Gas Engine Driven Battery Charger

[onestepcsy37]

ten years ago i bought a honda 1000 and a 40 amp smart charger - total cost less than a thousand dollars. takes up little space and starts first time everytime. run the honda in the cockpit or on deck so no fumes.
ten years on they are both running and - NO RUST!

[Cadence]

I'm sorry! It appears something like trying to reinvent the wheel.

[RaymondR]

Originally Posted by billknny

Are you sure that thing will be able to cool itself in that insulated box?

Those little engines throw out an enormous amount of waste heat, and are designed to operate in free air. Throw in a couple big alternators working hard, and I see a serious "thermal problem", up to the point of being dangerous.

The engine takes in it's cooling air through the pull cord housing and I will install an inspection hatch in the cover at this point. I am also looking for a 12V li near actuator to lift the lid when the ignition switch is switched on. If that is insufficient I will install a flap in the side of the box.

Pondering on it for a moment I might install the flap anyway. The airflow will then be in via the flap on the bottom of the box side and out via the raised lid.

Thanks for raising that issue, it's going to result in a considerable improvement.

[RaymondR]

Originally Posted by onestepcsy37

ten years ago i bought a honda 1000 and a 40 amp smart charger - total cost less than a thousand dollars. takes up little space and starts first time everytime. run the honda in the cockpit or on deck so no fumes.
ten years on they are both running and - NO RUST!

Been there, done that one.

On my previous boat I had a 2.2 kW genset in a box on the deck. I also had a large transformer with four high ampage diode bridges to rectify the AC to dirty DC. The dirty, unregulated DC was connected into the DC bus bars from the solar array allowing it's regulation by 3 X 20 amp solar regulators. The 2.2 kW genset also powered my lathe and mill and the microwave.

I was in the process of changing to an engine driven battery charger and inverter when I sold the boat. The engine also had an air compressor attached which I used for hull maintenance on the steel boat. I retained the engine when I sold the other boat hence it's availability for the extant project.

I suspect the Yamaha is suffering from water ingestion to the electrics. I had it on the for deck with a cover over it however being in a tidal river I suspect rain may have blown under the cover as the boat changed heading with the tide change whilst I was taking a nap. A more permanent arrangement was required, preferably without 240 V AC coming out of it.

Since the boat I have now came with a 2,500 Watt inverter I decided on going the battery charger route.

[RaymondR]

Originally Posted by Cadence

I'm sorry! It appears something like trying to reinvent the wheel.

I'm 75 years old and grew up in a country town which still had two blacksmith works in operation. One of them had a wheelrite tank and re=rimmed wagon wheels. Many of the sheep stations still kept wagons and horse teams which were used in the roadless, rough country. Drovers also still used horse drawn wagons.

There were still a lot of wooden spoked auto wheels in use and I remember my father soaking the wheels of his Esex in a round zinc bath tub when they dried out too and the spokes loosened.

Post war as the country got richer everyone started to replace their old bangers with hew cars with pressed steel wheels.

Then one day I saw a car with nice shiny, machined alloy wheels and now pretty well everything on wheels comes with them.

I've seen the wheel re-invented four times in my life time.

According to the manufacturer, the 200 amp hours of LiPo batteries I have fitted can accept a charge rate of 100 amps. I should be able to manage 200 amp hours in a couple of hours with the engine driven charger where it would take 5 hours with a 40 amp charger run ftom AC.

[StoneCrab]

I enjoy seeing makers at work.
Keep at it, you'll get it figured out.

I am am left wondering how much horsepower an alternator consumes. Does this motor have any trouble turning over two at full output?

[CORALSEA TRAMP]

Been there and done that-You have a ton of power and the limiting factor is the charge rate your batteries will accept-they are self limiting--Also it is mandatory to change the cooling fans on your alternators (opposite rotation)
They will definitely overheat even with a reasonable load!! Report back in ten years.

[GILow]

Sorry to sound like somebody’s Mum here... but take care with these things. Every couple of years somebody inadvertently kills themselves with carbon monoxide because they put the petrol powered generator in the wrong place on the boat, or the wind changed, or a hatch was left open.

If you must use these things (and in this age of cheap solar I really don’t know why you must) check your CO detector is working first.

