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Ok guys i have a 1967 chevelle with a 454 edelbrock 600 echock. electric fuel pump and regulator. Fuel pressure set at 6 lbs but after shutting down engine hot the pressure rises to 9 - 10 lbs. and have to turn engine over several time to start and floods but after cooling down pressure drops down to 0 cranks on first turn over what can be done to get pressure to drop after engine is cut off hot or is this norm. thanks for any help
 

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The fuel pressure holding at higher than running, when down, says your needle and seat are holding fine.

You have a heat soak, or hot starting issue. Research things like carb spacers made of wood or phenolic. Your gas in your bowl is vaporizing and over enriching the engine, pisses it off.

The fuel pressure dropping to Zero while down is caused by the gasoline contracting as it cools(plus it also just boiled off some). And maybe bleeding a little through the needle or something but irregardless going from flooded at 9(needle holding) to starts at zero(fuel just went somewhere) does not jibe in this instance if I read your problem right..

Regulators have a characteristic called "droop". It is actually a symptom of being the cheapest apparatus that can be built and still do the job.:)
What regulator droop is, is the difference between the static and dynamic setpoints and it is inherent in almost all regulators. And I work on natural gas engines with regulators that can cost over $3000(not mis-typed either). So rising to 9 static from a dynamic of 6 just says your regulator has a lot of droop percentage wise but not a terrible bunch pressure-wise. A NG regulator working in the 125# range would normally have about a 10# droop.

Either that or your regulator is a piece of crap, non-existant, or something like that. But 9 and flooded and Zero and starts don't go together in this instance due to the fuel boiling off causing it.

The fuel in the bowl is NOT pressurized, AND there is an air gap inbetween the fuel level and the fuel inlet.

edit: if you have an electric pump you could shut it off with an on/off switch a few seconds before killing the engine.
 
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