What size engine, horse power, for coastal and river cruising?

S

Schmoo

New Member
Joined
27 Sep 2021
Messages
5
Visit site
I'm new to boating. I'm looking for a boat of around 30 feet (more or less) that is capable of some coastal cruising, also some rivers and possibly canals, depending on bridge clearances and draught. My budget is 20 to £25,000. My question is - What would be the minimum recommended engine size? I'm looking for a diesel engine due to fuel availability, and consumption.

I've looked at a couple of Fairline Mirage 29's, which I liked. The one I liked, had twin 75hp diesels and the broker thought that might be too small for coastal cruising/sea use?

I'd be very interested to hear peoples opinions on what they think the minimum size engine I should look to buy in a 30 foot GRP hulled cabin cruiser. Also any recommendations of a boat type/make? Thanks in advance
 
Air draught is perhaps more of a constraint on canals
The twin 75hp Volvos possibly on stern drives are getting a bit long in the tooth
 
scottie said:
Air draught is perhaps more of a constraint on canals
Click to expand...
(y)
And beam.

I think you might struggle to find something that would fit in most canal locks and still cope with wind over tide in the Solent or the Thames Estuary. I also wonder if you won't find that engines with enough power to deal with coastal cruising wouldn't suffer at the throttle settings you'd use on an inland waterway
 
Hmm, yes you'll get better advice from the mobo forum but here's my take - there are few boats that you could potentially use on canals as well as river/coastal. One that springs to mind is Viking (26/23), more often than not outboard powered, friend of mine had one in our coastal marina, I did some work on it for him which revealed to me how flimsily/badly built they are. Inland waterways are speed restricted so if you envisage that's where you'll do most of your boating I'd look for something with a couple or one diesel modestly sized (couple of 30/40hp engines, say, in a 30 footer) engine(s) on shafts rather than outdrives, mainly for easier maintenance. With such a boat you'd be able to do some coastal cruising, at modest speeds (say 5-10 knots) in relatively calm conditions and making allowances for wind/tides. You can coastal cruise in just about anything (and people do) in the right conditions, it's when you have to go against the tide, when there's wind over tide or the weather turns unexpectedly that you need sufficient power to get out of trouble. Boats that would fall into the above category however are few and far between, they'll mostly tend to have more powerful engine(s) than that. If you envisage mostly coastal use I'd look for more power, again if it were me I'd look for shaft drive rather than outdrive but that's just what I know & prefer. Try to get an idea of fuel consumption of anything you're considering, the figures for boats that travel at faster speeds (15/20/25 knots) through water can use an eyewatering amount of fuel...
 
'some rivers and possibly some canals' needs to be refined, some canals have locks only 7ft wide, others are wider.
There seem to be a lot of people with seagoing type motor boats on the non-tidal Thames.
Likewise the Severn.
Some people cruise quite extensively in quite slow semi displacement motor boats. You don't have to do 30knots to get to France, it only takes a day from Chichester at 6 knots.
Equally there are many river boats I'd be nervous to take on most tidal waters.

Like most sailing boat people, I find the fuel costs scary when you start talking about big engines and/or going fast in substantial boats.
But a lot of people enjoy owning such boats without doing ever so many miles or engine hours, the fuel may not be significant compared to moorings, depreciation, insurance, engine servicing etc etc.
 
Schmoo said:
I'm new to boating. I'm looking for a boat of around 30 feet (more or less) that is capable of some coastal cruising, also some rivers and possibly canals, depending on bridge clearances and draught. My budget is 20 to £25,000. My question is - What would be the minimum recommended engine size? I'm looking for a diesel engine due to fuel availability, and consumption.

I've looked at a couple of Fairline Mirage 29's, which I liked. The one I liked, had twin 75hp diesels and the broker thought that might be too small for coastal cruising/sea use?

I'd be very interested to hear peoples opinions on what they think the minimum size engine I should look to buy in a 30 foot GRP hulled cabin cruiser. Also any recommendations of a boat type/make? Thanks in advance
Click to expand...

I suggest you look into which rivers you have in mind as there are not really very many in the UK. As for canals the restriction would be bridge clearances as well as depth of water and width of the locks. Few boats are happy on both rivers and canals.
I am sure 2 x 75hp is okay as long as you are happy to go slow.
A single engine would be more economical . Something like a Nimbus 27 Famillia with a single 130/150hp perhaps? Possibly over your budget .
Finding anything for sale at the moment is an issue .
 
V1701 said:
Hmm, yes you'll get better advice from the mobo forum but here's my take - there are few boats that you could potentially use on canals as well as river/coastal. One that springs to mind is Viking (26/23), more often than not outboard powered, friend of mine had one in our coastal marina, I did some work on it for him which revealed to me how flimsily/badly built they are. Inland waterways are speed restricted so if you envisage that's where you'll do most of your boating I'd look for something with a couple or one diesel modestly sized (couple of 30/40hp engines, say, in a 30 footer) engine(s) on shafts rather than outdrives, mainly for easier maintenance. With such a boat you'd be able to do some coastal cruising, at modest speeds (say 5-10 knots) in relatively calm conditions and making allowances for wind/tides. You can coastal cruise in just about anything (and people do) in the right conditions, it's when you have to go against the tide, when there's wind over tide or the weather turns unexpectedly that you need sufficient power to get out of trouble. Boats that would fall into the above category however are few and far between, they'll mostly tend to have more powerful engine(s) than that. If you envisage mostly coastal use I'd look for more power, again if it were me I'd look for shaft drive rather than outdrive but that's just what I know & prefer. Try to get an idea of fuel consumption of anything you're considering, the figures for boats that travel at faster speeds (15/20/25 knots) through water can use an eyewatering amount of fuel...
Click to expand...
Thanks. Yes fuel consumption does seem pretty crazy!
 
