Fitting outboard motor to Fjord 30

[jakethepeg]

I am very new to this, and probably my question will be proof of that! I have been offered a Fjord 30 moored in the southern end of the Canal du Midi. It has 2 engines, one working , the other seized, and is dirt cheap!!. I would only wish to use it on canals/inland waterways, and wondered if it would be feasible to build a transom board and mount an outboard motor of approx. 35hp, and if so what other mods would be needed, ie remove original props to reduce drag, fit  morse controls. I have built 2 wooden boats from scratch and recently renovated a Citroen DS21, so feel I have the skill set to do it, but not the experience to know if is a sensible move. Thanks in advance for your input

[Neil Smith]

Why not just use it on the good engine?

Neil

[W+T]

I would as you say remove the prop and rudder as not needed and hold it back a little. It would be easy to make an outboard bracket.  Either beef up the transom or make and bolt on a stand off type. 

 

[Naughty Cal]

Why not just fix the "bad" engine or replace it?

[cereal tiller]

10 minutes ago, Neil Smith said:

Why not just use it on the good engine?

Neil

Or convert to Single Engine? those Boats were Single or Twin,it would mean relocating Shaft and Rudder,not to hard to Convert

Edited March 17, 2017 by cereal tiller

[Alan de Enfield]

Are you looking to keep it on the French waterways, or, bring it over to use it on the UK canals ?

 

If the latter, you may find that the beam (10 foot) and draft (3 foot) are not particularly suitable for much of the 'system', and, depending on model, the air-draft (up to 12 foot) could be problematic.

You would also need to look at the 'toilet system' as many of them were built with sea-toilets - if using it on UK waters then you would need to fit a black-water tank, suitable toilet and pump-out system.

 

To be realistic I doubt you could easily convert a twin-engine to a 'single', you would have to move the engine to the 'centre-line' of the boat, make new engine bearers, move and adapt the 'drive system' (is it on legs or shafts ?) etc etc.

It would (probably) be cheaper, quicker and simpler to repair the faulty engine.

 

If you could explain what your boating intentions & budget are maybe folks could advise on suitable, cost effective alternatives.

 

If it is similar to this Fjord 30, then the UK canals are not the place for it :

 

Edited March 17, 2017 by Alan de Enfield

[Naughty Cal]

If it has a sea toilet fitting a holding tank too it is not a difficult job. That wouldn't be a worry.

Personally I would scrap the outboard idea and look into fixing the broken engine or replacing it. 

Twin engined boats can be run on one engine until you fix the other one. Although beware that often one engine charges the batteries while the other heats the hot water and runs the power steering so you will probably be without one or the other for a while.

Buying the boat dirt cheap and then getting the engine running will undoubtedly add value to the boat.

[Neil2]

A wise man once said never buy something you don't really need just because it's cheap.

There's nothing particularly special about the Fjord which is probably why the current owner doesn't consider it worth fixing.  But the only way it makes any sense is if you get the boat for nothing and get the twin engines sorted.  Jury rigging an outboard is just throwing good money after bad and you will have a very hard time finding another buyer if/when the time comes.  

 

[jakethepeg]

Thanks all of you for taking the time to reply. I do not wish to bring it to the UK, more to use as a holiday place in France as I am retiring shortly. I have been told that manoeuvring a twin engine boat on one engine is quite difficult, but I have no experience of that. WDYT? With twin engines the boat was designed with a max speed of 22knots and cruising speed of 12 knots, so being restricted to a speed of 5 knots on a canal would mean the engine/s would be working at well below optimum efficiency, with a concomitant fuel penalty. As Alan de Enfield said, converting to a single engine would not be feasible, and rebuilding the U/S engine would cost twice what I would be paying for the boat. I would only want to move it occasionally to have a change of view  I will be paying about Euros 2500 with the boat fully kitted out, crockery etc and about euros 750 for the Honda 4 stroke engine

[Alan de Enfield]

25 minutes ago, jakethepeg said:

I have been told that manoeuvring a twin engine boat on one engine is quite difficult

The manoeuvring part is the easy part, as with one engine It will be trying to turn anyway, just make all of your turns in the direction it wants to go.

