Cody's '76 Sierra

Reconnected my kickdown “passing gear” wire on the transmission and I see why it was disconnected. I’m stuck in 1st!

I bet the switch at the pedal is bad or needs to be reset. Only drove the truck 3 miles but if I don’t get into 2nd gear at 20mph after fiddling with the switch I’ll just disconnect

Update: IT DOESN’T HAVE THE SWITCH

No wonder I’m stuck in first, it’s getting a live 12 volts!

Edit: on the bright side at least the solenoid in the transmission works, just need to wire in a new switch.

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I think my nickname should be Flip-flop or Flimflam because I keep changing my mind.

I took the old junky Quadrajet apart to at least replace the seals, but I also am thinking of taking the plunge and going for the Mother Earth News 4bbl woodgas carb. I’m enchanted by the idea of being able to punch the accelerator or have a gasoline idle to help the woodgas along while not having compromised stoichiometry.

I’m glad I at least took the carb apart, this thing is disgusting internally.

Also the float is disintegrated.


Hopefully I can cram this into my paint can of carburetor cleaner dip.

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The PCV circuit in the base plate was completely stuffed with carbon, I bet that’s why this engine has oil weeping at some of the seals. I might go with a catch can system so the positive pressure just evacuates the entire time.

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Well it’s done, for better or for worse.

Edit: the 1.5" Stainless that I have for the cooling rail tree fits almost perfectly in the hole. I ordered a smooth 90 degree pipe for this.

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Hurrah!
Using the best of the 20th Century MENS system, brought forwards into the 21st Century WK.

CodyT. I feel you will be setting up for a driver that smoothness, and transition-wise will be a non-electronic standard tough to beat.
Regards
Steve Unruh

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I’m sure it was a rollercoaster watching me hem and haw at different ideas. What finally convinced me was where MEN says they powered not a 350cui, they powered a 454cui Big Block!

If I ever have to do this again I will be buying a Chinese knockoff QJet, which are much much cheaper than buying even a core must be rebuilt Rochester.

Here’s a link for anyone that hasn’t seen the guide, first half shows for a 2bbl Ford Pinto Motorcraft licensed Weber style carburetor. Other half is for a 4mv pre-1973 style Rochester Quadrajet. My electric choke model is a different type and it did make drilling the hole more difficult.

This is a dual throttle style conversion that lets you run a gasoline idle or use the gasoline as a passing gear.

This is not to be confused with their other carburetor conversion which was much more complicated but only used one pedal with a woodgas primary and gasoline secondary.

Edit 2: here’s a link to the older style carburetor that uses an Autolite 5200

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Now we play the waiting game for my new float, rebuild kit, and gas tank repair putty to seal up the jets and tubes I removed from the carb. Should be here tomorrow God willing.

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Can you explain what you are doing, I don’t understand?

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With this Quadrajet 4 barrel carburetor I have separated the linkages to have two throttles and two chokes.

The first link I sent in the comment above it shows how Mother Earth News did this conversion.

Rochester Quadrajets have much larger secondaries than the primaries as a means to have good fuel economy with power in reserve.

I’ve blocked the gasoline jets in the Secondaries and drilled a hole to add a pipe for woodgas. The choke flap will be used for air mixture.

With this arrangement I can leave the gasoline system running and run woodgas without affecting the stoichiometry of either system. If I am on the highway I can even use the gasoline pedal to gain momentary power without needing to adjust my air mixture for woodgas. Also handy to have an idle of gasoline for heavy slow traffic.

I used a 1.5" hole saw to cut the hole in the back and I’ll be using epoxy to add a pipe for woodgas. Mother Earth News used this setup for a 7.4L Chevy V8 to great effect so it should work just as well for my 5.7L.

The conversion isn’t entirely finished in my case, I’m waiting for my epoxy and some other components to arrive.

Here’s some steps I haven’t completed yet:
079-138-i14(1)
079-138-i15
dual-carburator-03-15000-miles-550p-jpg

One interesting note that MEN did for spark advance is instead of twisting the distributor cap, they instead hooked up a cable to the vacuum advance diaphragm and when it is pulled by the cable the timing is advanced.

dual-carburator-04-dashboard-550p-jpg
Motorcycle throttle for woodgas, the bicycle shifters is for woodgas air adjustment and timing advance.

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Great job Cody, interesting to follow and a lot of good information :+1:
That carb modification and the linkage that Chris S showed will give a very good and practical mechanical solution.

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Elbow came in, still need to fishmouth it.

Sprayed down all the carb parts with cleaner and I’m going to airgun everything to get any aluminum shavings out.

1.5" OD with a 2" Leg.

I’m going to tilt the elbow slightly downwards so moisture will run back down the gas piping.

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Here’s the ports I blocked with JB Weld Gas Tank Repair putty. Using this straw I double checked where the air is leading to.









Some of this is redundant because they lead into each other.

Some of these also had brass tubes and nozzles which I removed, they’re just pressed into place.

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Pipe is fish mouthed out, filed down, drilled and riveted in the top and bottom.

I don’t like the rivet job I did but it should at least hold it.

MEN says to silicone it down, so I used red RTV. Hopefully the silicone will keep it from wiggling.




If this gets leaky I might silver solder it.

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Nice work Cody, so with this setup on this carburetor you will only use 1 gas pedal to control everything? Gas in the primary and woodgas in the secondary on the carburetor. So you shut the fuel off and you go to woodgas. Turn fuel on and go back to gasoline. Or do both. Right?

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No it’ll be two throttles. Since I’ve gone back to a floor shifter I can use the old steering column shifter with a cable on the secondary butterflies.

Two chokes, two throttles.

This will be beneficial for when I’m in heavy traffic and just need an idle on gasoline or need a passing gear. It’ll be a split stoichiometry so it won’t fumble as bad and I can leave the woodgas adjustment alone. Woodgas will be like a tractor throttle so basically cruise control.

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I got too check this out later, I got a few old Chevy motors i could put wood too yet, and still have at least couple quaderjets.

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Kevin if you got the old 4mv manifold heat choke it’ll be perfect for it.

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Thanks CODY I save this trick for future project.I think I still have a quadjet intake left, v6 and v8 not sure,so it could be in buried storage .Under roof on side of my stock aid fence behind the shop.

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I’m gonna take apart my Weber 32/36 DGEV and see if I can do the double barrel conversion for my Mazda. If that’s the case, the Chinese clones of those DGEV are very cheap and you can get lots of conversion plates even for the old Jeep 4.0 carbureted inline 6. Mother Earth News used this conversion for their Chevy 6 cylinder generator using a Pinto carburetor.

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I’m taking a look at my DGEV which is the mirror opposite of the DFEV used in most Pintos.

They keep talking about not blocking the Power Valve vacuum.

Issue I’m seeing is the Power Valve enriches the mixture of gasoline but it dumps it down the secondary through a nozzle/tube right under the choke flap. It’s meant for full throttle. Note I’m not talking about the accelerator pump.

It bypasses the emulsion tubes entirely. Very odd.

I guess in the DFV versions the discharge tube is in the Primary

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