jack_tar
Well-Known Member
I am looking for a new engine ( outboard ) for a 21 foot yacht. what would be the best size HP 2 or 4 stroke, and approximate price?
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outboard engine size
- Thread starter jack_tar
- Start date
oldsaltoz
Well-Known Member
G'day Jack Tar and welcome to the YBW forums,
Your question is a bit like 'how long is a bit of string"; you need to establish what you plan to use it for.
How often will it be run, just to get off the berth, or longer when the wind drops off, or perhaps motoring some distance to get to open water.
What sort of tidal or river currant will be operating in, this will determine what speed is required to make progress and what rate.
How much noise and vibration can you put up with, 4 stroke is quieter and uses less fuel.
Will the motor be fixed or removable, the total size and weight become a factor if you have to manhandle and stow it.
So, if you can provide a little more information the responses will be better.
I hope this helps.
Andavagoodweekend.....
<hr width=100% size=1> Old Salt Oz /forums/images/icons/cool.gif Growing old is unavoidable. However, growing up is still optional.
Your question is a bit like 'how long is a bit of string"; you need to establish what you plan to use it for.
How often will it be run, just to get off the berth, or longer when the wind drops off, or perhaps motoring some distance to get to open water.
What sort of tidal or river currant will be operating in, this will determine what speed is required to make progress and what rate.
How much noise and vibration can you put up with, 4 stroke is quieter and uses less fuel.
Will the motor be fixed or removable, the total size and weight become a factor if you have to manhandle and stow it.
So, if you can provide a little more information the responses will be better.
I hope this helps.
Andavagoodweekend.....
<hr width=100% size=1> Old Salt Oz /forums/images/icons/cool.gif Growing old is unavoidable. However, growing up is still optional.
snowleopard
Well-Known Member
unless you want to go waterskiing or need something very light to carry around, 4hp is the ideal size. get a lighting coil and rectifier fitted and you can charge your battery too.
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LadyViolet
Active Member
I own a trailer-sailer of similar size to your boat. I use a 6hp four-stroke Mariner, which is virtually the same weight and dimensions as the 4hp but gives me a bit more punch when caught by a foul tide on the Thames. When not in use, I store it in a locker in the cockpit: I can just about lift it in and out without the use of lifting tackle attached to the end of the boom, but I can see that in a few years' time my ageing muscles will need a bit of help.
I am happy with the motor, but don't expect the coil to do much charging on your batteries. I also have a small wind generator and a solar panel.
I think you should budget about £900 for a new one.
Don't ever consider 2-stroke. They might be lighter but they are smoky, temperamental beasts and will break your heart.
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I am happy with the motor, but don't expect the coil to do much charging on your batteries. I also have a small wind generator and a solar panel.
I think you should budget about £900 for a new one.
Don't ever consider 2-stroke. They might be lighter but they are smoky, temperamental beasts and will break your heart.
<hr width=100% size=1>NWS
jack_tar
Well-Known Member
Thank's for the reply. I realized when I posted the question that it was a bit open ended. just wondered what type of reply 's would come in. I have just bought a snapdragon 21. which has a 4 hp yamaha engine. the boat is not yet in the water so I am not able to assess if it is ok. The previous owner seemed happy with it, but my gut reaction would be to have a slightly bigger engine say up to 8HP. As a novice I feel this would help to save any drama during the "learning to sail" process. especially heading into wind and tide. One of the problems will be fitting the engine into the well. I have a 9.9 l/s mercury engine which is just slightly to big. another problem will be choking the engine on its exhaust. I have been pricing 6hp ( new) engines on the phone today but the prices are too high, and there does not seem to be many around s/ hand. apparently everybody wants them for auxilliary engines.
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happyfish
Active Member
Hi I am Also a learner and have a 20 footer(dont mean to boast)
I was also worried and still do worry a little.
I have been getting braver and braver and more confident with my enginen the more i use the boat.
I Have to get out of the river arun witch has a bit of a reputation for its current.
I went out on sat & sun a couple of hours before high tide and the tide was strong.
I was a bit worried and was thinking that i might have to turn around in the middle of the river but Once again the engine done me proud.
I have a New Johnson 4 Stroke 4hp with a internal tank and the optional remote tank fitting. the good thing about this engine is that it is realy a 5hp. they have just put a restriction on the throttle linkage witch you can get changed by your dealer if he's honest. COST £600
The johnson weighs 26kilos witch aint to bad but you must think of other things that add weight to the back of your boat.
1 how many people and thier weight will be at the back of the boat
2 the weight of all your stuff in rear lockers (battery fuel ropes anything) it all adds.
I am finding that my boat is a little to heavy at the rear and it makes it very twitchy to steer out of the river through the chop so I am haveing to add some weight (bag of sand) in the front of my boat.
My Friend has a mariner 6.5hp 4stroke the same weight as mine and it sounds good looks good and has more grunt. BUT £800
To be Honest whatever you get you'll be paranoid about tides and currents and breaking down. it just takes time to get to know your boat and engine and confidence builds very quick.
SO I'd suggest anything between 5 & 7 hp 4stroke depending cost and weight.
Keep the cost down and spend it on safty equiptment for your boat.
GOOD LUCK
<hr width=100% size=1>Sunset smells of Dinner I Must end my tales see you the next quiet place
I furl my sails
I was also worried and still do worry a little.