It is more difficult to stay in a straight line and (in effect) you will be proceeding 'crabwise' down the canal fighting the turning motion of the single engine. We have twin-engines  it is almost impossible to keep at river speeds with both running, so do understand the comments you have been told.

 

 

I'd keep it on just the single engine, and just try it to see how it goes.

Save your 'outboard money' (maybe to pay for an occasional tow when you want to move, if you are unable to manage the single engine handling)

[Tony Brooks]

1 hour ago, jakethepeg said:

 With twin engines the boat was designed with a max speed of 22knots and cruising speed of 12 knots, so being restricted to a speed of 5 knots on a canal would mean the engine/s would be working at well below optimum efficiency, with a concomitant fuel penalty.

We have a friend who used to have a twin engine Princess of similar size and they had no problem running or control on one engine when inland.

You will find any fuel penalty is in reality very small. Any fuel consumption data you have for the engine is probably at full throttle on a dynamometer. In reality you will get between 1 and 2 litres an hour at canal speed - just like the rest of us.

 

 

[Alan de Enfield]

11 minutes ago, Tony Brooks said:

 In reality you will get between 1 and 2 litres an hour at canal speed - just like the rest of us.

 

 

If only that were true :

Diesel engines use approximately 1 gal  (4.4 litres) per hour per 20 HP developed :

Fuel consumed is proportional to the power developed

Power developed is approximately  proportional to the cube of the engine revs

Hence fuel consumed is proportional to the cube of the engine revs.

So for my engines :

WOT = 2600 RPM

WOT = 143 HP

Fuel Consumption = 0.195 Litres/HP/Hour ( so 4.2 litres per 20hp, or, very close to the 'rule of thumb of 4.4l/hr/20hp)

My 36 foot, twin engine, GRP cruiser, at 5 knots, uses a fraction over 5 litres per hour, per engine, so I am using 10 litres per hour, (at 8 knots I am using 13.8 litres x2).

 

However I do agree with you that all my NBs  (with relatively small engines) have used between 1.5 - 2.0 litres per hour on the canal.

[Neil Smith]

If you changed the gearbox rotation and prop (some gearboxes work in any direction) i wonder if it would counter the tendency to pull to one side on a single offset engine.

 Neil

[Alan de Enfield]

32 minutes ago, Neil Smith said:

If you changed the gearbox rotation and prop (some gearboxes work in any direction) i wonder if it would counter the tendency to pull to one side on a single offset engine.

 Neil

Good idea - it may.

However :

1) we do not yet know if it is on shafts or legs. There have been all sorts of weird engine / drives fitted on these from Fiat engines to Volvo Penta engines.

2) the cost would be prohibitive for the OP (more than the cost of the O/B)

 

Edit after further thoughts :

Many twin engine boats have 'contra-rotating'  props / gearbox so it MAY be possible to swap the non-working engine drive train to the 'working' side.

Edited March 18, 2017 by Alan de Enfield

[Murflynn]

let's be realistic.

OP has implied that he wants to buy the boat to use as a 'holiday place' and some use on canals and 'inland waterways', so the performance under power would seem to be the least of his worries as long as he doesn't intend to use it on fast flowing rivers where power and manouevrability would be critical.

The boat is effectively being sold at a scrap price, so any consideration of future retail value is irrelevant, so long as he doesn't spend a lot of money on the boat.

Fitting an outboard may be the solution, but OP should consider:

- is the stern design suitable to allow access to the outboard for tinkering and maintenance? How will the motor be observed to check cooling water circulation (the big outboard killer)? How will the outboard be tilted when not in use (if necessary)?

- a 35hp motor is quite a heavy item. How will the outboard be installed, and removed in the future? - think about having a davit on the transom. 

- is it feasible to run the steering and throttle cables to the helm position?

