My propeller

crown22

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New to me boat lifted yesterday after between 3 to 5 years on Lake Windermere. Was towed for liftout by Maiden Marine who did a great job for me. Good job I arranged the tow looking at the prop.Does anybody have any idea of what has happened to it?Was on a swinging mooring but still has anode on from when it was last in a marina.Any ideas on a replacement i.e is it LH or RH bronze or some other metalcsprop.jpg?Thanks in advance.
 
That almost looks as if it has been cut down from a larger prop. Corrosion is not usually quite so clean at the edges.

RH prop.

If you can get it off, there may still be maker's marks and ID for size stamped into it. Your best bet is to post the type of boat, size and make of the engine, and someone will give you the pitch and dia needed for a new prop. Oh yes, you will need to measure the dia (and taper if any) of the shaft.

It is very possible if an anode is not connected properly that it just sits there doing nothing.
 
Thanks Sarabande
Colvic Sailer 26 approximately 6500lbs with Lombardini 702M 18HP at propeller.The engine has its own internal zinc anode which I will be checking next.When I first saw the prop I thought impact damage first then chemical action second. Didn't occur to me that somebody had sawn off the ends of the blades.No other evidence of chemical attack on the other metal below the waterline.
 
It is an Axiom propeller www.axiompropellers.com It is meant to be shaped like that. Most commonly used on narrow boats but they did attempt to enter the auxiliary market a few years ago - without much success. The person who fitted the Lombardini was obviously seduced by the claims made about it. Quite an unusual choice, a Lombardini and an Axiom prop!

Not sure whether the conventional calculations for prop sizes works for that design, but the size will likely be stamped somewhere on the boss. Suggest you contact them for more information.
 
The Axiom prop was included in YMs famous 2009 folding propeller test (even though it is a fixed prop.) The comments seemed to be that it had very good astern thrust/stopping power ( though it was being compared with folders) and was best for low prop walk, unfortunately forward thrust which is also quite important seemed to let it down, the test is still available.
 
That almost looks as if it has been cut down from a larger prop. Corrosion is not usually quite so clean at the edges.

RH prop.

If you can get it off, there may still be maker's marks and ID for size stamped into it. Your best bet is to post the type of boat, size and make of the engine, and someone will give you the pitch and dia needed for a new prop. Oh yes, you will need to measure the dia (and taper if any) of the shaft.

It is very possible if an anode is not connected properly that it just sits there doing nothing.

It could be a LH prop if the shaft turns the other way like mine does on my Bene!
 
The Axiom prop was included in YMs famous 2009 folding propeller test (even though it is a fixed prop.) The comments seemed to be that it had very good astern thrust/stopping power ( though it was being compared with folders) and was best for low prop walk, unfortunately forward thrust which is also quite important seemed to let it down, the test is still available.

PBO subsequently tried one on I think a CO26 also with a Lombardini and found little difference from the standard prop.
 
It is an Axiom propeller www.axiompropellers.com It is meant to be shaped like that.

I wondered about that when I saw the picture, but I am less sure now. Is one blade much smaller than the others? It certainly could be an Axiom, but I think Sarabande's theory of something bigger cut down has a lot in its favour too.

The Axiom prop was included in YMs famous 2009 folding propeller test (even though it is a fixed prop.) The comments seemed to be that it had very good astern thrust/stopping power ( though it was being compared with folders) and was best for low prop walk, unfortunately forward thrust which is also quite important seemed to let it down, the test is still available.

As I understand it, the point about an Axiom is a completely symmetric, or almost completely symmetric, blade profile, so unlike most props which have blunt leading edges and fine trailing edges it should work as well in reverse as forward. The trouble is that part of that is achieved by not working as well in forward as an asymmetric prop ...

For a comparison with "no loss of thrust in reverse", see Dyson's claims that their vacuum cleaners show "no loss of suction" while being very careful not to say how much suction there is for none to be lost of ...
 
The blades look flat and symmetrical. I think the "small" blade is an optical illusion. Diameter looks about right for the size of engine.

Wait to hear more from the OP.
 
