Propeller size , could someone help me out

[bobs]

Just want to thank everyone for chipping in , all I need to do is get the diameter of my present propeller and don't rely on the numbers on the propeller itself as they are confusing .
Would appreciate it though if someone has the info on hand so I don't need to take a dive and perform some acrobatics under the boat .
Thanks

Regards

[Gruz]

Originally Posted by bobs

Just want to thank everyone for chipping in , all I need to do is get the diameter of my present propeller and don't rely on the numbers on the propeller itself as they are confusing .
Would appreciate it though if someone has the info on hand so I don't need to take a dive and perform some acrobatics under the boat .
Thanks

Regards

That "13" embossed on the propeller stands for 13" or 330 mm, so your propeller diameter is 13" or 330 mm.

…..and what size of the engine you have, 40DS from year 2003 with a 56 hp Yanmar 4JH3E has an original 18*13 prop.


On the other hand why not contact them directly and ask them what propeller size/ diameter they were installing.






https://www.jeanneau.com/en-gb/conta...cy#agency-form

https://www.jeanneau.com/en-gb/contact/

[Jim Cate]

Originally Posted by Gruz

That "13" embossed on the propeller stands for 13" or 330 mm, so your propeller diameter is 13" or 330 mm.

…..and what size of the engine you have, 40DS from year 2003 with a 56 hp Yanmar 4JH3E has an original 18*13 prop.


On the other hand why not contact them directly and ask them what propeller size/ diameter they were installing.






https://www.jeanneau.com/en-gb/conta...cy#agency-form

https://www.jeanneau.com/en-gb/contact/

Are you sure about that? A 13 inch diameter prop for a 56 hp engine seems pretty small to me. I'd be more inclined to believe that it refers to a 13 inch pitch. After all, it is easy to measure the diameter of a prop and not so easy to measure the pitch (for the user, not a prop shop).

Jim

[Gruz]

Originally Posted by Jim Cate

Are you sure about that? A 13 inch diameter prop for a 56 hp engine seems pretty small to me. I'd be more inclined to believe that it refers to a 13 inch pitch. After all, it is easy to measure the diameter of a prop and not so easy to measure the pitch (for the user, not a prop shop).

Jim

OP did not stated engine power, the 40 DS comes with the option of a 40-horsepower engine. according this picture eliche radice have only 13" & 18" tree bladed propellers.

[Jim Cate]

Originally Posted by Gruz

OP did not stated engine power, the 40 DS comes with the option of a 40-horsepower engine. according this picture eliche radice have only 13" & 18" tree bladed propellers.

I read that diagram to mean that those props come in all diameters between 13 and 18 inches. Makes no sense to have only those two sizes... there's a hell of a difference between 13 and 18 inch diameter.

And even if his engine is only 40 hp, a 13 inch diameter seems very small. Our 43 hp Kubota is coupled to a three blade 17 inch diameter Flex-o-Fold via an ~ 2:1 reduction gear.

Jim

[bobs]

My engine is a VP MD22L 50HP and the gearbox ratio is 3 : 1 .
Yesterday a 40DS owner mailed me the specs of his 3 blade propeller , unfortunately he has a VP 55 HP which is an element that also dictates another size of prop.
For sure it's not a 13" diameter prop , that's a certainty .
Yesterday I measured a spare prop. I had on board until last season , but took it - together with more stuff - home to get the overall boat-weight down , I know this spare is smaller that the one on the boat and it measures at least 15" . So my original prop. must be around 17" . No clue of the pitch though .


Edit:
I just , this morning , found out that the bronze alloy Eliche Radice uses is called OTMAN .

The markings on my prop are OT E13 ......catch my drift ?

[Marc1]

I find it disconcerting that you want to guess the size of your prop.

How about a betting competition?
I bet it is 17"

[bobs]

Why do you say that Marc ? I'm not trying to guess , I'm trying to find out .
Isn't that what a board/forum is all about ?
Or maybe you just want people to help you and not the other way around , they have names for that .
I emailed several manufacturers and shops hoping they could give me the info , especially Eliche Radice , but they plain and simply refuse to answer .
This is the world we live in these days , professionals take care of their store , the more info they give the more potential customers use it to their own benefit and find ways to save money .
We mortals are expected to spend money regardless of what .
If I can help people to save some of that money by telling them what I know/think or experienced in the past , and at the same time receive the same courtesy , I consider that as a win-win situation .
This topic and all the others will disappear in to the history of the board but remain googleble , and I think I can speak for most of us that many in one way or the other have enjoyed the help/advise & info found on the net .
Unless you're easely " disconcerted " , in that case it's best to avoid forums , healthwise that is .

Should I now finish with ' AMEN ' before some else does it ?

[Marc1]

Ha ha Bob, great reply. But not practical.
Obviously what you would like, that is someone that can tell you the size of your propeller by way of ... not sure, but it was worth hoping for, is not happening.

You did mention that you could dive under the boat and measure. Is that within your power to do so or is it dangerous or otherwise unfeasible?
Only asking, I would have dived a long time ago, but I am not you.

i can only hope that you can measure the propeller without pulling the boat out of the water or other expensive measures ... or is it measurements ... best of luck, and please ... be more receptive of jokes antics and hoodwinks.
As disconcerting as they may be ...

PS
I still bet it is 17"

[bobs]

Let me give you a few details Marc , I'm north European , my boat is winter stationed in north Africa , the Spanish enclave Melilla to be precise . We are not live-aboards and at the end of the month we start our season by flying over to this different world all together (TIA , this is Africa) .
At the end of May we leave for Gibraltar for a short stop & waiting for a good weather/wind - window to sail to the Canaries .

