New Sealine on the river, advice please

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yankeebloke

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Hi All

i am very new to boating and not very experienced, so please excuse if this is a really stupid question.

I have just bought a second hand Sealine 218, (23ft, 205 HP Volvo penta engine)

Now the plan is to have it locally to me, to cruise the rivers (Great Ouse etc) and on occasion take her out to Kings Lynn Wash and do some inshore cruising.

Now my question is this, having taken her out today for the first time, i notice that even the slightest amount of throttle tends not really to increase forward speed, but just bites and raises the bow.

I realise it will not be going fast it all on the river, but anything other than dead slow and i am nose up (i assume because of all the power transfer in the engine)

I have my trim tabs all the way down, and the power trim in to keep the bow down, but i still cant really give even the slightest throttle? nose goes way up and its very hard to see!

with hardly any power, dead slow, bow is down, but steering is all over the place.

Now should i just accept and get used to this? or would adding some ballast to the bow to keep it down (well improve it) be an acceptable solution? or would this then cause me problems when i left the river and went into the inshore / sea areas.

Any body with a motor cruiser on the rivers your advice would be very welcomed, having gone from a 9.9hp dawncraft to this 205hp sealine is bit of a wake up call!:confused:

John
 
Hi and welcome.

Congratulations on your new boat,sure you will get loads on fun with her.
First up your boat is not designed for slow river cruising,but probably 50% of boats on rivers are in the same boat.:).So you are going to have to make allowances in order to use your boat to the full on slow inland waters..There is nothing wrong with your boat it is just that it would be happier flying along at 25 knots and the hull and steering was designed with that in mind.
So you will have to potter along at 5 knots or so (which is normally the legal limit)on most inland navigations.On the river in fresh water keep the trim tabs fully up and the leg practically vertical.You could if you felt inclined bung some ballast in the chain or forward locker to keep the head down a bit this will help a tad to stop the head of the boat blowing around in windy conditions
A 25l water container could fit the bill,a bit of extra water on board is always handy.
However on open water would remove any weight from front of boat.
Basically its 5 knots or 25k and nothing in between,any-who somebody is bound to be along in a min who has actually got one of these and can give some real world advice on where to keep those trim tabs at what speed.

Ps.Buying a new boat is a bit like getting married,does not feel right at first and will take ages to adjust to her ,but in the end,once you get to know her funny little ways,she will pay you back in spades.
 
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She should not really start to raise the bows until 7/8 knots, so you should be able to cruise happily on the rivers at 5 or 6 knots.

I have had 3 cruisers to date, used mainly inland, 22 ft, 25 ft and current 31 ft, all planing boats and happy to cruise at the above speeds.

The smaller boats were single engined like yours, and of course they did wander at low speeds, but you quite quickly adapt to the steering, with a little correction were a joy to use. Your boat will also react to any breeze, but again, unless extremely gusty, you will soon learn to cope.

Good luck and happy boating.
 
Congratulations on your new boat,

We have a Sealine on the Norfolk Broads this one is a 310 flybridge and the one before a Sealine 255

As has been said your boat is not really designed for slow cruising but the benifit you now have you will find the first time you get to open water.

anything above about 6 or 7 mph and the boat will start its transition into a flying machine.

In order to get to the speeds your boat is capable of it must escape the resistance of the water and the only way it can achieve this is to plane (climb onto the top of the water instead of sitting in it). The problem is it will not achieve this till about 15mph, at this speed your boat will act like a motorbike, leaning into the turns and handling like a dream.

The zone from 7mph to 15mph is often referred to as the hump, you should stay well away from this zone as all you will do is burn lots of fuel and make loads of wash. if you are on open water then you push your throttles hard forward at which point your bow will point skywards. dont pull them back until the boat starts to level out again then you can adjust them to your cruising speed.

On the river you will have to get used to fairly vague steering, there is an attachment you can fit to your leg called a ruddersafe which will give you far greater control at river speeds and then lift up under water pressure as speed increases for planing, the smaller the boat the greater the problem, due to your hull shape every time someone moves it has the effect of leaning the boat and doing the same as if you lean a bike, it turns towards the lean, wind and current will also have the same effect but you do learn to live with the set up you have and its apparent mind of its own.

Get out there, enjoy it and look forward to the first time you are able to put the boat on the plane, it is going to make your Dawncraft seem very sedate.

