I started playing with an idea for my Lister 6-1 engine. I have some thick-wall aluminium tube of about exhaust size (no idea where it came from!), into which I cut an 10mm round groove using a form tool on the lathe. I wrapped some microbore copper pipe (the sort we use in the UK for central heating systems) into the groove. Filled it with water & fired up the engine. With a load on the engine, the water in the microbore pipe boiled in about 2-3 minutes IIRC. At the time, I didn't have any cladding over the pipe, so it was 50% exposed to air; nor did I have any thermal compound between the pipe and the aluminium tube to improve contact surface area; so I've no doubt the system could be hugely improved with very little extra effort.

I haven't gone any further with that experiment, but I've no doubt I could get a good supply of hot water from it; and it gets hot MUCH faster than the engine block. In fact, I'd be tempted to circulate the hot water through the block initially, until that gets up to temperature, before extracting the heat for personal use...

I'll take a couple of photos of the lash up later, if anyone's interested.

Ade, a lot of folks here don't have access to a lathe or machining skills

But, if you wanted water that was just "hot" in terms of, say, pre-heating a HWC or the like - then you're only playing with something like 55 degrees C.  And, if you kept the "cooling" water flowing so that there wasn't static water "sitting" and overheating - then the plumbing to heat water to that extent could be much much cruder - something that is the tech equivqalent of some i/2" copper pipe wound around some alloy tubing and slathered with high-temp silicone . . .

Excellent little setup there. The air-cooled Listers will last a very long time and the Marathon generator head is top-shelf for sure. Price seems very reasonable for a good running set like that.

It will be noisy and consume quite a bit of fuel whether or not any load is present. Load her up!

dieselgman

Hello everyone.  I'm new to the forum and have always been intrigued by the Lister Petter engines.  Found a guy selling one with a Marathon head on it.  Used to be a light tower and was converted to a generator.  Went and took a look at it and it seems to run pretty good.  Started up pretty quick in freezing weather.  Only listened to it run for a half hour or so and we hooked up a 220 welder to it to test it.  Didn't seem like it even felt the load at all.  Seems to be in pretty good shape.  I'd have to rework it if I bought it and put some casters on it to push it around my shop. 

Don't really know much about these  engines and generators.  He's asking $1500 for it but he's been trying to sell it for two weeks.  I'd like to use it for backup power for my workshop, power for camp and backup for my whole house generac, if it ever dies.  Anything I should look out for?  Are the Marathon heads considered good units?  He said he believed the light tower had 1600 hours on it when he dismantled it.  Thoughts?

Thank you.  It seems I may be missing a control box that would send / cut voltage to the solenoid at the appropriate times?
Thanks again!

Yes, I agree with Butch.