In December we have been on the boat for 2 weeks , vacation of some sort . I was on my own there for 2 weeks last month . Maintenance , repairs , modification , additions , in other words I had some fun .
The marine we're in is one of the less inviting waters I have ever seen . Hardly any tides , the Med. remember . The prevailing winds are either West or East so the marina rubbish drifts from one side of the dock to the other side , it's trapped .
I haven't seen any water treatment plants so I presume they get rid of their ' waste ' the old fashion Mediterranean way , open sewers .
Although Melilla itself is very clean , unfortunately cannot not be said of the surrounding Morocco .
They have no haul out facilities nor decent workshop to fix a propeller .

I've been diving for 45 years now , in a lot of places , but I refuse to enter waters where you can see the germs lying dormant but ready for their next victim .
Nevertheless I would like this propeller issue to be solved before I get to places where it's impossible or outrageously expensive to tackle the problem .
Gibraltar - I've been there several times - is a place where you can get anything send over , and also have a propeller straightened out .


Now you know why I'm so desperate ( and yet unable to find out myself) to get the correct date so I might even score a (cheaper) replacement whilst I'm still in my own biotope .
If a fellow SO40DS owner by any chance has the right numbers and the willingness to tell me that would be great and very helpful .
And if not , sooner or later ( in clear water) I will get it myself and share it with the community as I've always done on boards after starting a topic .
There you have it .
Can I get out of the shrink's couch now

Regards

[TrentePieds]

bobs:

I know I'm late to the party, but nevertheless: The following link is to a prop size calculator that is used by a great many people on this coast. I have used it myself with excellent results. Plug in the relevant numbers for your boat, and you will be told the diameter and pitch of the prop your boat "should" have. But be aware that because of the many empirical variables in propeller calculations the output from the calculator is a "first estimate" or a "best guess". Nevertheless you will find that the suggested diameter will quite accurately indicate the "swept area" (area of the disc given by the diameter) that is required to absorb the horsepower/torque available at the prop when you are at 80% power. The overwhelming probability is that if your revs have been "normal" in the past, the indicated diameter is the diameter you actually have. The PITCH, however, is not quite so certain. Pitch, however, is easily changed by a firm of "propeller adjusters", if required in light of operational experience, and the "13" stamped on the hub of your prop iis there as guidance for adjusters who may work on the prop in the future.

As Jim Cate said: Diameter is dead easy to determine. Just measure and double the radius on a three-blader, measure the "span" on a two-blader. Pitch is a little more difficult and requires special measuring tools which most of us don't have.

My off—the—cuff guess, without putting numbers through the calculator is that you have either a 16"D x 13"P or a 17"Dx13"P. But here is the calculator:

https://www.vicprop.com/calculator.htm

All the best :-)

TrentePIeds

[bobs]

Ok , here I am with some feedback .
A few days ago I was able to get under the boat and measured from the top of one blade to the center of the shaft , approximately 24 centimetres .
That means 48 centimetres diameter .
Converted to inch I get 18,987 “ .

Measurement was done rudimentary with a piece of wood so there’s an element of error .
It’ s either 18 or 19 “
That means the 13” is the definitely the pitch .
There you have it.

Regards

[Bill O]

Bobs,
By measuring the old prop you are assuming someone actually knew what they were doing when they bought put that prop on Do not make that assumption and buy something similar w/o knowing what should be the correct size.
Not sure if you ran the boat before, but were you able to get to full engine rpm or could you not make full engine rpm (under or over propped respectively)?
As suggested would strongly recommend you use the prop calculators so you get the correct prop. While you had to put personal info in the EWOL site it seemed like it has the most data to correctly give you the size. Yes they want to sell you a prop, but that doesn't mean you have to buy from them. The different prop manufacturers will come up w/slightly different sizes for you boat but if you get enough size "quotes", they eventually will become similar (its not an exact science). The EWOL reply did have other nuggets of things to consider so IMO may as well use there expertise to your advantage.

If you have the cash, why not go for a feathering or folding prop? The drag difference compared to fixed 3 blade is amazing. Besides reduced drag, in reverse you will have less walking (feathering) and when you load up the boat (increasing displacement) you can adjust/fine tune the pitch.
We put a MaxProp on our boat and think it was worth while. If you think the $$ are too much for a new one, ask the manufacturer if they have in house re-manufactured props. Typically they carry a fully warranty but at a reduced cost.


Bill O.

[Marc1]

Why do you say that Marc ? I'm not trying to guess , I'm trying to find out .
Isn't that what a board/forum is all about ?
Or maybe you just want people to help you and not the other way around , they have names for that .

Err ... let's not start name calling just yet.

So the prop is 18 or 19" diameter.
But who is to say that it is 13" pitch?
My prop is marked 18x15.
However it is neither 18 " diameter nor 15" pitch. It is 17 3/4" and 16" pitch

13" pitch is but a guess.

[FPNC]

Hey Bobs,

Radici makes a pretty good propeller and it would be worth having it straightened by a competent shop. The markings on the side of the hub are just model numbers. I am confident that the diameter and pitch can be found stamped into the aft end of the hub under the prop nut and washer.

Remove the prop and take it to a good shop. It will take them about a minute to figure the diameter and actual pitch and to tell you if they can straighten and balance all the blades. If they don't have the answers, go to a better shop.

If it cannot be fixed...buy a new one. If you were happy with the performance of the old prop, buy a new one with the same basic blade design and dimensions. I.E. A three blade with around a 52% BAR (blade area) A Michigan MP3 comes to mind.