Smallest diesel?

For "work" engines, I know Jonsereds made diesel chainsaws back in the '50s-

GTO(John)

Aha. Thanks. I see there's some online info on that saw, and it's a definite candidate.

Ed Huntress

--FWIW there's an outfit called, IIRC, Davis Diesel Developments that sells retrofit kits for model airplane engines. The smallest one I've seen fits onto a Cox .020.

The BSA Cub BSVC3 is 2.5HP at 1050RPM (made in India) The Mitsubishi L2E 2 cyl is a 635cc unit rated at 7HP at 1800 RPM.

May be some smaller.

See:

These do not however run on conventional diesel fuel. I don't know what the smallest one running 'ordinary' diesel is.

Probably not the smallest, but I have a Yanmar diesel generator that is only

Thanks, all. Those are a bit smaller than I expected. I guessed that something around 600 cc was the lower limit.

Ed Huntress

They use diesel plus some sort of additive. And they use a carb and glow plug, not timed injection and compression ignition.

Dan

Developments

Sorry Dan, they don't use a glow plug, they ARE compression ignition but do use a carb. They are fuelled with paraffin (kerosene), oil and ether mix; the ether permits compression ignition at a lower CR than a 'real' Diesel engine. Martin.

I don't know how big of a diesel you are after, but this is a 4 hp one on ebay. Time is getting near the of the auction. But he seems to have one for auction every week.

Thanks, Richard. I was just doing some checking to answer a question that came up today. The brand is interesting. I don't recognize it, but I haven't looked into small engines lately.

Ed Huntress

IIRC, it's Chinese a knockoff of a Yanmar.

-Carl

Try Yanmar (famous for single cylinder sailboat power) or Lombardini (builds a way cool itsy-bitsy 4 cylinder turbodiesel that's popular on portable sawmills). Mitsubishi used to build a 17 hp two cylinder that Toro used on the

-Carl

Aha. Thanks, Carl. Do you know if it's made under license from Yanmar?

Ed Huntress

Rightly famous too - those things run and run and run...

My Yanmar anecdote:

For about 16 years I crewed on a 28' racing sailboat. The winter before I started the owners had removed their 7HP single cylinder Yanmar and replaced it with an air cooled gas engine because the gas engine was lighter. (80 lbs vs. 300) They more or less abandoned the Yanmar on the loading dock in the unheated truckwell where they stored the boat.

The new engine was a piece of crap that constantly overheated, and the weight savings made little or no difference in sailing speed. So the next winter they decided to re-install the Yanmar. I was there to help. We were looking at the engine (still sitting on a couple 4x4s in the truckwell). One of the owners was explaining things to me - "if the battery dies, you can pull that compression release there and crank here to start it".

I said "like this?" and gave it a crank. We were both shocked when it started and ran! No electrical, fuel, or cooling water connections - it was running on old fuel trapped in the filter bowl. It had been at least 15 months since the last time it ran. I don't know how long it would have run on the trapped fuel - we shut it down quick since it was puffing black diesel smoke into the room (and had no cooling water).

That engine ran the boat for the next 16 or so years. It eventually needed some work - the owners _never_ changed the oil. Never used fuel stabilizer either. We raced twice a week all summer, probably an hour of run time each race (half hour before, half hour after). We often were able to go nearly all season on one 12 gallon tank of fuel. Whatever was left in the fall is what we started with in the spring.

We managed to start it backwards once - didn't crank it hard enough to get over top dead center, but it ignited the fuel anyway and away she went - exhaust coming out the air intake. I guess we were lucky it didn't suck enough water from the muffler to hydro-lock it.

Nice engine...

John Kasunich

Back in the early '60s my former editor at American Machinist, Andy Ashburn, started his series of trips to Japan to see what was happening there. One place he stopped on an early trip was Yanmar, which no one in the US had heard of. He was very impressed, and said that the company, which was just a little operation then, was one to watch. He said that someday they'd make some of the best diesels in the world.

Ed Huntress

Don't know, but I doubt it.

-Carl

Probably not the smallest, but small and old, Sachs D500, design by Holder gmbh, licenced to Sachs

Kai St-Louis