A new Chinese recoil starter for the venerable Yanmar L40.
I found it in a dump, at the Balad air force base in Iraq. I Q-tipped each component perfectly clean, packed it in a box and mailed it home (just like Radar O’Reilly on MAS*H).
Its been running ever since, charging batteries.
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The economy of four-stroke engines with a working volume of less than 100 cc is questionable, I think that the two-stroke engine has the advantage here in all respects. My brother is a postman and for many years he delivered the mail on Tomos mopeds, the last generations of these two-stroke 50cc engines had very little consumption and good power, finally they got Italian four-stroke engines, which consumed much more fuel and had many more maintenance problems , now they have electric vehicles.
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I agree Tone. Small 4-strokes cannot replace the useability of small 2-strokes.
After a strong 10 years of using my powerful FS250 Stihl brush-cutter machine it finally became real noisy with rod and piston death-rattle.
So I rented a Makita brand of four-stroke brush cutter to try before replacement purchasing.
Heavier. Slower engine RPM. Much, much slower to cut back overgrown grasses, weeds and light brush.
I am old. I can now work only in daily 2-4 hour bursts. That machine was too damn slow to be clearing daily 300 feet of drainage ditches and fence line sections.
So the “square body” FS250 40.2cc was no longer available. Stihl replaced with the more compact “just as powerful” they say; 37.7cc MS240. Certainly, better than anything four-stroke or portable electric. But not as work-done, capable as the older larger MS250.
I wish I had waited to order-in the 2-stroke ECHO SRM-410U larger engined 42.7cc Japanese machine instead.
S.U.
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I agree with you both, 2-strokes have their place as small light-weight, powerful engines.
Only drawback’s should be “woodgassing” them, lot of trouble, 2stroke’s very sensitive against resistance on intake side, and lot’s of poisonous gas with exhaust (no way i can find a translation for “spolningsförluster”? Flushing losses??)
I attach a pic of a “pulsator” system for 2-strokes, i find interesting.
Drawback is, a new cylinder head is needed, for the inlet valve. These was made for bigger, slow running engines, but calculation of the volumes and such should make it possible to use for smaller engines, those check-valves at the top could be changed to reedvalves.
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you know you are defeating the anti-theft device 
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Is that one of those big Cadillac alternators you were talking about?
How long do you get on one tank of fuel with that yanmar? It looks about the same size as my 10hp yanmar clone.
I can’t figure out what’s going on with that engine in the picture at all.
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Tom, lm glad lm not the only one 
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If I’m trying to explain… the bottom left is sucking in air (or a bad mixture of air and gasoline with oil) during underpressure conditions, as well as some gases from the gasifier on the right, well, these gases do not reach the engine crankcase, but only fill the chamber and part of the pipe above. The piston moves down, overpressure is created, the valve opens at the top and the overpressure pushes part of the gases into the cylinder, and some of the mixture of air and gasoline below. The throttle is designed to enrich the mixture.
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Spot on 
Tone, as you said, right side pumps woodgas, which don’t reach the crankcase, the “pulsator pipe” should be dimensioned for this, bottom right valve is controlled by a speed-governor.
Valve on left side controls air, enriches the mixture, controlled by operator.
This engine in picture uses pressure lubrication, but i don’t see a problem to introduce oil by the air?
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Was out, walking the dog right now 10.00pm (is that right? 22.00?)
and saw this colorful spectacle at the sky:
“Aurora Borealis” the Northern Lights, can seldom be seen in my part of Sweden, especially not when in a village, where streetlights and all disturbs.
Sorry for the bad pic, hard to photo with phone, but thought it was worth sharing anyway
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We very seldom see the Aurora Borealis in central Washington state, but when we do see it, it is awsome indeed to view in the Northern sky.
Bob
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Just for a time reference it’s 4 pm here in Nebraska (mid continent USA) March 23. What day is it there?
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23 of March here too, it’s a good idea with time references, i’ve always have a hard time counting for time-zones 
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I have a small world globe collection I use for perspectives. I preferer the ones more geographical then political. So Goren you are 10, 15-degree longitude segments after-spin lagging from me. ~10 hours. So you are clock face advanced from me 9-10-11 hours. Or from your perspective I time lag behind you. Ha! Always late. Waiting to occur.
I am in the 46 degrees north latitude. You are in 60 degrees +/- 10.
Major Oceans currents, and major air rivers effects are more relevant to both of us than just geographical degrees numbers.
I still look for globes with these marked onto them.
Globes can show better seasonal tilt sun angles with a focused flash light than numerical graphs. Seems more real. A globe showing we are like-it-or-not, modern-world, in it together.
And globes unlike flat 2-D maps are not choices of skewing of true geographical areas. True separation distances then too.
No maths. Childrens two legged dividers.
Regards
Steve unruh (I’ll hold the bloomed out daffodils picture until the upcoming two days of green grass covering snow.)
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“Spring snow” came early today at 5pm/15:00
Sorry. Bad camera angle trying to keep the lens not wet spotted.
S.U.
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Ha, Steve, we too are at 46*. Yet our climate is rather different.
When l went to the US it felt great. At Norths place, l woke up fully rested at 4 or 5 in the morning, and explored the nearby nature. Later the jetlag slowly vanished and l started waking up at more “normal” hours.
Ha! But when l got back home! The jetlag kicked in the other direction. I was like an sedated owl for a week
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Some better pic’s of the Northern Lights, wife snapped it with real camera.
Over my neighbours house.
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Looks just like Bill’s pictures in Minnesota. It’s a small world afterall. We see them here as well but since we normally have cloud cover and they only pop up occasionally it’s a crap shoot to experience them.
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