Mechanical fuel pump???

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jhdeval

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Okay I have a slant six with mechanical fuel pump. I drive the car EVERYDAY but every morning I pump 2-3 times kick it over and let it idle for a second then it dies. I kick it over after 2-3 more pumps and it is usually good.

My question is since I drive it everyday shouldn't I expect the system to maintain pressure? I suspect the reason I have to pump multiple times is because the fuel bowl is being emptied over night.

My next question is how do I know if my fuel pump is bad? What kind of pressure should I expect and how do I measure it? Running or cold?
 
Okay I have a slant six with mechanical fuel pump. I drive the car EVERYDAY but every morning I pump 2-3 times kick it over and let it idle for a second then it dies. I kick it over after 2-3 more pumps and it is usually good.

My question is since I drive it everyday shouldn't I expect the system to maintain pressure? I suspect the reason I have to pump multiple times is because the fuel bowl is being emptied over night.

My next question is how do I know if my fuel pump is bad? What kind of pressure should I expect and how do I measure it? Running or cold?

the reason it starts then dies is the fuel bowl still has fuel but the pump has to push fuel up the line to the carburator then it will start again

its not likely you will find a pressure problem with the pump (runs 2-7 PSI running any temprature)

its more likely the anti-drainback valve (or checkvalve) is gettting bad

personally I like a small electric fuel pump (not the holley or expensive pumps) the ones I buy are about $40 and are rated for 5-7 PSI

that way soon as you turn the key the engine will start and most times a choke is not needed! it also helps with vapor lock issues

I run carquest E8012S pumps on carburated vehicles
 
I'm wondering if you have a tank vent problem

Try loosening the cap over a couple of nights, see if that changes things.
 
67Dart273 You think the vent is blocked? I do know it had been previously blocked. When I pulled the tank I made sure the vent was under the rubber floor gasket but not into the tank gasket. I can double check and see if it has moved.
 
Is the choke adjusted properly? Thats what I'd look at first. If the choke pull off is opening the choke too far, what you describe can happen.

The fuel bowl cannot empty, it would have to evaporate, unless you had some sort of leak in the bottom of the bowl. The fuel would either be in the manifold, or dripping on the engine.

Any doubts about the fuel pump, replace it,they're cheap.
 
How do you adjust the choke? I have a mechanical choke that uses a stepped cam to a heat sensitive coil attached to the exhaust manifold. I have adjusted the idles which uses the stepped cam and a screw for the high idle.
 
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