Fuel pressure should remain fairly constant at all times. If your gauge is showing that it's dropping to 0 at times, then there is a problem somewhere, possibly the gauge itself.
A carburetted engine doesn't use a constant flow of fuel(thru the fuel line), like an injected engine does, so the fuel requirement at idle should be very small...once the fuel bowl is full, the pressure should remain stable, until the float level drops enough to allow more fuel into the bowl, at which time you
might see a small drop in pressure for a second or so.
Is your gauge
before, or
after the regulator?
(I know...it's a silly question, but....ya never know...)
Electric, or mechanical fuel pump?
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Joel Adams
C3VR Lifetime Member #56
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