In that case, what does the OP mean by "what happened to it"? :confused:

Richard

It is not clear whether he is talking about one blade as he talks about sawn off blades. The two blades that are clearly visible look sound and do look like Axiom blades.

As suggested earlier more information from the OP would be useful.
 
It could be a LH prop if the shaft turns the other way like mine does on my Bene!

:sigh:
Only a retired politician could countersay the evidence of eyes.

https://www.deltaservicedieselengines.com/en/18-lombardini-engine-ldw-702.html

Rotation is counter-clockwise. It is standard that is viewed from the front of the donk. Post hoc, ergo PROPter hoc (see what I did, :sigh: again ) output shaft will rotate, unless the HURT HBW50 is a very strange HBW50, clockwise when viewed from the aft end..

I think your engine is in back to front and your gear shift is mis-labelled Astern for Ahead.
 
If it has been in the water a few years, have you noticed a drop off in motoring performance? Difficult to tell from the photo but if one blade is considerably smaller than the others then you would have noticed considerable vibration underway.
 
:sigh:
Only a retired politician could countersay the evidence of eyes.

https://www.deltaservicedieselengines.com/en/18-lombardini-engine-ldw-702.html

Rotation is counter-clockwise. It is standard that is viewed from the front of the donk. Post hoc, ergo PROPter hoc (see what I did, :sigh: again ) output shaft will rotate, unless the HURT HBW50 is a very strange HBW50, clockwise when viewed from the aft end..

I think your engine is in back to front and your gear shift is mis-labelled Astern for Ahead.

It does look like a clockwise / righthand prop to me. :o

Richard
 
It is not clear whether he is talking about one blade as he talks about sawn off blades. The two blades that are clearly visible look sound and do look like Axiom blades.

As suggested earlier more information from the OP would be useful.

I think the reference to sawn-off blades was just a response to Sarabande who has mis-identified the prop and thrown a red-herring into the mix. ;)

Richard
 
:sigh:
Only a retired politician could countersay the evidence of eyes.

https://www.deltaservicedieselengines.com/en/18-lombardini-engine-ldw-702.html

Rotation is counter-clockwise. It is standard that is viewed from the front of the donk. Post hoc, ergo PROPter hoc (see what I did, :sigh: again ) output shaft will rotate, unless the HURT HBW50 is a very strange HBW50, clockwise when viewed from the aft end..

I think your engine is in back to front and your gear shift is mis-labelled Astern for Ahead.

Why do insults? Anyway the vast majority of engines turn clockwise looking from the front. My Bene does have a left hand prop, there are big letters stamped on it LH, the shaft turns anti clock wise looking at it from astern! So farmer boy, carry on doing what you do with your sheep! Ooh, see what I did there!
ps :)
 
It does look like a clockwise / righthand prop to me. :o

Richard
Richard,
Not having a pop at you but " As I understand it, the point about an Axiom is a completely symmetric, or almost completely symmetric, blade profile, so unlike most props which have blunt leading edges and fine trailing edges it should work as well in reverse as forward. The trouble is that part of that is achieved by not working as well in forward as an asymmetric prop ..."
So apparently they can be used either way?
I also did do a lot of qualifying in my answer, Tim should learn from an ex politician!
 
So, on the basis that your Bene has a LH prop, you state the OP's prop "could be" a LH. He posted a clear picture for goodness' sake ! You had two choices, and got it wrong.

And as for insults, try saying farmer boy to my face. And it takes a windbag ex-councillor from LLanfairgoodnessknowsonly to know what illegal acts can be committed with sheep. Now run along and winge to teacher.
 
So, on the basis that your Bene has a LH prop, you state the OP's prop "could be" a LH. He posted a clear picture for goodness' sake ! You had two choices, and got it wrong.

And as for insults, try saying farmer boy to my face. And it takes a windbag ex-councillor from LLanfairgoodnessknowsonly to know what illegal acts can be committed with sheep. Now run along and winge to teacher.

Oh dear me!
If that prop was turning the other way it could act as a left hand prop. It all depends on the rotation because according to the person I quoted said, they are designed to drive both ways.
As for insults, you started it!
Need to take a chill pill?
 
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