Ian
 
Thanks for the replies everyone, i feel much better, my speed display wasnt working so i dont know actual speeds achieved, i think i know what is wrong with the speed log and will attepmt to fix tomorrow.

i must have already been travelling plenty fast enough, before i went bow up!

Ian, i would like to know more about ruddersafe, i will google it.

Also could someone advise on position of trim tabs and power trim for the river?

at present the trim tabs are all the way down, and the power trim is in, to the bow down position, i assume the is not the most economical position for fuel consumption.

Would i be ok with trim tabs up and power trim set to level?

Thanks again and please keep the good advise comming!:)
 
Our first boat was a Sealine 215, which is the same hull as your 218. They're quite lightly built boats and the bow lifts rapidly at speeds over 6 knots. You'll prob find once your speed log is fixed that was the speed you were trying to exceed. The lightness of build manifests itself at slow speed in that they wander all over the place even if little wind, as you've found out. Best way to steer is as though you're caressing a woman.. sloooow and gentle ;);)

The bow will be quickly blown about by cross winds... don't worry though, you'll soon get to know how she behaves and is excellent for sharpening up your boat handling skills :D I remember once spending 45 minutes holding position outside the locks at Sovereign Harbour on a blustery day with loads of other boats all over the place. I think I learnt more that day about boat handling than any other day on the water, including the days on training courses!
 
yankeebloke said:
Also could someone advise on position of trim tabs and power trim for the river?

at present the trim tabs are all the way down, and the power trim is in, to the bow down position, i assume the is not the most economical position for fuel consumption.

Would i be ok with trim tabs up and power trim set to level?
Click to expand...

You need to keep the leg trimmed right in, anything else at river speed will make it even more difficult to steer a straight course. You only use the leg trim when the boat is on the plane.

The trim tabs will have no effect at all - they are designed to work efficiently when there is a good flow of water over them, so again only effective when on the plane. Leave them in the up position. They work like the flaps on an aircraft, only instead of a flow of air, it is a flow of water over them that makes them work.

To keep speed in the river you will only be pulling around 1100 rpm - any more than that and the boat will start to go bows up as the bow wave makes it's way along the hull as you increase speed.
 
Hi, we pretty much found ourself in the same boat (so to speak) when we bought our Sealine S23. We keep her on the Witham/Fossdyke so are again limited by slow speed limits.

We have found that anything above 1500rpm (KAD32 diesel) and she starts to stick her nose in the air, so have adjusted our cruising to bear this in mind.

As others have said these boats are not designed for river cruising and do tend to wander around a bit. We tend to keep the leg trim at zero and just ignore the trim tabs they wont work at slow speeds.

Have fun with her and if you do make it across the wash at some point give us a shout.
 
yankeebloke said:
Thanks for the replies everyone, i feel much better, my speed display wasnt working so i dont know actual speeds achieved, i think i know what is wrong with the speed log and will attepmt to fix tomorrow.

i must have already been travelling plenty fast enough, before i went bow up!

Ian, i would like to know more about ruddersafe, i will google it.

Also could someone advise on position of trim tabs and power trim for the river?

at present the trim tabs are all the way down, and the power trim is in, to the bow down position, i assume the is not the most economical position for fuel consumption.

Would i be ok with trim tabs up and power trim set to level?

Thanks again and please keep the good advise comming!:)
Click to expand...

Just to reinforce advice above as other have said with a small planing cruiser its either 5/6 knots or 17/18+ anywhere inbewteen is just not possible, bow up wasting loads of fuel.

However trim tabs, run with them fully down on the river, this does cause some drag but not enough to effect speed or fuel consumption, they do however stabilise the hull and stop the dredded outdrive wander lust at very low speeds. On larger boats 25ft+ the effect is much less but it will definately make your 218 steer much better. Try it fully up and down and you will feel the steering get a bit heavier and more positive with the tabs down.
 
I used to have a 215 (same boat but with a grey stripe) and used her at sea and on the river.

Keep the leg trimmed all the way in on the river, this is kinder on the hydraulics and will help ( a tiny bit if at all at those speeds) to keep the bow down.

The trim tabs will have no effect at river speeds so I would leave them up.

Good idea re: the ballast - a few sand bags in the anchor locker will help stop the front getting blown about. NB remove them if going to see so your anchor can be deployed if needed in an emergency!

Congrats on the boat!
 
Just looking at the pics and it looks like there is not enough room to get the second prop in,

Can't understand why they haven't made one yet though, they do make a massive difference on the river.
 
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