Carb issue? Not a vacuum issue?

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Mar 16, 2013
Installed newly rebuilt Aisin carb from Old carb was was ok but had a broken screw on the choke valve. It ran, but had trouble starting so we replaced the carb. Now it starts fine, idles fine, accelerates fine, but will not run at 'cruise' speeds. At mid throttle it sputters and blubbers unless the choke is pulled halfway out. Have had the whole intake manifold off, new brake booster, bypassed all smog emissions, thoroughly checked but...I find no vacuum leaks whatsoever. Help???
Some things to check: {sounds like it is running out of fuel--especially if it always does it at the same point}
Fuel pump(diaphragm)
Is the float bowl showing good fuel level?(will prob show ok at idle--fuel filter?-or needle valve screen?)
Does it do it regardless of the engine temp?(vacuum leak-but sounds like you checked)
Do the Pin_Head paper clip test on the secondary to make sure it is opening ok(see you tube video on secondary diaphragm info)
Others will doubtless have more detailed t'shooting ideas than me----
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If pulling the choke works, it's not a fuel delivery issue. Disregard paper-clip test as a '72 would have a mechanical secondary...
I might pull it apart to see what secondary jet is in there.
Have you ever put a vacuum gauge to the manifold?
is the solenoid correctly wired ?
If it idles fine, I assume the solenoid is working...

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