I have been getting braver and braver and more confident with my enginen the more i use the boat.
I Have to get out of the river arun witch has a bit of a reputation for its current.
I went out on sat & sun a couple of hours before high tide and the tide was strong.
I was a bit worried and was thinking that i might have to turn around in the middle of the river but Once again the engine done me proud.
I have a New Johnson 4 Stroke 4hp with a internal tank and the optional remote tank fitting. the good thing about this engine is that it is realy a 5hp. they have just put a restriction on the throttle linkage witch you can get changed by your dealer if he's honest. COST £600
The johnson weighs 26kilos witch aint to bad but you must think of other things that add weight to the back of your boat.
1 how many people and thier weight will be at the back of the boat
2 the weight of all your stuff in rear lockers (battery fuel ropes anything) it all adds.
I am finding that my boat is a little to heavy at the rear and it makes it very twitchy to steer out of the river through the chop so I am haveing to add some weight (bag of sand) in the front of my boat.
My Friend has a mariner 6.5hp 4stroke the same weight as mine and it sounds good looks good and has more grunt. BUT £800
To be Honest whatever you get you'll be paranoid about tides and currents and breaking down. it just takes time to get to know your boat and engine and confidence builds very quick.
SO I'd suggest anything between 5 & 7 hp 4stroke depending cost and weight.
Keep the cost down and spend it on safty equiptment for your boat.
GOOD LUCK
<hr width=100% size=1>Sunset smells of Dinner I Must end my tales see you the next quiet place
I furl my sails
jack_tar
Well-Known Member
thanks for taking the time and trouble to reply happyfish. good to hear from someone who is at a similar stage on the learning curve. I do not actually have the boat on the water as yet so it is a bit difficult to judge what she will go like with the 4Hp engine. I am hoping to speak with the former owner 2morrow and am hoping that he can give me a better idea of how she goes
cheers jack
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cheers jack
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mark_turner
Active Member
Just a few of points I would say having read the earlier replies:
1. Don't expect a bigger engine to get you out of trouble. If the tide is too strong to make against with a 4hp on 21footer you could end up in just as much trouble with a bigger engine. What gets you into trouble is being in the wrong place at the wrong time. The bigger engine COULD lull you into a false sense of security as it can lead you to leave or return to port when the tide is so strongly against you that you may not have time to bring any back up plan into operation. If your engine stops you will be in trouble. The River Arun in full flood or ebb on a big spring is a case in point.
2 My two stroke is lighter than a four stroke (very important in a small sailing boat where a) the extra weigh can adversely affect the boats sailing ability and b) you will want to take it off and put it back onto its bracket quite often - which can be a danger in itself with a big heavy lump of metal.
3 A two stroke is cheaper, and possibly less polluting overall than a 4 stroke (you don't have to change the oil each year and the amount of oil burnt in just getting out of the harbour is far less than the annual oil change).
4 My two stroke is extremely reliable. No less so than a four stroke I would say.
5 It is important that the engine is well mounted - ie you can reach it and its controls. It doesn't go under when the boat is in a swell or healed. The propeller stays in the water (most of the time at least) - especially when your crew is at the front of the boat. You should also consider how it could be used to help steer the boat – preferably by being suitably mounted ahead of the rudder or, if this is not possible, so that the engine’s own tiller can be used for manoeuvring. It is secure and won't get ripped off its mountings in a heavy sea for example. It may also be important to be able to remove it and stow it in a locker and then mount it on its bracket again in a sea.
6 I am pretty sure that some ports charge lower or no harbour dues on boats with engines of 4HP and below (is this the case for Poole?) so could save you some money.
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1. Don't expect a bigger engine to get you out of trouble. If the tide is too strong to make against with a 4hp on 21footer you could end up in just as much trouble with a bigger engine. What gets you into trouble is being in the wrong place at the wrong time. The bigger engine COULD lull you into a false sense of security as it can lead you to leave or return to port when the tide is so strongly against you that you may not have time to bring any back up plan into operation. If your engine stops you will be in trouble. The River Arun in full flood or ebb on a big spring is a case in point.
2 My two stroke is lighter than a four stroke (very important in a small sailing boat where a) the extra weigh can adversely affect the boats sailing ability and b) you will want to take it off and put it back onto its bracket quite often - which can be a danger in itself with a big heavy lump of metal.
3 A two stroke is cheaper, and possibly less polluting overall than a 4 stroke (you don't have to change the oil each year and the amount of oil burnt in just getting out of the harbour is far less than the annual oil change).
4 My two stroke is extremely reliable. No less so than a four stroke I would say.
5 It is important that the engine is well mounted - ie you can reach it and its controls. It doesn't go under when the boat is in a swell or healed. The propeller stays in the water (most of the time at least) - especially when your crew is at the front of the boat. You should also consider how it could be used to help steer the boat – preferably by being suitably mounted ahead of the rudder or, if this is not possible, so that the engine’s own tiller can be used for manoeuvring. It is secure and won't get ripped off its mountings in a heavy sea for example. It may also be important to be able to remove it and stow it in a locker and then mount it on its bracket again in a sea.
6 I am pretty sure that some ports charge lower or no harbour dues on boats with engines of 4HP and below (is this the case for Poole?) so could save you some money.
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