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Some Q-jet help?

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Old 02-20-2005, 10:21 PM
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swifty71
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Default Some Q-jet help?

This is nuts! I can't get my Q-jet to stop running so rich. Fuel is actually spilling down the primary venturis and pooling on the throttle plates while in idle. Idle adjust screws have no effect and yet it's not flooding/spilling over around the airhorn gasket? I've been through the carb twice, replacing all gaskets, ensuring correct needle-hook placement and float adjustment. From spark plugs to tail pipe is sootey black! Not to mention impossible to time/tune. This is for a 71 350 used on both cast iron and Eldelbrock intake manifolds now. I like Q-jets when tuned properly, but I don't know how to fix this one. Any thoughts?

Swifty-
Old 02-21-2005, 01:17 AM
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BigBlockk
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Start the engine and start advancing the distributer slowly. As the idle comes up reset it at the carb. If you have a light set it to about 16 degrees before top dead center. This should get it to run ok so you can tune some more.

Make sure the idle air and main venturi bleeds are not plugged. A paper clip works here. Hopefully you now have some control with the idle mixture screws. Three turns out from lightly seated is a good place to start. You did remember to put the main jets and rod back in didn't you?

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Later.....
Old 02-21-2005, 08:08 AM
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swifty71
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Thanks for the advise. Jets and needles checked good and were re-installed. I'll get a paperclip and check the venturi bleeds for blockage too.

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Old 02-21-2005, 09:28 AM
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Surfer69
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If gas is pooling while idling make sure and check main throttle position screw. You may have the throttle open too much at idle exposing t-slot which may cause that. Also check thottle linkage and blade position and make sure the primary blades open straight up and down with full throttle. My .02

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