Ultra-rich Fuel Mixture and Flooding Inlet Manifold Drains

[Nivens]

In my experience I have had several "new" parts which hove not performed properly in service as others have suggested. From the discussion, it seems the carb floats are not controlling the fuel level in the carburetor's fuel supply properly. I would suspect (1) float failure (2) float to needle adjustment, or (3) the needle to seat is fowling so it is not shutting off the flow when the float is full up. Carburetor floats are normally quite reliable, but they can fail in service also. All it takes is a pin hole leak. lf I experienced your situation, I would remove the problem carb(s) and go through the needle and float assemblies meticulously. Make certain everything is clean and everything operates freely. Check the float for leakage (any is unacceptable), check the vents, check the needle setting to be certain the needle is seated fully when the float is raised to the full position. I typically use a blow hose pressurized by mouth to be certain the needle is fully seated and not leaking any air. If everything inside checks out, reassemble the carb(s) on the bench, invert the carb and use the mouth blow hose again to see if there is any air leak by. If so, the float is hanging. That would mean the float is hanging on something and is not freely operating. It could be bent in the hinge, simply the wrong float for the carb, or an impingement somewhere inside the carb float bowl.

 

[Bob_Spidell]

This just came through my FB scroll from 'Dr. Carburetor Alan Vinegar' and is, perhaps, germane to the discussion:

"Not all float bowl lids are the same. Most HD8s use a taller lid and the pedestals inside are taller. As a result the float forks is different as seen in the picture. The previous rebuilder did some nasty bends to the fork and using Grose jets miraculously it worked. I picked up the correct forks from Autofarm who specializes in Healey Parts."

 

[Patrick67BJ8]

If you have the HD type of carbs, you probably only need the jet diaphragms changed. They are a rubber material and crack causing gas to escape through them.

 

[Walter74]

I now replaced the floats, the needle valves, the jet bearings and the jets. Unfortunately no change in the flooding. Mostly the left drain from the air intake is leaking fuel from cold start. I am really lost what to do next….

 

[Walter74]

I mean the left drain of the inlet manifold of course

 

[John Turney]

Does this happen with the choke on, off or both?

 

[Michael Oritt]

Walter--

Reviewing the posts I see from #24 that you added a fuel pressure regulator which I believe you set to 2 psi and that did not help. What kind of fuel pump are you using and can you send a picture showing where/how the fuel pressure regulator is installed?

This topic/problem sure has legs!

 

[Walter74]

Does this happen with the choke on, off or both?

I have the choke cables completely disconnected.

 

[Walter74]

Walter--

Reviewing the posts I see from #24 that you added a fuel pressure regulator which I believe you set to 2 psi and that did not help. What kind of fuel pump are you using and can you send a picture showing where/how the fuel pressure regulator is installed?

This topic/problem sure has legs!

The pump is a Pierburg 06t289. Attached you can find a picture of the Filter King regulator installed and set at 2Psi

 

[Michael Oritt]

Walter--

At this point if this were my car I would remove the Pierburg fuel pump and install an SU.
In any case I hope you eventually get this problem solved and when you do let us know what was the issue and the fix.

 

[johnea]

Maybe fuel find its way around the threads of the float valve. It would fill up the float bowl even if the float shuts off the fuel supply ….