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Ford 390 Autolite carburetter Starts ok but only runs on full choke the two fuel needles don’t seem to make a difference. ( they used to be ok before cleaning).

This carburettor did work ok, but I decided to clean it, float levels are good, I’ve checked for vacuum leaks, around the engine, nothing done on actual motor other than removing and replacing the carb had been done, The only thing I noticed was that when I pressed the accelerator pump handle one ONE Venturi squirted fuel, I’m not sure if both should? So no leaks, no fuel pin changes when engine running and the choke had to be full on I’ve also noticed that has the engine gets warm the choke doesn’t alter ?? Help Neil be

Pᴀᴜʟsᴛᴇʀ2
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Neil Willis
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1 Answers1

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The Venturi cluster on that should be able to be removed with the air horn off of the carb body. There is also a gasket under there and a series of very tiny orifices going up the center of the brass tubes (internal venturi).

Be sure all of those holes and passages are not clogged. I suggest using a wire plucked out of a wire brush to clean out any debris. There is also a brass tube down the center that should be hollow as well, make sure that the tiny tube will allow the flow of air or carb cleaner through it.

While disassembled, make sure there's a check ball in the bottom of the accelerator pump well, which normally has a spring holding the ball in place. There also should be a check ball under the center screw that was holding that Venturi cluster down. Both check balls are necessary in order for the accelerator pump to work properly.

Good luck to you!

izzy
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Doug Nelson
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