General Witterings -
New Year on Rosy

We've had a quiet, but extremely pleasant, Christmas and New Year on Rosy, mainly in the company of Mike and June who are the next-door-neighbours on their narrow boat 'Temujin'.

The weather has been variable - we've had sunny days, rainy days and snowy days, and we've been iced in for two or three days.

Mike and June have been boating for well over 30 years - they had Temujin's hull built 30 years ago, and had owned several boats before that.  Their European adventures have been on going for at least ten years.  I feel somewhat inadequate in their company, as not only do they possess all sorts of practical skills that I lack - mainly engineering skills such as welding - but they are disciplined enough to get on with what needs to be done, even though that means working outside in cold, wet and windy conditions.  However, with Mike's advice, guidance and practical help, several of the outstanding jobs on Rosy have been sorted out.

Rosy now has a fully-functioning fuel system.  The simple solution was to feed the excess 'spill-way' fuel straight back into the fuel line that connects the header tank to the engine fuel pump.

With Mike's help, I now know what most of the fuses do, and, as he is the sort of person who has a torque wrench in his tool-box, he 'torqued-down' the cylinder head bolts on the new Perkins engine (as required by the 'First Service' schedule).

Work on the exhaust system has been ongoing.  One of the runs that was a touch too long has been shortened, and a substantial bracket has been welded up, as a support for the vertical silencer

I have finally quietened down the 'Epping' solid fuel range in the back cabin.  Even when it was burning on tick-over, it gave out so much heat that sleeping in the back cabin was uncomfortable.  The solution was to put a fire brick into the back of the fire box, reducing the volume of the fire box by 30 or 40%.  This gives a small saving in fuel (though not, surprisingly, a 30 to 40% saving) but, more importantly, the fire is easier to keep in, and it gives out less heat.

That all sounds like a lot of work, but in fact they have not been particularly time-consuming.  The day-to-day business of shopping, cooking and exercising Fanny the Wooflet takes a touch more time, but I seem to spend hours watching TV - I haven't read a decent book for a couple of months.

I had a welcome visitor just after Christmas - Benny, who I met in Ghent a couple of years ago.  We had a trip out to see the WW1 battlefield at Verdun.  I hadn't realised that the Verdun defences were so extensive.  We visited two sites, one 12 km westish of Verdun, the other 20 km westish of Verdun.  One had been a village on a hill - now there are, literally, no stones or bricks standing on top of each other.  What was the main street is totally unrecognisable - it has some massive mine craters, pock marked by shell craters.

Engine Cooling

The magazine "Canal and Riverboat" has run an investigation into engine cooling on narrow boats.

Over here in France, a high proportion of narrow-boaters report engine cooling problems.  I had assumed that this was because the wider and deeper waterways here in France encourage us to run our engines a bit faster than in UK.  Plus, of course, the higher ambient temperatures in summer exacerbate the problem.  However, the letters in "Canal and Riverboat" suggest that insufficient cooling is a design fault in many narrow boats.

The only guidelines that I have seen suggest that 1sq ft of skin tank needs to be in contact with the canal water for every 3.5 of engine hp.  However, this figure seems to be taken as a guide, and in practice, the square footage is reduced because (so it is argued) the full hp of the engine is very rarely used.

Furthermore, not all skin tanks follow best practice, which, for a skin tank on the side of the boat:

• the top of the side tank should be below the water-line;
• the hot water inlet to the tank should be as far as possible from the colder water outlet.  Usual practice is for the hot water to come in at one end of the top of the side tank and for the cooled water to exit out at the bottom of the other end of the tank;
• internal, horizontal baffles should be fitted;
• a valve should be fitted at the highest point of the skin tank to enable trapped air to be bled off.

It should be noted that:

• the thickness of the tank is not particularly important;
• it is necessary to ensure the cleanliness of the surface of the tank that is in contact with the canal water.  That is to say, weed should be scrubbed off the outside of the skin tank at regular intervals.

A skin tank built up on the base plate is considered to be less efficient (because the hotter water flowing through it will tend to rise to the top of the tank (giving you a nice warm floor), while it will be the cooler water that will be in contact with bottom, cooling surface).

If you are cursed with an over-heating engine, there are several solutions.  The classical solutions are:

ONE.  Fit a second tank, with the output from the bottom of the first tank leading into the top of the second tank.

TWO.  Somewhere between the hot water exiting the engine, and the not-cool-enough water entering the engine, arrange for it to be routed through a steel pipe that is welded to hull of the boat, below the water-line.

I have heard of two 'oddball' solutions:

ONE.  Run the output from the skin tank through a car heater unit (rescued from a scrap yard?).  When the engine starts to get too hot, the heater unit is switched on, and its fan blows air over the water tubes of the heater, cooling the water in them.

TWO.  Insert an oil cooler into the pipe that exits the skin tank and enters the engine.  The oil cooler itself consists of a stack of small-bore tubes contained within a larger tube, this larger tube acting as a water jacket.  The hot coolant will flow through the tube stack, to be cooled by raw water flowing through the water jacket.

This raw water will have to be pumped from the canal, using, perhaps, a Jabsco type electric water pump.  Switching this pump on will bring the additional cooling into service.

This system can be fitted to a boat relatively easily, using 'over the side' plastic pipes to bring the water in and out of the boat.  Incoming water should initially pass through a filter to 'sieve' the water before it enters the tube stack.  It makes sense to try to locate this filter in the boat but above the waterline.

If using a 'through hull' fitting, a sea cock should be fitted immediately in-board.  The fitting should be fitted far enough below the water line to avoid sucking in detritus from the surface.  Some skin fittings come with a grill on the outer surface to prevent the ingress of large leaves, plastic bags etc.  Such fittings should be avoided, as clearing an external blockage could create considerable difficulties.  Better to have the inlet as an open tube, and to have arrangements such that the tube from the skin fitting to the filter can be rodded through.

Toodle pip!!

Bill