Relocating Battery Charger

[RaymondR]

A couple of years ago I built the illustrated engine driven battery charger and located it on deck just forward of the mast on the coach roof of my IP40. It proving to be a bit of a nuisance and now having about 1,000 watts of panels on the solar farm I decided I no longer needed it and removed it. Of course nature being what it is we have suffered weeks of overcast weather in my usual summer anchorage and consequently I have decided I need it back. But since I don't want the inconvenience back, where to put it.

My model of Island Packet has a quaint little helmsman's seat which, it having also proved lnconvenient, I have made alternate seating arrangements and the location appearing handy to the transom, which I could penetrate with an exhaust to keep fumes and noise out of the boat. Out came the seat and the engine was set on a couple of fuel containers to see whether it would fit between the rudder post and the back end of the cockpit.

[RaymondR]

After removal of the air cleaner, exhaust and fuel tanks it appeared that by making a recess in the back of the cockpit it would fit. So out came the jig saw and a hole appeared.

A fair bit of pondering on how I was going to tidy the hole occurred until I realised I had a steam table tray left over from my fridge rebuild. So in she went.

The next problem was how to mount the generator in place.

After another long ponder I realised I could do a "Full Custom Garage" like Ian and recycle the IP seat to both house the charger and again play a useful purpose on the boat. Back she came and the jig saw came out again.

So, this is where we're at and doing some heavy pondering on how I'm going to fill the blank section in.

[RaymondR]

I fitted a plywood insert into the upper and lower sections and have boxed in the expanded halves with 1/8" ply and will now fibre glass between the two plywood inserts.

[RaymondR]

Back in the days when I was a steel boat owner I very seldom gave serious consideration to fire mitigation, I would keep a fire watch and extinguisher when welding or cutting and be careful with flamable fluids but that was pretty well the extent of my precautions. However, on the other side of the coin below-waterline hull integrrity was a fairly constant concern. Now being a fibreglass boat owner other than penetration soundness I am hardly ever concerned about hull integrity but fairly constantly concerned about fire prevention and mitigation. Consequently I am spending a fair bit of time pondering upon the housing of a gas fired engine which will be operated within a largely fibreglass part of the hull and deck. Oh for just one instance of a perfect world.

As much as possible I am designing metal flame barriers between the engine/alternator unit and the fibreglass hull parts and will be using a four hour foam product to fill cavities wherever possible and I am considering water injection into the exhaust system for both ignition source mitigation and exhaust sound reduction.A further precaution is the housing of volatile liquid fuel outside the hull and cockpit and consequently the fuel tank for the unit will be mounted on the upper transom outside the hull with a vapour sealed cap and low level tank vent.

Whilst considering changing the fuel supply to the carburetor, originally an unprotected hose fairly hard up against the air cooling fins of the cylinder, to a metal tube I had a thought that it would be better to move all liquid fuel bearing components outside and away from the engine and electrical components where any leakage would be less likely to come into contact with hot engine or electricalaly generated ignition sources. Consequently one of the strategies I am now pondering on is moving the carburetor aft of the transom and positioning it below the fuel tank for gravity feed.

Moving the carburetor Off the engine block and aft would require a flanged manifold onto the block, departure via a 45 degree elbow, about a three inch run to claer around the head then a 90 degree turn and a straight 8 inch run back through the transom with the carburetor mounted on another flange. This arrangement would include 135 degrees of flow disruption and about 13 inches of increased flow friction into the fuel/air supply to the engine but this is not uncommon in multi cylinder engines.

Suggestions, critiques, criticisms and even a light application of negative curmudgenry are welcome.

[nuku34]

Excuse me for asking what might look like a stupid question, but...
Why do you need a separate petrol engine driven battery charger when you already have, I assume, a diesel propulsion engine in the boat which could easily drive a fairly large alternator?

[RaymondR]

Originally Posted by nuku34

Excuse me for asking what might look like a stupid question, but...
Why do you need a separate petrol engine driven battery charger when you already have, I assume, a diesel propulsion engine in the boat which could easily drive a fairly large alternator?

The main reason is that I like to have an alternative available should the cranking and house batteries become too low to crank the main engine which has happened to me a number of times in years past. There are a number of secondary reasons including I already have all the equipment from a previous boat and the quaint little helmsman's seat was a waste of space and I just like to stay entertained with boat projects.

There is an extant thread with a fairly detailed discussion on having charging options titled:

Why you might consider still keeping your generator (Multi-page thread 1 2 3 4 5 6 7 8)
Chotu

[RaymondR]

One of the reasons the original box on the forward coach roof was so large was that I wanted to be able to run a belt drive alternator on one side of the motor and also belt drive a high pressure plunger water pump on the other for an RO unit.

With the reduction in sizes required to house the engine under the helmsman's seat this is no longer possible and whilst pondering on the subject I revisited an idea to use a belt driven auto power steering pump to hydraulically transfer power to various functions such as an alternator or RO pump.

Anyone out there tried anything like this?

[Bowdrie]

Originally Posted by RaymondR

I revisited an idea to use a belt driven auto power steering pump to hydraulically transfer power to various functions such as an alternator or RO pump.

