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I've been driving the '52 300 for several months now and noticed its not performing as well as it should. It seems the accelerator pump gets stuck sometimes and then it will suddenly kick in. The engine also stalls out like a light when I go full throttle. Additionally the gas mileage has been poor.

I want to rebuild the 2 barrel WGD but I got to thinking it may run better with the 4 barrel. Would the 4 barrel from a 1953 work on a 1952? Would the 4 barrel give the same gas mileage? And do I need the manifold or anytging else to convert to 4 barrels? Thank you all for the help.

John

A good carburetor rebuild is perhaps in order, but first why not check the manifold vacuum at idle - what you describe can be the result of a vacuum leak, at the distributor vacuum advance or elsewhere (manifold gaskets, vacuum booster pump, wiper hose connections, etc. An engine in good mechanical internal condition and in a good state of tune should give 18-20 inches of vacuum at idle.

The engine has been rebuilt. The only visible leak is the carburetor body gasket. I hooked up my vacuum gauge and it read 10-12."

I suspect if you solve the problem of the very low manifold vacuum, you'll solve your problem. 10-12 inches of vacuum is TERRIBLE. First I' make sure the ignition timing is on specification, then adjust the carburetor idle mixtures to give maximum vacuum at idle but without opening the mixture screw further than the point of maximum vacuum. If that doesn't give you 18 inches or more, start looking for a vacuum leak. Likely places are the vacuum booster pump, intake manifold gaskets, or broken loose vacuum hoses. The distributor vacuum advance might also be a source of a leak but I wonder if it alone could give such a large vacuum drop. Also if you 52 has Easamatic brakes, a leak in that vacuum circuit is also a good possibility.

It was a vacuum leak in a hose. Now it's pulling 21". I ran it through first and second wide open and the car flew. It's got enough power now. I think I need to lower the idle speed now. Thanks for pointing me in the right direction.