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Considering Joining A Syndicate At Some Point


Ally

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We currently have a Standard Share for sale on Ranworth Breeze.

The allocation dates for 2022 are 24/05/2022 & 18/10/2022 and the allocation dates for 2023 are 06/06/2023 & 24/10/2023.

The price is £4100.00 with the management fees paid by the selling owners.

If anyone requires any further information please contact me.

Regards

Alan

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1 hour ago, Matt said:

I am going to suggest MS’ new engine is in!

Broom Facebook

 

Certainly is.  Brooms have suggested that a larger prop may be required to bring the engine revs down as they believe it’s sitting around 100rpm too high for a given speed, but to try it and see how we get on.  At least it’s not 2000rpm at 5mph!!

No mention of a different pitch or a for bladed though.  Before diving in, I think we need to get the optimum size calculated properly.

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51 minutes ago, Mouldy said:

Certainly is.  Brooms have suggested that a larger prop may be required to bring the engine revs down as they believe it’s sitting around 100rpm too high for a given speed, but to try it and see how we get on.  At least it’s not 2000rpm at 5mph!!

No mention of a different pitch or a for bladed though.  Before diving in, I think we need to get the optimum size calculated properly.

Good luck getting it calculated properly- too many cooks and all that 😃 might just as well ask @oldgregg who called ours pretty early!

Did you leave the gearbox untouched?

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tops out around 2800rpm these days.

Better but still too high for the shaft, plus the donk is not under enough load when cruising, leads to premature engine wear and glazing not to mention taking much longer getting up to correct operating temperature if it ever will during cold winter months, then there is the issue of the domestic water taking an age to get piping hot, again if it ever does

Griff

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I had my props tweaked by clements at little staughton and Paul's calculation was spot on, I told him the boat model and engines/gearboxes and he told what would have been on from new and recommended a slight re-pitch while he was refurbing them, max revs to 3900rpm as volvo spec and the 21-22 knots he predicted.

Refurb and re-pitch was a much shorter lead time than new props and a fraction of the cash, the foundry was where the holdup was, he only had them a week.

 

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I was going to suggest a prop refurb would be cheaper and quicker but Smoggy was faster, if the RPM is only out by a small amount the pitch can often be tweaked.

The engine should reach the manufacturers max rated RPM with the vessel at full load, or as close as possible.  The Nanni has a rated speed of 2800rpm but they may also have a prop selection speed range which could be something like 2600rpm to 2800rpm.  Peachments will know for sure.

 

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NeilB - agree with that (Mostly) I prefer Broads boats on shaft drive to be slightly over-propped so just below max revs achieved but that is just my own preference - Keeps the donk under load, operating temperatures reached quicker and the domestic hot water gets hot quicker too even on short slow cruises in the dead of winter when the river water temperatures are way down

What is not really up for debate is that the shaft speed should not be exceeding 1300 rpm unless direct water cooled of course

Griff

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Slightly under max revs is not an issue on a Broads boat as there's usually a range of RPM the manufacturer will accept, plus it's very rarely going to be run at full chat anyway.

High speed vessels are a little different as they are more susceptible to weight and trim changes plus the builders want to squeeze every last 1/2 knot out of them.  We even strap water bladders to the bathing platforms to simulate a tender and the amount of weight an owner adds, plus I add another 100KG when I step on board.  :default_biggrin:

The other option to water cooling on a traditional stern gland is to fit a rubber shaft seal type, all they need is a smear of grease every 200 hrs / once per year and then they should not leak at all.

I couldn't find the max shaft RPM but the test process was 1000hr at 3000rpm without a single drop of water!

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2 hours ago, NeilB said:

I was going to suggest a prop refurb would be cheaper and quicker but Smoggy was faster, if the RPM is only out by a small amount the pitch can often be tweaked.

The engine should reach the manufacturers max rated RPM with the vessel at full load, or as close as possible.  The Nanni has a rated speed of 2800rpm but they may also have a prop selection speed range which could be something like 2600rpm to 2800rpm.  Peachments will know for sure.

 

According to Peachments, the current setup is within spec, so the warranty on the engine is now applied.  I guess it can’t be that far out then.

We’ll find out more as owners start to use her and report back.

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On 14/01/2022 at 18:40, Mouldy said:

Certainly is.  Brooms have suggested that a larger prop may be required to bring the engine revs down as they believe it’s sitting around 100rpm too high for a given speed, but to try it and see how we get on.  At least it’s not 2000rpm at 5mph!!

No mention of a different pitch or a for bladed though.  Before diving in, I think we need to get the optimum size calculated properly.

If you've got the space then that would be an option - Thunder didn't really have room for a larger diameter prop.

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