70 Blazer, 350, 300hp crate motor, have replaced fuel pump, installed hei
ignition, 4bbl Rochester carb has been rebuilt.
I've got an occasional "loading up" at lower rpm's, 2000 or below. Engine
will die at idle. This has been occurring before and after a new engine and
later elect. ign. Anyone know what might cause this Rochester 4bbl to do
this? OR, could it be a non vented gas cap causing a pressure build-up to
blow through the fp and past the main jets? I frequently have a pressure
build up when I remove the cap to refuel (which is not too often with a
Do you mean it's too rich and floods out at times?
This has been occurring before and after a new engine and
The needle seat, needles, floats, etc in those commonly stick for one
thing. Kind of sounds like the float or needle is sticking and
flooding out maybe. Do you see gas dribble from the carb, or smell a
strong gas odor when this happens?
OR, could it be a non vented gas cap causing a pressure build-up to
I kinda doubt it. Usually in a case like that, the tank collapses, and
you starve for fuel, rather than have too much pressure. I'd make sure
the cap is correct for the truck, but usually having some pressure is
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