- does the boat rely on inboard engine for electrical generation? An outboard will never be suitable for power generation and cannot sensibly be run while stationary for this purpose.

 

 

[Tony Brooks]

12 hours ago, Alan de Enfield said:

If only that were true :

Diesel engines use approximately 1 gal  (4.4 litres) per hour per 20 HP developed :

Fuel consumed is proportional to the power developed

Power developed is approximately  proportional to the cube of the engine revs

Hence fuel consumed is proportional to the cube of the engine revs.

So for my engines :

WOT = 2600 RPM

WOT = 143 HP

Fuel Consumption = 0.195 Litres/HP/Hour ( so 4.2 litres per 20hp, or, very close to the 'rule of thumb of 4.4l/hr/20hp)

My 36 foot, twin engine, GRP cruiser, at 5 knots, uses a fraction over 5 litres per hour, per engine, so I am using 10 litres per hour, (at 8 knots I am using 13.8 litres x2).

 

However I do agree with you that all my NBs  (with relatively small engines) have used between 1.5 - 2.0 litres per hour on the canal.

 

Please do not try to confuse with "science". Now re-read my answer.

Please explain how WOT consumption figures relate to any boat at "canal speed" unless the engine is of such low power it actually runs flat out at full power at such low speeds.

I would agree that this boat MIGHT produce more wash at low speed than a narrowboat so demand a little more power.  I would also agree that its  displacement hull design speed will be lower than a narrowboat but as long as you do not try to exceed that speed (whatever it is) the engine will be nowhere near developing maximum power at THE TYPE OF SPEED I SPECIFIED IN MY ANSWER. I suspect the engine would probably be developing rather less than 20 HP.

 

 

[Murflynn]

if Alan really needs 40HP (2 x 20HP) to propel a 36ft GRP cruiser at 5 knots then I suggest he's probably towing a trawl net, or he needs to wipe his bottom to remove yards of kelp, or the boat is shaped like a Uniflote pontoon.

[jakethepeg]

Once again thanks for sharing your knowledge and experience with me. For the time being I will go ahead with the purchase and see how I get on with the single motor, and I will probably get a small generator to charge the batteries if necessary

[Neil Smith]

Do you know what engines are fitted and if on gearboxes or outdrive legs.

Neil

[Alan de Enfield]

27 minutes ago, Neil Smith said:

Do you know what engines are fitted and if on gearboxes or outdrive legs.

Neil

I have made the point number of times - no reply

[Murflynn]

common ploy.   -   ask what seems to be an intelligent question that interests several forum members.   get them all worked up.  disappear without trace.

just a wind-up?  spoof or troll?  who knows?

[jakethepeg]

14 hours ago, Murflynn said:

common ploy.   -   ask what seems to be an intelligent question that interests several forum members.   get them all worked up.  disappear without trace.

just a wind-up?  spoof or troll?  who knows?

Actually none of the above, just someone who appreciates the depth of knowledge and experience on this forum:) Fitted with 2 Mercruisers 4L3 petrol with z drives, one working the other seized , at present on hard standing so easier to work on.

[Murflynn]

nice of you to revisit, let's hope you find an appropriate solution.

[Alan de Enfield]

3 hours ago, jakethepeg said:

Fitted with 2 Mercruisers 4L3 petrol with z drives, one working the other seized

Not the best of engines for IW work.

I do not know - but it may be worth checking the availability of petrol in the area you wish t use the boat - the UK waterways petrol suppliers are obvious by their absence.

 

Is it the engine or the z-drive that is seized ?

[Tony Brooks]

Now we know they are petrol engines ignore my 1 to 2 litres an hour. If will be maybe up to twice as much  because of the lower compression ratio plus the throttling of the intake at canal speed will make it worse.

I did think that or your purpose you might have found a deal worth pursuing but far from sure now. You need to be right on top of fuel system maintenance, use bilge blowers and be very diligent re safety when refuelling or working on the fuel system of petrol inboard boats. Every year it seem as if at least one person dies or gets seriously injured with accidents related to petrol powered boats.