OT but someone here might know

I dunno, but your average car alternator puts out 60 A at 12 V (700W, 1 HP), at a reasonable idling speed. More than enough to power a drill.

If you need 230V a suitable 12V-130V converter is only about £65, eg

-- Peter Fairbrother

There used to be an Australian company selling a car alternator that let you weld direct from it.You could also pull about 220v for power tools.

Depending on what you want to run an AC compressor can be used to run most air tools in the back of beyond. Can be fitted to the engine and turned on with the std magnetic clutch when required.

Dave

Thanks for the replies so far. The important part of my requirement is the vehicle is unmodified and the drive is taken from a driven wheel. Bob

Won't you need some sort of control loop driving the throttle input by monitoring the generator output?

Chris

Only for the perfectionists. Universal motors are not worried by differing frequencies. I want it to turn a pump anyway. No electricity in the way.

Bob

Probably dearer than a portable generator?

Henry

Quite likely true but I want the mechanical parts to drive a pump and trying to take a short-cut rather than making it from scratch.

Bob

Dunno, but I saw one on "Blue Peter", years ago, - knackered old truck, jacked up as you describe, wheel fitted, but no tyre, flat belt, guess the rest. Somewhere in Africa.

Also on that program, a revisit to see what had happened to the Blue Peter lorries sent over a decade before. No local Halfords, so batteries completely knackered. Solution was a car wheel welded outboard onto the fan pulley with outrigger bearing, length of rope, a dozen natives, one good pull, big cloud of black smoke...

Regards,

David P.

You would probably have to use a car without ABS otherwise it will try to brake what it thinks is a spinning wheel, doubt it would do the diff a lot of good either

Jason

That'd be traction control, which can be turned off in decent cars.

Mark Rand RTFM

Good point. Some cars won't appreciate the continuous use of the differential as the diff gears don't have sufficient lubrication to cope with continuous use, they aren't designed for it . Low speed, low load, you might get away with it, but from some experience this can be a major failure in the making. The diff may not fail at that use but what may later happen is the diff cross pin comes out as the locking pin fails due to fretting from partial seizure of the planet gear to cross pin.

My application is for tickover speed, for a few 10s of minutes. Vehicles are likely to be citroen 2CV or similar. ABS pah!!

Bob

ABS does not apply brakes, it releases them. Perhaps you mean traction control?

Cliff Coggin.

I've a feeling such things are used for starting hot-rods or racing bikes or possibly karts. I'm sure I've seen something of the ilk at a racing track, but I have to confess I really can't remember where or when. Thinking about it they would probably be rather heavy for yor application, but maybe worth a snoop about.

Richard