Propeller & Cutless Bearing Advice needed

Boheme

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Hi, I have found myself the owner of a Jeanue Sunfast 37, I intend to re-haul her & learn to sail her single handed ( I'm a woman with no previous sailing experience, it's a long story!) i have taken a year out to accomplish the basics, whilst having tuition last Saturday we lost reverse steering due to a sheered woodruff Key. On reading the survey carried out on the boat its recommended that I replace the propeller & cutlass bearing. Although like for like would be straight forward, is there a more efficient product on the Market?? All advice welcome. Thanks for reading
 

vyv_cox

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Cutless bearing replacement is a standard maintenance activity. It is carried out at anything between about 2 years and 10 years, dependent upon the clarity of the water mostly sailed in (sand/mud wears it). It is not a difficult or expensive job.

Replacing the propeller is a different matter altogether. Life of a prop might be 25 years before there is any question of replacing it, although there can be justifications for doing so. What was the reason given?

There are many different designs of propeller. Most will have some particular benefits but all will cost large amounts. At your stage of development I would leave it alone, assuming it is in reasonable condition, until you know exactly what you intend to do with the boat.
 

Tranona

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The cutless bearing presumably has play. It is a normal replacement item and like for like replacement is normal - although there are alternative bearingson the market.

Propellers is an entirely different thing. Presumably your have a standard fixed blade prop which will be sized for the best compromise of motoring performance. There is a vast array of alternative propellers claimed to improve sailing and sometimes motoring performance. They have either folding or feathering blades designed to reduce drag when sailing but still perform when motoring.

In general they are a "good thing" to have, but different designs have different characteristics so you need to be clear about what you are looking for when making your choice - and need deep pockets as they vary in price from just under £1000 to £2500. Personally, I have had a feathering propeller on a heavy old wooden boat which worked well and am just about to fit a folding propeller on a modern boat similar to yours. However, in neither case was it high on my list of priorities and in your position I think I would stick with a standard prop as there are much more important things to spend money on and learn about. Different if the prop has failed and needs replacing as the incremental cost is less daunting than replacing a perfectly good unit.
 

Boheme

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Cutless bearing replacement is a standard maintenance activity. It is carried out at anything between about 2 years and 10 years, dependent upon the clarity of the water mostly sailed in (sand/mud wears it). It is not a difficult or expensive job.

Replacing the propeller is a different matter altogether. Life of a prop might be 25 years before there is any question of replacing it, although there can be justifications for doing so. What was the reason given?

There are many different designs of propeller. Most will have some particular benefits but all will cost large amounts. At your stage of development I would leave it alone, assuming it is in reasonable condition, until you know exactly what you intend to do with the boat.
The reason for replacement of Propeller : heavily pitted, edges crumbling away, lack of cathodic protection. Existing propeller, fixed 2 bladed. Thank you for replies.
 

Boheme

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The cutless bearing presumably has play. It is a normal replacement item and like for like replacement is normal - although there are alternative bearingson the market.

Propellers is an entirely different thing. Presumably your have a standard fixed blade prop which will be sized for the best compromise of motoring performance. There is a vast array of alternative propellers claimed to improve sailing and sometimes motoring performance. They have either folding or feathering blades designed to reduce drag when sailing but still perform when motoring.

In general they are a "good thing" to have, but different designs have different characteristics so you need to be clear about what you are looking for when making your choice - and need deep pockets as they vary in price from just under £1000 to £2500. Personally, I have had a feathering propeller on a heavy old wooden boat which worked well and am just about to fit a folding propeller on a modern boat similar to yours. However, in neither case was it high on my list of priorities and in your position I think I would stick with a standard prop as there are much more important things to spend money on and learn about. Different if the prop has failed and needs replacing as the incremental cost is less daunting than replacing a perfectly good unit.
I shall take your advice and stick to a similar design although the prop does need replacing. Currently Fixed 2 bladed. As you say I have many other expenses ahead of me and £1000-£2000 for a propeller is pushing it. Thanks Gail
 

Tranona

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Yes, a standard prop is about £300+VAT and cheapest folder about £700+ - better ones around £1000. Fit a shaft anode - should be enough.
 

scottie

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If the propeller is a good fit then the key is not required

Kelvin propellers never used a key relying on a correct fit a method that worked for the best part of a century

If you doubt that this works why do so many people have great problems removing propellers

Even so I would always use a key ?

