Max Prop problem

[Mystic51]

I have a 2 blade Max feathering prop on my Beneteau 331. I have used it successfully for ten years. Yesterday after a day of sailing it would not unfold when we started the engine. We went from forward to neutral to reverse and back quite a few times. We checked to make sure the shaft was spinning while in gear. It did finally unfold but had us worried. The unit was serviced last spring and has worked fine all season until yesterday. We sail on fresh water. What could haver been the problem and how do I keep this from happening.

 

[Jackdaw]

Does your lake have zebra mussels?

 

[Gunni]

“The unit was serviced”, what was done during servicing? Did you do the work?

Dive on the prop with the transmission in neutral. Check it for fouling. Do the blades rotate and set easily in forward and reverse? Any blade wobble.

 

[dlochner]

Does your lake have zebra mussels?

My thoughts.

Or perhaps the prop picked up debris, fishing line, weeds, etc that had to spin off before the prop opened.

 

[Parsons]

Following up on @Gunni 's comment, these props need waterproof grease applied annually or they start tearing apart their little internal gears. PYI sells a kit for $40 (https://store.pyiinc.com/products/max-prop-grease-kit), or you could get it a little cheaper on Amazon. This can theoretically be applied underwater, if you've got strong lungs, don't drop the little grease fittings, and a calm day (don't get conked by your own swim platform). I've known two people that failed on this maintenance and ground up the insides of their $3,000 props (ouch!), making them either freeze or be very loose. Perhaps your 'servicing' covered this, but I'd check.

I'm guessing here, but I doubt the Zebra mussel theory. We've got them in Lake Huron, in spades, and I've never heard of someone freezing their folding prop with them. Correct me if I'm wrong.

 

[dlochner]

I'm guessing here, but I doubt the Zebra mussel theory. We've got them in Lake Huron, in spades, and I've never heard of someone freezing their folding prop with them. Correct me if I'm wrong.

I wasn't thinking of a huge infestation like barnacles on a saltwater prop. I was thinking more along the lines of a piece of shell getting wedged in a spot that kept the blades from opening.

As for servicing, i.e., greasing the prop I now do this in the fall. If there is any water trapped in the hub, greasing will tend to force it out. I also bought 25 of the allen screws, I have about 20 now the rest are lost in the grass.

 

[Rick486]

I hare a 2 blade Max feathering prop on my Beneteau 331. I have used it successfully for ten years. Yesterday after a day of sailing it would not unfold when we started the engine. We went from forward to neutral to reverse and back quite a few times. We checked to make sure the shaft was spinning while in gear. It did finally unfold but had us worried. The unit was serviced last spring and has worked fine all season until yesterday. We sail on fresh water. What could haver been the problem and how do I keep this from happening.

The internal gears do wear after years of use. I sent my 3 blade to PYI after about 7 years and they replaced the crown gear and a couple of minor pieces like cotter pins. They said there was significant wear.

 

[dlochner]

The internal gears do wear after years of use. I sent my 3 blade to PYI after about 7 years and they replaced the crown gear and a couple of minor pieces like cotter pins. They said there was significant wear.

How do you know if the prop needs refurbishing?

 

[Rick486]

How do you know if the prop needs refurbishing?

Well, I felt at the time that after those years of service, around 500 hrs, that I should send it to the manufacturer for inspection and refurb. I did not have a specific gripe. Nor did I notice any change in performance afterward. I just considered it preventive maintenance. I suggest you call PYI and have a chat. They are very friendly and helpful.
Rick

 

[Jackdaw]

Following up on @Gunni 's comment, these props need waterproof grease applied annually or they start tearing apart their little internal gears. PYI sells a kit for $40 (https://store.pyiinc.com/products/max-prop-grease-kit), or you could get it a little cheaper on Amazon. This can theoretically be applied underwater, if you've got strong lungs, don't drop the little grease fittings, and a calm day (don't get conked by your own swim platform). I've known two people that failed on this maintenance and ground up the insides of their $3,000 props (ouch!), making them either freeze or be very loose. Perhaps your 'servicing' covered this, but I'd check.

I'm guessing here, but I doubt the Zebra mussel theory. We've got them in Lake Huron, in spades, and I've never heard of someone freezing their folding prop with them. Correct me if I'm wrong.

I have heard of it, but indirectly. I don't know what prop it was, some are more susceptible to that type of jamming than others.

I know MaxProp's rightfully have their loyal fans, but regular preventive maintenance on a propeller? Wow. Now I like my Flexofolds even more. As the Flexofold site says:
Maintenance : The only maintenance required is to keep the propeller clean.

 

[SG]

Jackdaw: Do you have the Flexofold Gold or other folding two-blade? I certainly think those the two blade folding props to use. I'm not so sure about their feathering props.

Our two blade, feathering Max Prop has been lubed at least every two two years for twenty years. I think we have over 2300 hours of motoring over that period which I'd guess is over 13,000 + nm. We motor at 7.5 - 8+ knots when we're not entering a harbor.

Occasionally, we've had barnacles that caused some issues early in the off years when we don't have the boat hauled and have the bottom repainted. Then, it's never been a blockage of feathering or opening -- it's been a slight vibration issue.

We've occasionally tied-up a lobster pot in Maine or Southern New England, bumped a log, and once tied-up a dingy painter through my error while backing down on an anchor :^))).

If you have it checked occasionally by diver (or if you sense something is off) and lube it every other year, I don't think I'd worry too much about wear. If you slam shift the boat a lot from forward to revers, my view might change.

 

[Jackdaw]

Jackdaw: Do you have the Flexofold Gold or other folding two-blade? I certainly think those the two blade folding props to use. I'm not so sure about their feathering props.

Our two blade, feathering Max Prop has been lubed at least every two two years for twenty years. I think we have over 2300 hours of motoring over that period which I'd guess is over 13,000 + nm. We motor at 7.5 - 8+ knots when we're not entering a harbor.

Occasionally, we've had barnacles that caused some issues early in the off years when we don't have the boat hauled and have the bottom repainted. Then, it's never been a blockage of feathering or opening -- it's been a slight vibration issue.

We've occasionally tied-up a lobster pot in Maine or Southern New England, bumped a log, and once tied-up a dingy painter through my error while backing down on an anchor :^))).

If you have it checked occasionally by diver (or if you sense something is off) and lube it every other year, I don't think I'd worry too much about wear. If you slam shift the boat a lot from forward to revers, my view might change.

The first 36.7 came with a 2 blade flexofold classic folder on the Saildrive from the factory. Loved it so much I bought one for the first 260 to replace the fixed factory prop. Love them.

 

[dlochner]

I have heard of it, but indirectly. I don't know what prop it was, some are more susceptible to that type of jamming than others.

I know MaxProp's rightfully have their loyal fans, but regular preventive maintenance on a propeller? Wow. Now I like my Flexofolds even more. As the Flexofold site says:
Maintenance : The only maintenance required is to keep the propeller clean.

The maintenance isn't all that much. Remove one allen screw, insert a zerk, fill with grease. Repeat for the second set screw. Crawl around on the ground looking for the set screw that you dropped. Takes all of about 10 minutes if you find the dropped screw quickly.

Mine came with the boat, it works well, other props are expensive and I'd rather have new mainsail.

 

[Jerry Clark H356 SV Persi]

You can tell if it needs servicing by holding the blades and trying to wiggle them. If you have play, then the internal gears are worn and need servicing. I sent my 13 season three blade off in 2016 and they refurbished it like new for around $750. Took about a month from taking off, shipping and getting back. Excellent service. Call them at PYI Inc and talk to Jerome Blakey. He’s a pro.