and service than received.
At this point we really have no recourse. We will prepare and install the propeller and hopefully it will work for the next two years.