Forget anything that small, the smallest pumps and injectors are for 1.5hp to
2hp engines, and that 48W load could almost be run by a small model engine.
In IC terms, petrol are probably the most available, there may well be tiny
diesels around but if you want anything with a bit of life and spares
availability then a larger engine would be better.
Look on ebay at the 'mini-motors' that are being sold, they came off the little
kids scooters etc.
Peter & Rita Forbes
I'd steer clear of little two stroke engines. They are fine when
they're being thrashed, as in a chain saw, or a kiddy bike, but won't
take kindly to pottering along. They'll tend to oil up. It's perhaps
a bit big, but a 4 stroke lawnmower engine will be very reliable, and
is likely to come with a speed governor, so will automatically cope
with change of load on your generator. Also cheap to find and easy to
An ex lawn mower engine is a good idea.
Beware of the lousy efficiency of most small generators though. I built
one some years back driving a car alternator. I very carefully worked
out the electrical power then added some. The combination was all
connected and started. Great I though. Then I connected a load and the
motor stalled dead. Not the gradual slowing down but a sudden bump and
she stopped. I now have to run the alternator at well below it's rated
output to make sure it works. Even now, a flat battery makes it
Of course Kim, if you make a set like this, you can show it at steam
fairs and get in for free :-)
Wot? He said waking with a start. Was that aimed at me? Ducks just in
I've a Petter AA1 attached to a 24 volt alternator - came from a nice chap
on this 'ere list - two flat 12volts do make it grunt a bit & it's no
lightweight, after all. The exhaust note is impressive & it's not a device
one would want to run after ten in the evening.
If searching for a power unit, use a Honda OHC four stroke motorcycle based
unit, now licence built in China. Not expensive, powerful, reliable &
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