[CORALSEA TRAMP]

Apologies--Batteries are not lead acid and therefore NOT self limiting--Brain out of gear-(been a long night)

[Rotten Ricky]

This is an interesting thread to me, as I am in the process of assembling a gasoline engine with a Delco Remy CS-144 alternator. These alts are rugged and cheap to buy and repair and were used on fire trucks, ambulances and high-end cars in North America from about 1995 to 2010. They are a favourite for after-market companies who re-wind them with stronger rectifiers etc to produce up to 300 amps. When de-rated for continuous use, the standard model is still able to pump out 100 amps, even though my new 7 Hp engine will not likely be able to sustain it. A couple of points:



Any small engine will not be able to direct drive and still be able to get an automobile alternator to work efficiently at such a slow speed. A typical alt on a car spins at close to 7,000 to 9,000 RPM even though the engine will run at about 2500 RPM. And this is for the light load in a car and not the load on it that deep-cycle batteries usually need for recharge. Therefore a small motor needs a pulley/double-pulley that is about 3 times the diameter of the alt pulley for the speed of the alt to not only produce power for charging, but to STAY COOL ENOUGH!

Many alts are killed by not being cooled enough cos they are not spinning hard enough to draw enough air through the alt to cool them. Heat is the worst enemy of an alternator! Running an alt at slow speed is a very unwise idea. Thankfully the CS-144 has larger air-flow cavities for better cooling, though this makes it about 1/2" larger in both diameter and length than the more common Delco Remy alts like the 12 SI. But that is why it runs cooler and longer. Incidentally, they usually have the same 2"-long mounting foot, etc, that the smaller Delco alts use.

The CS-144 uses a common, reliable and inexpensive regulator but one can use a manual over-ride (with constant monitoring or sensors built in to prevent over-charging) or a smart charger system. Relying on the proposed simple motor-generator set-up with a standard regulator will likely leave your battery banks under-charged and with a vastly reduced life, and the motor generator in this case will run much longer to do the same job. I think some knowledge is missing about how to charge batteries properly.

There is no way the proposed motor gen can be run in a box without over-heating unless it has powerful fans driving cooling air through it. Far better to have it outta the box.

In spite of some sour reports, the Chinese-made small engines I have used on my pressure washers have been excellent, starting immediately and running long and strong. Also, above about 80 amps it is wise to use a double pulley with double belts, or better still, a grooved serpentine type belt.

Cheers, RR.

[Lepke]

Nicely built box, but what's the alloy of the aluminum box? I wonder how it will hold up to salt. And the engine will over heat with no more venting than the box has.

[billknny]

Running that thing on deck is a great way to make sure you have an anchorage all to yourself.

Not the way to win friends!

[RaymondR]

Hi GILow, well aware of the CO problem.

About 15 yeara ago I was taking a nap when I heard a lot of activity on the dock. Being a curious soul I stuck my head out a hatch and found it was a 50' fero being secured by the RCB sea rescue folk. It had been allowed to go aground at high tide and not laid over as the tide fell, the subsequent toppling had knocked a hole in it.

When I wandered up to get a closer look I found that there were four little gas powered pumps in the saloon roaring away to keep it afloat and people wandering in and out to have a look.

I tied a rope back and forth across the companionway and advised the owners partner to sit beside the hatchway outside and not allow anyone to go below whilst I went to rig some other flex drive, gas powered, submersible pumps. About ten minutes later I noticed she had gone and was on the jetty gossiping and someone had removed the rope. Looking down through one of the deck hatches I was lowering a pump through I observed a person looking back at me from the cabin with the CO atmosphere.

I'm aware of these problems from my oil drilling days but there's a lot of ignorance out there.

Hi Rotten Ricky.

Aware of the cooling problems mate and will be observing closely and remedying any as they appear. Normal part of the development process.

Hi Lepke.

I use a lot of alloy in my projects and have not had any problems so far with corrosion.

Hi Billknny.

I like to have anchorages to myself and already have about 600 Watts of solar with another 300 going onto the dodger roof which is my next project. The problem is that with one or two overcast days alternate forms of battery charging are required. In these circumstances just about everyone else in the anchorage will be running generators for battery charging. At least mine will only have to run a couple of hours a day.

[Chuck Hawley]

I'd be very interested in whether someone has taken the little Honda 25CC or 35CC four-stroke engines and used them as a DC charger. They seem like such neat engines, and there must be an alternator out there which would mate up to them nicely. Perhaps one of the 55A Hitachis which are on Yanmar inboards? With current sensing you could regulate the output to match the power available from the engine so it wouldn't stall or operate inefficiently.

Seems like it would be a good 10th grade science project.

Chuck

[RaymondR]

Originally Posted by Chuck Hawley

I'd be very interested in whether someone has taken the little Honda 25CC or 35CC four-stroke engines and used them as a DC charger. They seem like such neat engines, and there must be an alternator out there which would mate up to them nicely. Perhaps one of the 55A Hitachis which are on Yanmar inboards? With current sensing you could regulate the output to match the power available from the engine so it wouldn't stall or operate inefficiently.

Seems like it would be a good 10th grade science project.

Chuck

They used to be available in Australia, popular with the 4WD folks. Only had a 35 amp alternator though. Still available with 55 amp now.