Raw water engine & electricity questions

[chubby]

Hello everyone

 

I've been looking to buy a narrowboat to live aboard for around 6-8 months , mostly researching and viewing to get ideas for what might suit me and my budget of around £25 000. I now have the cash available to buy with a view to moving on to it properly in around March next year so if I buy in the near future I can get work done on it so it's all ready by this time .

I'm looking at two or three possibilities and each has a question mark over them so ...

 

One is a 1984 cruiser with a raw water cooled BMC1.5 engine . My understanding is that this needs to be drained over the winter to prevent damage from freezing so is it suitable for live aboard purposes ? Or in reality does it require only to be drained during the very height of winter for several weeks , maybe 2 months . Or is it fine for living on ?

 

Another boat could be perfect as it ticks every box perfectly but only has 12v electrics . Is it a straightforward job to fit all that's needed to use a shore power point ?

 

Sorry if these seem like dumb questions to the more experienced out there but it's my first boat and now that I've got the cash to buy one after saving up I don't want to get it wrong !! If they're suitable then I can view and possibly look to get surveys organised .

 

Any help or comments are very welcome and thanks for your time and opinions

 

Cheers

[Monkey 1]

I live aboard my 1980s narrowboat with a raw cooled bmc engine & 12v electrics. It will be my first winter but I hope not to drain the raw side of the system. I have installed a remote temperature gauge inside the engine bay so I can monitor the temperature & run the engine should it get to the point it might freeze the pipes. I have noticed it is always a few degrees above outside temperature anyway so will see how it goes. I'll also keep a pot of water under there so I can see instantly if it begins to freeze. If it gets really cold for a long period I'll just run the raw side dry for a few seconds before shutting the engine down. People have said to wrap the engine in an old duvet when it's not running to keep the temperature inside too.

 

As for electrics, everything on my boat is 12v. I have a 12v fridge, all LED lighting, a 12v TV. I have a 300w inverter for charging my phone, laptop, toothbrush, radio, shaver etc, & a generator to power the washing machine, although this is not up to the job so willl be getting a better generator soon.

[chubby]

Hi Monkey 1

 

Cheers for your reply - very encouraging . I'm looking to move my boat to a yard with shoreline electricity hook up so would ideally like to use it or at least know it's available to use on my boat .

The boat that's just 12 volt has a suitable fridge , so that's sorted . Am I right to think that I would need to fit , as in your boat , an inverter for charging laptops , phones etc and just make sure I don't overload it ? I'd like to hook up some solar panels too if the price isn't too drastic .

 

I like your ideas about the engine - the remote thermometer , the duvet and the pot of water . One of the boats has this older type of cooling system but would appear to have been looked after . I'm considering a pram cover for the cruiser stern which might also help .

 

Thanks for your replies as they make me believe that both boats are potential lives boards and neither issue prevents thier suitability .

Cheers

[Monkey 1]

I'd say a pram hood would make quite a difference to the engine room temperature yes. I have a deck cover on my cruiser stern & that definitely keeps it a bit warmer. The engine bay soon warms up when you run the engine & it stays warm for a long time.

 

A basic inverter is very easy to fit. My 300w was on offer from Maplins at £30. I have connected it strait to the leisure batteries with an in line fuse. I can have my laptop, phone, radio & toothbrush charging at once & it manages very well only running its cooling fan occasionally.

 

I've not had anything to do with shore power so can't help there sorry!

 

Just to add, when I first queried using a raw cooled boat through winter one member suggested keeping a light bulb on inside the engine room, the heat generated would keep the area frost free. If you do use shore power this would be very easy to do.

[bottle]

The only item that can not be powered from 12v is the toothbrush and that could be changed to a manual version.

 

Is it a straightforward job to fit all that's needed to use a shore power point ?

 

Yes.(if you know what you are doing)

Edited November 29, 2012 by bottle

[Monkey 1]

I'm sure with a bit of ingenuity even the toothbrush could be converted!

 

I cruise a lot & charge everything as I go so an inverter works for me. I rarely use the inverter to run things, just to charge.

[Black Ibis]

Avoid raw water cooling! Ours was raw water cooled but we had to get it replaced with a skin tank because it was forever blocking!

[matty40s]

Avoid raw water cooling! Ours was raw water cooled but we had to get it replaced with a skin tank because it was forever blocking!

 

I moved a raw water cooled boat from the centre of Birmingham to Northamptonshire a couplke of weeks ago during the maximum leaf fall time. It never blocked once. The only issue I had was the prop getting a bundle of leaves round it, which affect virtually every boat at this time of year.

[Monkey 1]

My raw cooling has never blocked. It has two strainers filtering the water that rarely have to be cleaned out. The raw cooling system makes perfect sense to me!

[MtB]

My raw cooling has never blocked. It has two strainers filtering the water that rarely have to be cleaned out. The raw cooling system makes perfect sense to me!

