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The diaphragm pump from Kanters was a 'fresh' rebuild as I had to wait for it to come into stock, so I am presuming it should be fine as I trust Kanters to provide quality components in their rebuilds. Re the pressure regulator, I did purchase one, I believe made by Holley and it was around $50, so think it should be okay quality. It is a 1-4 PSI range and I had the fuel going through it before it went into the engine pump to minimize the pressure on the diaphragm for the aforementioned reasons. If everything is working the way it's supposed to, I should be okay. Thanks for the info. Chris

Although typically, pushing fuel using an electric pump is preferred, I've often placed it at the carburetor, replacing the filter where it then sucks through the original pump. Of course, I have also always used the solenoid type. I have a vane type but use it only on an external tank used for testing engines without using the built-in tank or pump at all.

Most pumps self-regulate the pressure too so shut off once it's sufficient but again, my primary experience is with the solenoid type so I don't know if the vane types do that or not. However, looking online I see that the vane type pump is available in different pressures so you works definitely need to check which yours is. Too high a pressure would cause problems.

As a general rule for my own cars, though, an electric pump is there only as a temporary measure until I get sorted out whatever problem is making it need it in the first place! Once fixed, it is removed.

An electric pump can be placed just about anywhere in the fuel line. The preferred location is as close to the tank as possible. The reason for this is to pressurize as much of the fuel line as possible to avoid vapor locking. Vapor lock occurs in the non-pressurized part of the fuel system. No experience placing the pump close to the carburetor and will rely on the recommendations of those who have done it this way.

Also John, those little pumps push fuel a lot better than they vacuum it. Interesting point on vapour lock, I did not know that it only occurred in the non-pressurized portion of the fuel line. The more I learn about 'vapour-lock' the more it seems like kind of a 'phantom symptom', a blanket explanation for bad performance. My understanding of it, is the fuel gets hot enough in the line to vapourize and the diaphragm pumps won't pump vapour, thus 'vapour lock'. Based on what you are saying, this would have to happen between the tank and the fuel pump inlet and I can't imagine a scenario where the fuel could get hot enough to 'boil' south of the pump intake. It shouldn't get that hot that far away from the manifold, should it??? Between the pump and the carb, it sure can, but then the fuel is under pressure - shouldn't vaporize, right????

Gasoline on the suction side will have a depressed boiling point, thus the propensity to vaporize faster than the same liquid would have at atmospheric or elevated pressures.

I have heard for years and many times the electric pumps push better than they suck. This may be true, but no facts have come forth as far as I know to prove this claim. Anyone?

This off the 'H&H Classic Car' website. In their instructions on how to install an electric fuel pump, they list the 'DON'Ts' and this is the #1 caution:
Quote:
For what it's worth??...... Chris

JW, just as a generalization almost all mechanical pumps are better pushers than pullers. You might want to browse some engineering references.

Looking on Google, I came across a small device that will run the electric pump for only three seconds when the ignition is turned on, then shut it off. It is available in both 12v and 6v models but no mention of polarity. Of course, it would be better with the solenoid pump or a vane pump with bypass, some of which have it built-in.

Looking on Google, I came across a small device that will run the electric pump for only three seconds when the ignition is turned on, then shut it off.

Is it called a Toggle Switch ?