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Old 04-15-2021, 11:47 AM
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Location: Chapel Hill, NC
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Have you used a Unisyn to check the draw on both carbs? You can't get these carbs right without proper synching. The front carb cover is different from the rear, so swapping them front to back would mean taking them somewhat apart. It sounds like there is no fuel going into the front carb - no accelerator pump squirts and no firing in the front 3 cylinders. It is common on these carbs for the needle to stick, or for the fuel not to make it there because of a clogged path. Remove the cover of the front carb after you've had it running to see if there is adequate fuel in the bowl. It's a five minute job and will tell you a lot. Check the obvious things first before going for the exotic.

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Old 04-16-2021, 08:44 AM
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Post Before You Take It Apart.....

I prefer to use a flammable aerosol product to find intake manifold leaks but you can also remove the air cleaner and cup our hands around the air horn, s l o w l y close your hands as the engine is idling so limit the amount of air being sucked in ~ if the idle goes up before it begins to flood, you've found there is in fact a vacuum leak somewhere .

Remember : when installing and tightening a 6 cylinder manifold, you offer it up to the cylinder head then loosely install the fasteners then tighten them from the center outwards working back and forth .

Rarely will there be fasteners on the very ends of the manifold .
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Old 04-25-2021, 12:32 PM
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Join Date: Dec 2020
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Thatís what I am thinking is that the front carb is not sucking fuel. I pulled the top cover off and I can see fuel in the bowl. Canít really tell how much is actually in there but there is fuel in the bowl. Looks like about 1/2 up the bowl.

I wonder if there is a nest of some sort stuck in the intake manifold. Car sat for 24 years. There is still crap blowing out of the exhaust. I mean if it were stuck in the exhaust side it would surely blow out.
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Old 04-26-2021, 09:54 AM
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Location: Chapel Hill, NC
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What does the Unisyn tell you? Is the front carb drawing about the same as the back? I think this is just a blocked passage in the front carb. Does it run better or different if you spray a little carb cleaner into the primary side of the front carb when it's at idle? The bowl should be nearly full, so your needle valve could be the problem too.
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Old 05-02-2021, 10:25 PM
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Location: Las Vegas & N. Cal
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So ?
(1) what is the Compression Now that you made it run ? each cylinder
( This is a Crucial basic test > the car well only run right if you have good ballenced compression . I always do this first before anything elce and yes when they sit that long
its better to run it before testing most often )
(2) With the Motor running Poor or not and the air cleaner top off looking down the Carb
Throats and accelarating the Motor you can see Gas being pulled from the clusters center area of the Carbs . This tells you if Gas is passing through or not .
Accelator Pumps you can check motor off just pumping them but thats not your basic Prob I don't think .
(3) I hope you found and pulled the " emulsion tubes " when you cleaned the carbs / all the jets and such .

Beyond that if the Car is not pouring out huge amounts of smoke and has good compression ( 135 to 150 ballenced ) it should run good unless you have indeed a unfound Vacume Leak .
Easy Test Vacume : Car outside running just run a garden hose slowley about the Motor
advoiding the Spark plugs and Distributor . Intake Manfold / Carbs / Vacume lines Etc.
If you find a leak you shall know it right away as the water flow hits it > You don't need a Huge Water flow for this

Hope this helps sometimes you just have to countinue onward

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