MartynG said:
I suggest you look into which rivers you have in mind as there are not really very many in the UK. As for canals the restriction would be bridge clearances as well as depth of water and width of the locks. Few boats are happy on both rivers and canals.
I am sure 2 x 75hp is okay as long as you are happy to go slow.
A single engine would be more economical . Something like a Nimbus 27 Famillia with a single 130/150hp perhaps? Possibly over your budget .
Finding anything for sale at the moment is an issue .
Click to expand...
Thanks, I will check out the Nimbus 27
 
I'm new to boating so I'm doing a lot of research and asking a lot of questions.

I'm looking for a boat of around 30 feet (more or less) that is capable of some coastal cruising, also some rivers and possibly canals, I realise this will be dependant on bridge clearances and draught. My budget is 20 to £25,000.
My question is - What would be the minimum recommended engine size? I'm looking for a diesel engine due to fuel availability, and consumption.

I've looked at a couple of Fairline Mirage 29's, which I liked. The one I liked, had twin 75hp diesels and the broker thought that might be too small for coastal cruising/sea use?

I'd be very interested to hear peoples opinions/advice on what they think the minimum size engine I should look to buy in a 30 foot GRP hulled cabin cruiser. Also any recommendations of a boat type/make? Thanks in advance
 
If it helps, I have a 30ft steel boat based on the non tidal Thames powered by a single Volvo 60hp on a shaft.

It is ideally suited to the river where there is a 5mph speed restriction and very often you can’t go that fast due to other vessels - rowers with very little freeboard who can easily be swamped, or when passing moored craft.

My fuel consumption is 2 LPH

In my opinion a twin engined boat is a waste on the non tidal river, there is no advantage but all the disadvantages - two lots of servicing, double tuel consumption etc,etc.

mine has a draft of 0.9m and an air draft of 4.3m and I can’t get down any canals.

if I take mine tidal, it’s cruising speed is 6kts, punching tides is not normally worth considering. If I go coastal it is with the tide all the way.

if you want something for rivers and canals then, as already suggested, Vikings are ideal, but built down to a price and are all (I think) on outboards which will mean petrol with all the problems that brings, generally walking to garages with fuel cans etc.

Bearing in mind the time it takes to go boating generally, I’d suggest having a careful think about where you want to spend most of your time and buying the vessel most suited to that.
 
where will you be based? Are you thinking planning or displacement hull?? You also have to think about the age of the engine(s) and hours run as well as the HP...... over time some horses may have escaped and you would not want to thrash older small engines against tides.
 
Another thought: if you intend to do much weekending with a deadline for return to work on Monday (bosses tend nto to see bad weather as an excuse for not turning up ona Monday!) If s you need sufficient power to push you through a patch of unexpected bad weather, as well as foul tides etc. In Chi for example, if you miss the tide getting to the Bar inbound, you may have to buck a 4 - 5 knot current, and if there is any strength behind an offshore wind you need ample HP to push you through! My boat could easily achieve hull speed in still water at half throttle (24 ft 12hp x6kts), but pushing home againsta solent chop and foul tide, needed everything it could give to get home for deadlines.
 
Mark26 said:
In my opinion a twin engined boat is a waste on the non tidal river, there is no advantage but all the disadvantages - two lots of servicing, double tuel consumption etc,etc.
Click to expand...
You are mostly correct but I wouldn't say ''no advantage''.
Having had a single engined boat I would say handling in marias, entering locks etc is much easier with twin engines .
However I would not rule out a single engined boat if it had sufficient power or if I had no desire to go on salty water .
 
I'm pretty confident in saying what you are looking for is not suitable for the canals. You can take the risk ..
 
Schmoo said:
What would be the minimum recommended engine size? I'm looking for a diesel engine due to fuel availability, and consumption.

I've looked at a couple of Fairline Mirage 29's, which I liked. The one I liked, had twin 75hp diesels and the broker thought that might be too small for coastal cruising/sea use?
Click to expand...

In purely practical terms 30' yachts regularly cruise under engine alone when there is little or no wind or if they need extra speed to get home.

A 30'yacht can do 6 or 7 knots with a 12 to 20hp diesel. As a motor boat (as you don't have sails as an alternative engine) it's best to have twin engines which could be a main inboard and an outboard. Many yachts motor across the channel so it's not engine size that makes a boat seaworthy or not it's the construction and design. A single engined Aquastar 27 is a good seaworthy boat if well maintained and there are nice examples well under 20k
Aquastar 27, Newcastle upon tyne - Ad 117848

The broker is clearly in a hurry if he thinks you need 75Hp you might want more power or speed but you don't need it for coastal or offshore journeys.
 
You must log in or register to reply here.

Share this page

Top