56 Carter Carb Problem

[akstraw]

I have a 56 Coupe deVille with a single Carter WCFB 4 bbl carburetor.  Recently (right in front of the registration tent at a car show), the engine stalled while idling, and would not re-start.  There was fuel leaking out of the carburetor - it appeared to be coming out of the passenger side of the throttle body at the throttle shaft.  Prior to that day, I had hundreds of miles (if not a thousand) of trouble-free operation since the carburetor was last touched.

When I removed the carburetor, there was also a puddle of liquid fuel in the intake manifold.  I took apart the carburetor, cleaned it, and adjusted the up and down levels of the floats per the shop manual.  When I re-installed the carburetor, it immediately exhibited the same problem.

I rebuilt the carburetor about two years ago with a NOS Carter Zip Kit, and it is still very clean inside and out.  The brass floats are clean and solid. 

I am looking for ideas on what could be causing this problem.  Has anybody had a similar experience?  Is it possible that the fuel pump could be overpowering the float valves?  It has a NORS stock fuel pump, but a modern canister filter rather than the glass bowl type.

Thanks in advance to any carburetor experts who can weigh in on this.

Andrew
CLC 21467

[Otto Skorzeny]

Hi Andrew,

I also drive a 56 CDV.

It sounds like your carb is percolating. The diaphragm in the accelerator pump may be torn or  not sealing up. If you need a rebuild kit or wish to have your carb professionally rebuilt, call this company. They do excellent work.

Daytona Parts Company
386-427-7108
www.daytonaparts.com
mail@daytonaparts.com

This company assembles nearly all the carburetor kits sold by other suppliers. They have the largest archive of original carburetor blueprints from the original manufacturers in the world. They make kits for virtually every automotive carb made from 1900 to 1980.

They also do top quality rebuilding of carburetors for those who don't wish to do it themselves. Check them out. You'll be impressed.

Ask for Ron Hewitt or Tim Hewitt.


I have recently experienced fuel related trouble with my car. Ethanol in the gasoline has weakened the diaphragm in two fuel pumps. Others I know have had vapor lock trouble as a result of ethanol's higher volatility. Good luck with your repair.

[Shep]

Another often seen possibility is the floats bind on the bowl housing, which is easy to happen on those carbs.  As mentioned check fuel pressure also, 6.5 psi is tops.

[John Washburn CLC 1067 Sadly deceased.]

Andrew,

Couple of comments. Were the zip kip needles rubber tipped? If so due to there age the alcohol in the gas will make these sticky which may cause the problem.

When you pulled it apart you did check to make sure the floats did not have gas in them?

I don't belive the standard fuel pump will over power the needle and seats and the fuel pressure should be around 5 1/2 pounds at the carburetor.

Since it ran well for the last couple of years it sounds like the alcohol in the gas was the culprit, but who knows. Let us know the resolution.

John Washburn with lots of 56 carburetors.

[kelly]

I agree that you need to verify the floats didn,t have any fuel in them.  I installed a factory reman Rochester 4 jet on my 57 .  I worked flawlessly for about 8 months, then it flooded. I also had a puddle in the intake, and moisture showing around the gasket area between the lid and bowl. It all happened pretty fast.
  Upon disassembly, I shook the float from the front bowl, and found it to contain a small amount of liquid...  just enough to cause overflow flooding.
I was successful in fixing the leaking float, but that is another story. Best of luck.
Kelly Martin

[Roger H]

One other trick to try,  occasionally dirt oy somthing may get stuck under the needle and will not leave because the float is constantly trying to close and keeps it pinched
What you do is  pinch off the fuel supply line somewhere( or disconnect it and plug it) and run the car untill it runs out all the fuel in the carb and stalls. than release the line and start as normal.  Hopefully if something was stuck in the needle / seat area it will be flushed out.
It sure sounds like just a leaking needle valve
Roger

[akstraw]

Thanks for all your thoughts.  I went through the carburetor twice, and my conclusion is that I either had a float binding on the side of the bowl, or that the leather seal on the accelerator pump piston was bad.  In any case, the carb is back on the car, and it ran great for over 100 miles last weekend with no evidence of leaking or flooding.  I learned a lot about my Carter carburetor in the process of correcting this problem.

Andy
CLC 21467