I've worked on a few boats in the 40>50' range that used hydraulics for the windlass,(one also used hydraulic power for a 120V AC generator,) but they were power boats with a lot more room and access than the typical sailboat.
And one 43' sailboat that used hydraulics for propulsion, (a nightmare).
Trying to snake high pressure hoses/return hoses around to various devices together with the reserve tank/filters/coolers/manifolds/valves sounds like an easily doomed project on a smaller sailboat.
It will only take one fitting or hose to fail and the ensuing disaster will make you want to sell the boat.
Should you end-up with a bilge full of hydraulic oil and the bilge pump activates you'll have a whole new problem should someone see and report it.
We'll leave the noise created and the maintenance issues for another thread.
But, an automotive pump that only has to operate a single device can be successful, (an electric clutch, not a full-time operation like in a vehicle).

[RaymondR]

The steam table trays are getting a fairly vigorous workout on this project.

The first image illustrates one pan used to form an alcove in the back of the cockpit bulkhead and a second utilised to form a drip pan under the engine.

The second illustrates the base for the engine and alternator installed in the drip pan. I will probably use nitrile rubber sheeting under the engine base for vibration isolation.

My intention is to entirely surround the engine/alternator unit with SS sheeting and fill any volumes between the SS sheeting and fibre glass structure with 4 hour rated foam. Hopefully this will make the installation more fire resistant and assist with noise reduction.

[RaymondR]

Originally Posted by Bowdrie

I've worked on a few boats in the 40>50' range that used hydraulics for the windlass,(one also used hydraulic power for a 120V AC generator,) but they were power boats with a lot more room and access than the typical sailboat.
And one 43' sailboat that used hydraulics for propulsion, (a nightmare).
Trying to snake high pressure hoses/return hoses around to various devices together with the reserve tank/filters/coolers/manifolds/valves sounds like an easily doomed project on a smaller sailboat.
It will only take one fitting or hose to fail and the ensuing disaster will make you want to sell the boat.
Should you end-up with a bilge full of hydraulic oil and the bilge pump activates you'll have a whole new problem should someone see and report it.
We'll leave the noise created and the maintenance issues for another thread.
But, an automotive pump that only has to operate a single device can be successful, (an electric clutch, not a full-time operation like in a vehicle).

I almost screwed up by buying a mains voltage aircon for about $4,000 and installing it in the place the previous owner of the boat had removed one from. Fortunately I came to my senses and cancelled the order.

The problem with going this route is that I would either have to start inhabiting marinas to connect to the mains power system or run a 240 volt genset on deck or install a bigger inverter and supply it via a bus alternator on the engine driven battery charger.

Whilst pondering on the alternatives I returned to a scheme I had considered when the charger was in the box on the for-deck of belt driving an auto aircon in addition to the alternator on the battery charger.

The helmsmans seat on the IP40 is T shaped and the upright is roomy enough to allow installation of an auto aircon under the engine, there is plenty of room in the keel to install an un-folded, tube in tube heat exchanger and the evaporator and it's fan would fit into the location from which the old aircon was removed.

I have the bits for the larger aluminium fuel tank being tacked together for a trial fit on the transom and am fabricating the pieces for the new water cooled exhaust manifold to take to a second shop and will drive the twenty odd miles to the catering supply store for more steam trays with which to extend the SS lining downwards to include the electric clutch and pulley for the auto aircon compressor which I'm thinking Sanden model SD5HO9 or 11 or 14 because apparently they can be driven counter clockwise.

[RaymondR]

Whilst pondering on pulley arrangements for the aircon drive I realised that if I implement the aircon it will most probably get far more use than the battery charger and that since I have not used the battery charger for about eighteen months, needing to swap the drive V belts between the alternator and the aircon compressor would not be an onerous requirement and that consequently a concurrent drive is not required.

Also, it is about fifteen feet from the transom to the back of the water tank where I could route the condensed refrigerant to the filter/drier and the evaporator and that a linear tube in tube in tube condenser heat exchanger could be implemented. The anulus between the second and third tubes would be utilised as the return line to the compressor.

[Tin Tin]

There is only so much power that can be taken off your little diesel, read the installation specs.

[RaymondR]

Originally Posted by Tin Tin

There is only so much power that can be taken off your little diesel, read the installation specs.

It's a gasoline engine, 5.5 hp hence the new transom mounted fuel tank, all metal fuel lines and stainless steel and 4 hour rated foam engine enclosure.

Unlike the synchronous motors in hermetically sealed AC aircon compressors the belt driven compressors used in auto aircons can be run anywhere between about 700 up to to 6,000 rpm and the power draw is related to the speed and output pressure the compressor is driven at. Matching the compressor to the motor is merely a matter of V belt pulley sizing.

I considered using one of the 24 volt DC electric compressors that are used in long haul trucks to aircon the sleeper cab when the main engine is not running but it would require a much bigger alternator. If the belt driven one works out and I switch to lithium house batteries in the future I will consider doing the alternator upgrade and DC electric compressor.

[RaymondR]

The fuel tank in place on the transom.

Fabricated from 3" x 3" x 1/8" SHS. Two lengths of the tube had a 2" section cut out of one side, making them into C sections, and were welded together and 1/8" end plates, with flanges to allow fastening to the coaming, were welded on. The spigots sticking up towards the ends are for the helmsman's backrest.

[RaymondR]

The water cooled engine exhaust is fabricated from aluminium tube.

The small spigot towards the bottom of the vertical square tube is the cooling water inlet and the outlet is partially hidden under the top square tube toward it's end image right. There is also an inlet to inject water into the vertical tube.

The round tube towards image bottom is the section which passes through the transom and overboard.

There are about six vertical, partial baffles angled at 45 degrees inside the 40 mm x 40 mm inner tube which form a convoluted path for the exhaust gas. Don't know if that will silence it much but it will probably be as effective as the Honda original.