Electric choke/rich carb issues?

1984 CHEVROLET TRUCK
172,000 MILES • 7.4L • V8 • 2WD • AUTOMATIC
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TWEBB101
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I have a Quadrate 4 barrel (17080212-1024), mounted to a stock intake on an 84 C20 454. I recently replaced the hot-air choke with an electric choke, and since then, almost every time I start the truck, I get wet, black spatter shooting from the exhaust pipe, along with some fuel-smelling smoke. Once the engine warms (choke opens fully within 4-5 mins), the smoke clears and the truck runs great. With the hot-air choke, this problem didn't happen. Also, I recently replaced the spark plugs (they were all fouled, very carbon coated). I don't know if the fouling was just since the electric choke was put on, or if it's been running rich for the last 3 years (since engine and carb rebuild).

I re-adjusted the carb: choke position, choke plate gaps, pull offs, fast idle, etc. Also, I tried adjusting the air/fuel mixture screws, 3.5 turn out, set with vacuum, but that didn't seem to help much. The smoke is a lot less, but I'm still getting the wet spatter during startup idle. I've got some Berryman cleaner in the fuel tank to help clean up the carbon, but how long should it take? I just don't trust the engine right now...
Oct 14, 2024 at 4:15 PM
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STRAILER
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It sounds like the choke is too tight, I would back it off until you see a 1/4 inch of air gap when the engine is cold and when you open the throttle slightly, please upload pictures or videos in your response of any problems so we can see what to help you with.
Oct 15, 2024 at 10:07 AM
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TWEBB101
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Thanks Ken. Here are some pics/video of the current setup/situation.
Oct 15, 2024 at 10:25 AM
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STRAILER
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Thanks for the videos and images, it seems like it is running pretty good. Did you read just the choke before the videos?
Oct 16, 2024 at 9:46 AM
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TWEBB101
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No sir, that was before your recommended adjustment.
Oct 16, 2024 at 9:51 AM
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STRAILER
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Okay, it seems like it is running okay, did I miss something?
Oct 17, 2024 at 8:23 AM
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TWEBB101
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The smoke is a lot less, but I'm still getting the wet spatter during startup idle. I've got some Berryman cleaner in the fuel tank to help clean up the carbon, but how long should it take? I just don't trust the engine right now.
Oct 17, 2024 at 10:05 AM
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STRAILER
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That fuel treatment should take a few days, I would fine tune the choke to get it to run the way you want it too. How do the spark plugs look? If there are black I would back off the choke and instal a new set of plugs.
Oct 18, 2024 at 10:42 AM
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TWEBB101
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Yes, they are black fouled. I changed them 10/2/24, because they were fouled, and I checked them last week and they're fouled again. I adjusted the choke last night and it seems to be working a bit better...from what I can tell? haha I also adjusted the air mixture screws, set to vacuum, so those *should* be okay as well?
Oct 18, 2024 at 11:01 AM
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STRAILER
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Yep, wind the screws in until the vacuum drops and then back them out slightly. If the spark plugs are black again you should roll a new set in or clean them.
Oct 18, 2024 at 11:20 AM