 

Nor mine. The raw water is drawn into a large vertical 'mud box' through a grid of holes drilled through the hull, and then into the water pump.

 

I've yet to experience a blockage but I suspect if I did, it would be leaves covering the grid of holes on the outside. Easily removed with a broom.

 

MtB

[koukouvagia]

Avoid raw water cooling! Ours was raw water cooled but we had to get it replaced with a skin tank because it was forever blocking!

 

This is another of those questions that sharply divides boaters' opinions. I like raw water cooling and have a direct version on the Kelvin and an indirect system on the BMC 1.8. I never have to worry about whether a skin tank is up to the job when running hard on a river. The BMC system has a mud box which I clean out periodically.

 

I have to admit there is a design flaw on the BMC set up. Unfortunately the raw water outlet lines up with the engine hole of any boat sharing the lock with me. I have to make sure I always go to the right hand side of a double lock.

 

 

 

 

 

 

[Black Ibis]

Raw water cooling can be good if the system is well designed. Ours wasn't. It had a small intake tube which often sucked itself flat and a small "mudbox". The filters on the outside and baffle plates were also ineffective. So, if the OP decidesto go with a RW cooled boat they need to check how good a system it is!

 

Also, our skin tank was designed for rivers so no worrying about overheating!

Edited November 30, 2012 by Black Ibis

[kevinl]

Avoid raw water cooling! Ours was raw water cooled but we had to get it replaced with a skin tank because it was forever blocking!

Where do you cruise? I'm raw water cooled and never have a problem. Do you mainly river or one of the few clear but weedier canals. I've hired about the cut a bit and never really had a problem anywhere is it locational thing you've suffered from.

To the OP what about air cooled, simplest of all the cooling types.

[Tony Brooks]

Where do you cruise? I'm raw water cooled and never have a problem. Do you mainly river or one of the few clear but weedier canals. I've hired about the cut a bit and never really had a problem anywhere is it locational thing you've suffered from.

To the OP what about air cooled, simplest of all the cooling types.

 

 

Just remember that automotive based engines are designed to run with pressurised cooling systems that are not easy to provide for direct raw water cooled units. In canal use this will not be a problem but once you starts to demand higher powers and speeds the water may/will start to boil in certain areas inside the engine although any temperature gauge will still show normal. You are very unlikely to get any symptoms on a direct cooled engine until the build up of scale/salt on those hot-spots causes the metal to overheat locally and crack.

 

 

Edited to add:- This was not intended to frighten the OP, if you have direct raw water cooling then you have to live with it, but on a BMC 1.5 I would make sure the thermostat was removed for river work. The intention was to put some balance against those posters who seemed to be extolling the virtues of direct raw water cooling (as opposed to raw water + heat exchanger cooling, which is totally different.

Personally I would never run anything but a proper marine unit, designed form the ground up as direct cooled , as direct cooled. My choice would be keel/skin tank cooled.

Edited December 5, 2012 by Tony Brooks

[FadeToScarlet]

Where do you cruise? I'm raw water cooled and never have a problem. Do you mainly river or one of the few clear but weedier canals. I've hired about the cut a bit and never really had a problem anywhere is it locational thing you've suffered from.

To the OP what about air cooled, simplest of all the cooling types.

 

When Black Ibis and I first bought the boat, it clogged up on the BCN, the north Oxford, the GU, and many times on the local river Ouze. We each had to go swimming a couple of times to clear debris that couldn't be flushed out, normally supermarket carrier bags.

 

There was no proper mudbox, only a 20mm or so inlet with a baffle plate. A single leaf would block it.

[Monkey 1]

I've not seen any mention of direct raw cooling? My bmc is raw cooled with a heat exchanger so is a pressurized system. It copes well with a bit of hard work & never seems to get any hotter on the gauge as a result. I'd imagine removing the thermostat would just stop it warming up as quickly, not good.

 

It also has a huge mud box with a removable strainer that is easily checked from the rear deck. I can see how potential problems might occur without a decent mud box.

Edited December 5, 2012 by Monkey 1

[Tony Brooks]

I've not seen any mention of direct raw cooling? My bmc is raw cooled with a heat exchanger so is a pressurized system. It copes well with a bit of hard work & never seems to get any hotter on the gauge as a result. I'd imagine removing the thermostat would just stop it warming up as quickly, not good.

 

It also has a huge mud box with a removable strainer that is easily checked from the rear deck. I can see how potential problems might occur without a decent mud box.

 

 

See the OPs first post - "Direct raw water cooled".

 

One of the problems is that people seem to refuse to be specific about this sort of thing. If you say raw water cooled then no one knows what you are really talking about.

