Fuel flow, spark plugs say way rich

[pwlovely]

Recently purchased a 1947 Lincoln convertible - rebuilt engine. From the looks of the plugs and the decreased power I assume the fuel mixture is too rich. The car idles well but I do sense a miss that could arise from the (new) fouled plugs and decreased power during driving up a hill (again maybe the fouled plugs both banks). I'll check the accelerator pump level to see that it is set on moderate temperatures, seems applicable for Oklahoma at this time of the year. I'll also check the idle speed adjustment screw.  I do not know if the carburetor was ever rebuilt, e.g. the jets and applicable originality of the same.

 

If the above does not solve the problem then on to checking points, condenser, radio suppressor, etc.

 

have I missed anything?

 

Thanks for the help.

[Ken/Alabama]

Bad power valve in Carburetor

[pwlovely]

Is a power valve the same as an economizer valve? The latter is the only value I see in a diagram of the carb. I'm looking at the Service Manual for Ford, Lincoln, Mercury - 1946 to 1948, or, if not, can you point me to a book or Internet site to look at. Thanks Ken.

[carbking]

The power valve and the economizer valve are two different names for an enrichment valve.

 

Some call it a power valve, as it is opened generally under wide open throttle to enrich the mixture for power.

 

Some call it an economizer valve, as it is normally closed, allowing smaller main jets to deliver better economy at "cruise".

 

EDIT: found this thread via search, and read the last post first. Assuming you have the original Holley carb, the economizer valve is probably not the culprit. The Holley design has the outlet for the economizer valve dumping directly into the throttle area. If it fails, generally will be so much extra fuel the engine will not run. Not saying it couldn't be the valve, but Ford ignition is much more likely to be the issue.

 

Jon.

Edited April 17, 2019 by carbking (see edit history)

[pwlovely]

Is this a part that comes with a rebuild kit? I looked at Boos-Herrill but can't tell what comes with the kit. Any and all advice/sources are appreciated.

 

Thanks Jon 

[19tom40]

A power valve will come with the kit, but you will be taking a chance that it will be correct for your carburetor. Some kits come with a correct rated power valve, but the seat is for the later carburetors and will leak when installed in your carburetor.

 

The kits from Daytona Parts have a power valve that will seat in your carburetor and it will open at the correct vacuum reading. The parts in the kit are Ethanol resistant for long life.

https://daytonaparts.com/?gclid=CjwKCAjwhLHaBRAGEiwAHCgG3u7nnmZGE5zNW2bf03GMKp4NJMGepuewjC_60Nk-LNP-UyMO_WbIOxoCNE0QAvD_BwE

 

I strongly recommend that you have your carburetor rebuilt by Charley Schwendler in NY. Phone number is 716/662-9159.

When he rebuild a carburetor he machines the seat for the power valve and the the base of the bowl, so that you get a good vacuum seal, the power valve operates correctly and you can drive your car without worrying.