Max Prop

[tfields]

We recently had a Max Prop installed on our 450 Hunter Passage. The yard indicated that they had a good deal of experience with this prop and set the pitch to the maximum. We find that the boat will not run any faster than 5.8 knts with the throttle wide open, and I am assuming that the pitch is set to high. Does anyone have experience with this prop and our boat? Does anyone have any recommendations regarding the pitch setting to achieve the best balance of performance and power? Can the pitch be adjusted with the boat in the water and the prop mounted in place?

[Fstbttms]

Originally Posted by tfields

Does anyone have any recommendations regarding the pitch setting to achieve the best balance of performance and power? Can the pitch be adjusted with the boat in the water and the prop mounted in place?

Yes, a qualified diver can adjust the pitch of your Max Prop while it is on the boat and in the water. Contact PYI for a local diver referral and also for the correct pitch setting for your boat/prop/transmission combination.

http://www.pyiinc.com/index.php?sect...tion=main&sn=1

[CapnHand]

tfields, What was your top speed with the old prop? What rpm does / did the engine run with 'throttle wide open' now and before the max prop was installed?

[svindigo]

We have a MaxProp and installed it with the PYI recommended settings. We ended up being underpitched (could overrev the engine without matching our old speed) We increased the pitch(twice if I recall) until the engine topped out at the manufacturers recommended top rpm. We cruise at about 75% of that speed. If you were overpitched I would think the engine would be laboring more. When we bought our prop there were 2 models, 1 your change the pitch in the water and 1 that you had to haul out to change. If you are lucky you have the former and can experiment until you get the results you are looking for.

Ike

[mallo]

Originally Posted by CapnHand

tfields, What was your top speed with the old prop? What rpm does / did the engine run with 'throttle wide open' now and before the max prop was installed?

Also what was the pitch and size of your old prop, gearbox details, engine size etc?

We have one, its brilliant, not quite as good speed motoring (down by ˝ knot) but far superior for sailing, wouldn’t be without it.
Suppose we were lucky with original.
It can be altered afloat, not a very easy job it can be fairly fiddly depending on which model you have.
I have fitted a number of them over the years used the settings supplied by the manufacturer and several of them we changed the settings, including our own (we played around with the settings a few times till we were happy with it).
We dried the boat out easily in each case, easy with 40ft rise and fall in the tide!!

[Fstbttms]

Originally Posted by svindigo

When we bought our prop there were 2 models, 1 your change the pitch in the water and 1 that you had to haul out to change. If you are lucky you have the former and can experiment until you get the results you are looking for.

Any Max Prop (or any folding or feathering prop, for that matter), regardless of model, can be serviced underwater. The yards will not tell you this, for obvious reasons.

[svindigo]

Thanks for the tip!

[Valiente]

So can any VariProp, with the added benefit (to my mind, at least) that you can have different pitches for both forward and reverse. When you have a full keel and a wind on the beam, these things matter.

[k1vsk]

Just to clarify, only one model MaxProp can be EASILY re-pitched under water. Although it is possible to re-pitch the older ones too, the necessary partial disassembly is prone to create problems even if done expertly simply because people work better on dry land than under water. I'd be suspect of anyone that gives you the "no problem man" response.

[Fstbttms]

Originally Posted by k1vsk

Just to clarify, only one model MaxProp can be EASILY re-pitched under water. Although it is possible to re-pitch the older ones too, the necessary partial disassembly is prone to create problems even if done expertly simply because people work better on dry land than under water. I'd be suspect of anyone that gives you the "no problem man" response.

No offense, but since you have never re-pitched a Max Prop underwater, you are unqualified to asses whether or not doing it that way is "prone to create problems." I have personally removed, installed and re-pitched many, many Max Props underwater with a 100% success rate. Is it a job for somebody unfamiliar with the procedure? Probably not. But PYI (the U.S. distributor for Max Prop) will unhesitatingly recommend qualified divers to Max Prop owners for underwater servicing of their products. The inference that in-water work on these props is a risky or shady undertaking is simply inaccurate.