 

Your engine should not get hot as long as the heat exchanger is adequate for its job and does not get blocked as they often do and as long as it is a pressurised system you should not get any localised boiling, however hard you work it. But that is because it is heat exchanger cooled and not direct raw water.

[Monkey 1]

See the OPs first post - "Direct raw water cooled".

 

 

 

Nope, still can't see it!

 

I was unaware that any narrowboats had such system? Is it common?

[GUMPY]

Nope, still can't see it!

 

I was unaware that any narrowboats had such system? Is it common?

My narrowbeam cruiser has.

Got a petrol engine as well (ford crossflow)

And a webber carb a real go faster lump

[Tony Brooks]

Nope, still can't see it!

 

I was unaware that any narrowboats had such system? Is it common?

 

 

Sorry, you are quite right - me reading what I thoughtw as there (three times)

 

However saying that he had been advised to drain the engine implies that it is direct cooled, otherwise he would only have to drain or treat the raw water part of the system and I am sure that you know an easier way of dealing with that than draining.

 

Nope, still can't see it!

 

I was unaware that any narrowboats had such system? Is it common?

 

 

Probably not common but when we get onto older boats there must be sufficient around to make assuming any referred to as raw water cooled are all heat exchanger cooled unsafe. They are more likley to crop up on GRP boats, budget ones and self fitouts. There are many vintage engines and proper marine engines on the system that do use direct raw water cooling but tend to be so lowly stressed or are designed for it so there is no problem. Its the converted automotive ones that may suffer.

[Monkey 1]

Overnight the temperature in my engine compartment dropped to +2, I'm not sure of the outside temp but the canal was half inch thick with ice this morning. It's good to see it is maintaining a reasonable temp so far. It's bloody cold out today, even the dog won't venture out!

 

OP, have you decided on a boat yet?

 

Tony, am I right in thinking some bmc units were supplied new as marine engines? I think someone once told me that.

[Tony Brooks]

Overnight the temperature in my engine compartment dropped to +2, I'm not sure of the outside temp but the canal was half inch thick with ice this morning. It's good to see it is maintaining a reasonable temp so far. It's bloody cold out today, even the dog won't venture out!

 

OP, have you decided on a boat yet?

 

Tony, am I right in thinking some bmc units were supplied new as marine engines? I think someone once told me that.

 

 

By the time the 1.5 was in production BMC had an approved or official mariniser who was Newage and later Tempest. However the popularity of the engines were such that many others started to marinise new units. Meakes of Marlow for one and I think Thorneycroft/AMC were started early as well. I do not know about the Broads but got the feeling that the Perkins 4-10x series of engines were more popular there. Eventually the ready availability of marinising parts allowed all and sundry to marinise them - not always with the best of results.

 

They were available with all three forms of cooling: direct raw water, heat exchanger or keel cooling and I have seem both direct and heat exchanger systems connected to skin tanks.

[Monkey 1]

Thanks Tony, an interesting read. Like you say, I imagine there are all sorts of hash ups out there where folk have chucked together their own version of a marinised bmc. When I think back, I took a bit of a risk having not even heard my engine until the day I collected the boat!

[nebulae]

I have always understood that the main advantage of raw water cooling is that you can have a water cooled exhaust.This applies to direct and indirect systems.You can then use rubber exhaust hose.The water acts as a silencer as well as a coolant.Obviously,a lot of trad engines use a solid lagged exhaust as well as raw water cooling,but it is very convenient for modern lightweight jap engines,as the standard pump only has to circulate through a heat exchanger.The secondary pump can be rated to the size of the heat exchanger.A filter such as the Vetus unit(fitted above the water line)will help the longevity of the impeller.I have a raw water system which works O.K.Fitted it because the previous engine was air cooled so I had no skin tank.All things being equal,I think I would go for skin tank cooling.Having said that,we had no problem for our autumn cruise with heavy leaf fall.

[bizzard]

Years ago when most folk didn't have as much money as they do now got up to all manner of DIY mechanicing.

Very common ''mainly with petrol engines'' was to use ALL automotive gear from vehicle breakers yards.

Any inline engine and gearbox being used but mainly Ford, BMC and Rootes group.

The cars radiator would often be used along with the hoses ect, ducting cool air into the front with its original fan and ducting the hot air away outboard, both through homemade plywood or similar trunking. The gearboxes could be converted to give a more or less similar ratio for fore and aft gear. The cars propshaft perhaps shortened would be used. A proper separate thrust plumber block had be used though as car gearboxes don't have output shaft bearings designed to take fore and aft thrust. The cars rubber mountings would also be used. Ideally a hydraulically operated clutch would be used with either a homemade lever system connected to the gearlever to withdraw the clutch plates or the cars original clutch pedal would be used. Even most of the cars electrics ''gauges and all' could be used too. The cars fuel tank was often used too. And they worked pretty successfully.

I reckon you've all got it too easy these days.