I have a 318 engine with a carter 2425 2 barrel carb on it. The original fuel system was plumbed with a return line from the filter back to the tank. I am gong to eliminate the mechanical pump and install an electric pump. Will I be able to eliminate the return line and just use a filter without the return line. What was the purpose for the return line anyways? Was it to lower the pressure at the carb?

 

I think it depends on the fuel pump. Normally you need a return line for excess fuel......

 

I've ran across those 3 nipple filters before while researching other stuff online. I know their used on other applications but, I've never seen them on a Chrysler engine.

From what I understand, this is a simple way to prevent vapor lock in hot climates by keeping the fuel moving in the lines even when the needle is closed on the carburetor inlet.

But, it matters how this style of filter is orientated in the system. If done incorrectly fuel will favor the return line instead of the carburetor inlet all the time.

I'd imagine if the fuel system looks stock and was working before, I don't know why an electric pump operating in the same psi range as the mechanical pump wouldn't work. But, I could be wrong.

If the return looks like something that was added by a previous owner you could try running it with the return capped off for testing. But, I'm pretty sure it will work. One of my trucks has a 318 with a mechanical pump and there never was a return line.

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An electric pump should be at the rear of the vehicle, then a filter without a return, after that a regulator of needed, some fuel systems incorporate a return fuel regulator that bypasses excess fuel pressure back to the tank and these are usually at the carburetor.

 

This is a basket case project. Just trying to get it running for now. I wanted to use an electric pump I already had. I hooked it up without the bypass line and the carb flooded over. Not sure if the carb is bad or if the return line is needed. Never did understand why some cars used the return and others don't. Didn't know if Carter 2 barrel carbs required one.

 

The fuel pump determines if you need a regulator, if it pumps over 7-8 psi, your carb might need to be pulled apart and cleaned.

 

I think this Mr Gasket fuel pump is only good for about 5 lbs. This engine has been sitting for 2 years. I will check out the carb first. Just wanted to get it running so I move it out of the barn once in a while.

 

You can delete it. I always thought is was a crappy after thought anyway....