I have first generation, 2 blade, feathering MaxProp on my N30U. It works great. I am not sure if the previously owner kept up with the maintenance on it. Prior to greasing, it transitions from forward and reverse smooth as silk. I have greased it after each season since, even though it is smooth beforehand.
This time, prior to greasing, I noticed a slight play in the joint. Not in the rotation and transition from forward to reverse, and vice versa. The play is front to back. At the forward and stern of the blade when feathered, is a milimeter, give or take. It may have been there all along and I did not notice it. It might be something new. I attached a video. I would like input as to whether the play is normal, or is it time to replace it?
Send the video to Max Prop and see what they say. I bought NS30U #460 in August with a significant vibration, had a mechanic pull the two-blade Max Prop which was ultimately sent to Max Prop to be rebuilt. The rebuild was $1800. I decided to go with a new thee blade and the boat performs much better and the vibration is gone. You may be looking at the early stages of a needed rebuild.
When I bought La Reina she had a 2 blade MaxProp Classic. It was purchased in 1982 and was one of the first ones the PYI sold. I replaced it in 2019 when it would have had about 2000 hours+ of motoring. It always had a bit of play in it until it was filled with grease. The play in the photo does not look excessive to me but I agree with the idea of sending the video to PYI so they can provide comment.
Thanks all. I sent the video to PYI. They recommended a rebuild. Assuming the rebuild cost will be in the neighborhood of what Dan was quoted, I will probably go with a new one. The 2-blade, 15-inch prop, $2450. The 3-blade is $3100. I will check with Beta (I just received my new Beta 25) and see which they recommend.
Does anyone have experience with the Brunton Autoprop Eco*Star?
I’m interested because they’ve started pushing it as especially good for those of us with electric power, but I don’t know if there’s a real benefit or if it’s just advertising.
Bob,
My boat came with an Autoprop. I switched to a Flexofold 2 year ago, it has less prop-walk, and no maintenance. The Autoprop requires greasing annually, and after certain number of hours its supposed be taken apart and have bearings replaced… so not maintenance free.
Don
There are lots of props you can use. I had a Max-Prop on one boat and it was wonderful except for the price. Back in the day a number of Nonsuches (would have been 30s) installed Auto-Props but a few had problems with engine mounts. The prop was so powerful it wrecked mounts - also pricey. I am a big fan of FlexoFold from Denmark. I only used a three blade but they also make a two blade. As the name suggests it is a folder not a featherer. Cheaper, not cheap. The FleoFold folks in Denmark were great to seal with. The only slight downside with this prop is that it is so efficient that you cannot go dead slow when docking, you have to go in and out of gear to go one knot or so. I have he same situation with my old Volvo saildrive with its three blade folder. Another thing to consider is prop walk. Some props give little or none, with others it can be a problem.
The British mag Yachting Monthly did a comprehensive prop test which should be a must read for anyone looking for a prop.
Bruce-
I also installed a 3-blade Flexofold (last season) and was extremely happy with the performance. The only issue I have is barnacles. Counter to Flexofold’s claims, the higher level of copper in their bronze did nothing to discourage them. I’m just now engaging Flexofold on this topic but would like to know what your barnacle experience was and how you dealt with it. Where I am, in Narragansett Bay, most everyone paints their props, with zinc paint or copper paint.
Thanks,
Dan Weinstein
Look Farther, 30C #205
East Greenwich RI
Don-
I got a 3-blade (Why stick with all the drawbacks of a 2 if I’m investing in a new, low-drag prop). Flexofold recommended a 16’‘x10’’ RH for my particular boat (I recommend using their sizing service- it is part of their quote process, free, and puts the onus on them). The result was 3150 RPM with a clean bottom and no load, down to about 3000 (the max recommended RPM) once the boat was loaded and the bottom got slimy. So pretty much perfect sizing on their part. The only challenge installing was that I had to buy a deep socket of the correct size in order to install, which I wish they had pointed this out in the instructions so I would have known before I started that I couldn’t use a standard socket.
Dan Weinstein
Look Farther, 30C #205
East Greenwich RI
Thanks for the reply and info. I already purchased a 3-blade Flexofold in Feb 2023. The reason I asked about yours was because I was curious about what size they recommended to you. My boat has a 31hp Westerbeke @3000 rpm with a reduction gear ratio of 1:2.13. They told me I should get a 17”x11”, which was in part based on the 17” diameter of my then existing Autoprop. With the new prop I cannot get over 2900 RPM, and engine starts smoking badly at that point. Before I made the purchase, in several emails, Flexofold was quite insistent that this was the correct spec for my boat, and they would not exchange it if they were wrong. So I have kept it, used it for two seasons. But, I feel it is over pitched.
I wonder if there is any way to get them to exchange the blades for ones with less pitch at a reasonable cost?
Here’s what my mechanic says on the size of my three blade Max Prop:
Morning Dan. PYI lists your prop as a 15" x 20RH #2. What that means is 15-in diameter, buy a blade setting angle of 20°. You have to know the direction of rotation of the propeller in forward gear. If it is the exact same engine and transmission combination, then it would be accurate. Otherwise, you have to be sure of all the operating parameters of the engine in order to get the correct data. This is the listing for your prop.
