Cold startup with the new system.
6 Likes
Very sweet Chris. thanks for the video.
So the new valves are just to shut off the woodgas for gasoline driving?
Yes. In normal operation they stay open all the time.
Super nice job Chris! I noticed that your AF gauge was in the green (rich) after start up. Mine runs best on the lean side. Is this adjustable in any way? Yours seems to run very good this way but does it lean out once it warms up? I have to do a little more studying on how that diaphragm knows where to set the butterfly first shot in the box. Is there an initial linkage adjustment that puts it at about 50/50 instead of 60/40 or whatever?
At 9:50 you can see when I put it in gear, the reading goes lean and stays put. I’m not sure what causes that. Could be the initial “pushed” gas was a bit richer than normal.
At any rate, it’s never gone overly rich, just enough the meter shows it. Anytime under load it stays right on target, occasionally it will go a tad rich when you romp the throttle. I’ll have to make (yet another) video showing the AFR as I drive around town.
Nope, that’s the thing… there’s no initial adjustment because the full range of travel is under the control of the diapghram. No matter where you set it, it will rebalance itself.
1 Like
Don, if you go back to post 132 where max has the diagram, you see the separate bellows for cranking mix. the next couple posts explain it’s operation.
Since the main diaphragm is only controlling the pressure of the gas and air to be equal, any adjustment of the actual fuel air ratio would have to be done with the dual throttle plates if I am understanding this correctly.
HI Chris saenz,Can the 60 40 adjustment be changed a little one way or the other,with longer hoses on one side,or the other,Glad you got it working,looks like nice add on.THANKS
Hi Kevin,
Nope, the pressure balance has to be 50/50, that’s the only way it can work… The membrane will constantly move until it finds that equilibrium.
Changing the hose lengths won’t really matter; adding a valve in the air sensing line will dampen the responsiveness of the valve to prevent overshooting. But eventually it will still find that 50/50 equilibrium.
Now, what you could do is add an additional manual valve on the air line between the diaphragm and the throttle. This would let you restrict the air further and richen the final mixture some more. This will compensate for weak gas, or unsymmetrical air/gas lines.
1 Like
Thanks,sounds like it should work good like it is.
I keep thinking that the gas valve is always wide open like it was before the auto mixer and that the membrane only adjusted the air valve like I have to do manually now. That is where I was wrong. the membrane adjusts both gas and air! It took a while but I think I finally got it. 
Close… The membrane itself only controls the air. However we are throttling both gas and air. This is why at crank up we get a tiny measured equal amount of each - not from the diaphragm but from the throttle itself. As we move to wide open throttle, the gas plumbing becomes the restriction and the air flap is auto-adjusted to match.
I feel like the more I explain it the more complicated it gets… Sorry guys.
WOW that is really amazing, and hard to wrap my head around! Great demo, great job, Chris.
Made a trip around town tonight, and kept the camera fixed on the AFR gauge. The idea here is showing how the automixer responds to throttling up and down, long pulls, sudden stops, and idling. I did some of all of it in the video - even managed to stall it once, goofing around. But if you drive sensibly, it’s remarkably stable. Even a bit boring… 
5 Likes
Fascinating!
How does the Lambda meter behave on gasoline on the very same route, equally driven?
Max
Normally on gasoline the meter will swing back and forth, back and forth from rich to lean. On heavy acceleration it will swing to the rich side briefly, then return to its normal pattern.
Looking good Chris .
Thanks for posting .
BBB
Very nice, I want one. I’ve been experimenting with fuel size some more in kiln dried, air dried, and fresh cut fuel. I’m seeing a lot of variation in A/F ratio as I drive. This would come in handy. Yes, it was boring. 
2 Likes
Added some check valves to the system, and redid the blower setup. This makes startup a breeze.
Front gas vent:
New underhood plumbing (check valves are red):
New blower setup:
8 Likes
Hi, Chris!
It seems to me, that this new vent out route is also sucking from the hay filter, as there seems to be no backflap. If this is so, then fresh air from the motors secondary air intake through the balancing flap (at the membrane) and through the partly open twinflaps can flow backward through the gasline to the hay filter.
In the hay filter, there can be resident GAS!
If they mix and go into a sparking commutator in the shop vac ???
No more questions necessary…
Hope the electric motor has separate ventilation for cooling!
Max
Yes, that’s possible. However the air leakage from there should be very slight, and hopefully not enough to cause a problem. The path of least resistance is directly through the gasifier.
I’ll keep testing it out and let you know what happens! 