For your new prop I would suggest you look at kiwi props
 
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Sailfree

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Firstly does the manual for your gearbox (I assume its a Volvo) state do not engage reverse to lock shaft?

If OK to lock shaft then sticking with a standard propeller is an option. For sailing there is less drag if shaft is locked - yes I know its counter intuitive! Also locking shaft when sailing reduces wear on cutless bearing. For my Jeanneau with Yanmar engine/gearbox instructions are do not engage reverse apparently it stresses the gearbox /clutch and in fact locks the gearlever in reverse and you have to start engine with it in reverse then quickly go to neutral!

When you do need to replace it a properly sized (for boat/engine) fixed prop gives best forward power but does have drag - its also cheapest option.

If you intend to mostly sail a folding prop is dearer but has least drag and least chance of catching stray bits of rope etc. Disadvantage is less efficient going astern.

If you expect to do a lot of motorsailing a Bruntons variable pitch prop is most efficient but has more drag when sailing than a folding or feathering prop. Great for Med where there tends to be a lot of motorsailing!

If you think astern power is important to stop in a berth or getting off the putty a feathering propellor is the best. Blades are flat so cannot produce quite the forward thrust of a fixed prop but little drag.

Last two are the dearest. Like most things about sailing all decisions are compromises.

After lots of problems with Volvo folding prop I have always gone for feathering Variprop which due to feathering blades does allow me the lock the shaft with the gearbox - reduces cutless bearing wear and does not lock up gearbox.
 
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Boheme

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Firstly does the manual for your gearbox (I assume its a Volvo) state do not engage reverse to lock shaft?

If OK to lock shaft then sticking with a standard propeller is an option. For sailing there is less drag if shaft is locked - yes I know its counter intuitive! Also locking shaft when sailing reduces wear on cutless bearing. For my Jeanneau with Yanmar engine/gearbox instructions are do not engage reverse apparently it stresses the gearbox /clutch and in fact locks the gearlever in reverse and you have to start engine with it in reverse then quickly go to neutral!

When you do need to replace it a properly sized (for boat/engine) fixed prop gives best forward power but does have drag - its also cheapest option.

If you intend to mostly sail a folding prop is dearer but has least drag and least chance of catching stray bits of rope etc. Disadvantage is less efficient going astern.

If you expect to do a lot of motorsailing a Bruntons variable pitch prop is most efficient but has more drag when sailing than a folding or feathering prop. Great for Med where there tends to be a lot of motorsailing!

If you think astern power is important to stop in a berth or getting off the putty a feathering propellor is the best. Blades are flat so cannot produce quite the forward thrust of a fixed prop but little drag.

Last two are the dearest. Like most things about sailing all decisions are compromises.

After lots of problems with Volvo folding prop I have always gone for feathering Variprop which due to feathering blades does allow me the lock the shaft with the gearbox - reduces cutless bearing wear and does not lock up gearbox.
Thank you for your advice, I shall stick to a fixed prop, at this stage in my game drag will not pose too much of a problem for me. Thanks again
 

Talulah

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Firstly does the manual for your gearbox (I assume its a Volvo) state do not engage reverse to lock shaft?

If OK to lock shaft then sticking with a standard propeller is an option. For sailing there is less drag if shaft is locked - yes I know its counter intuitive! Also locking shaft when sailing reduces wear on cutless bearing. For my Jeanneau with Yanmar engine/gearbox instructions are do not engage reverse apparently it stresses the gearbox /clutch and in fact locks the gearlever in reverse and you have to start engine with it in reverse then quickly go to neutral!

Further to your point on not locking the shaft there is discussion here:
http://forums.sbo.sailboatowners.com/printthread.php?t=116625&pp=20
and here:
http://www.ybw.com/forums/showthread.php?t=233033

I have a Yanmar engine but can't remember the make of gearbox.
The OP also has a Yanmar.
 
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ianat182

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Another vote for Hamble Propellors, they manufactured my new prop for the higher speed/changed gear ratio of the new engine I'd installed, and matched to the original shaft taper and keyway.
Very friendly and efficient service. No connection.

ianat182
 
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