DDK - Die Deutschen Klassiker

Hi all, one venturi in my RH solex 40 for cylinder 1 keeps filling with fuel. Its a constant drip, drip that leaves a little puddle of fuel sat on top of the butterfly. I have stripped and cleaned everything and fitted new gaskets but cant stop the problem.

I have checked the fuel pump pressure and actually reduced it slightly. I have fitted a new needle check valve for the float and the float level is bang on.

Any ideas?

Did you use the special tool to set the level? It would seem the the air correction jets can siphon fuel, likewise the centre piece across the venturi which delivers fuel at high rpm from the main jet circuit can leak?

The fuel pressure should be around 3.0 psi.

The float movement can in somecases according to some be sticky in its movement which when you have changed the needle valves and set the level makes you think all is okay but the float siezes maybe just before making the needle valve, causing fuel to get past.

The float level seems not so easy to do without the tool fuel level gauge.

Does it only happen with the engine hot?

Its along time since I did anything on Solex but I looked on the troubleshooting pages on the registry site. Put in "Solex" into the search box and you will see you are not the first with leaking problems like this.

Look on all the listed threads itemised when you will then see the solex answers. Some of them I have very briefly!!!!! itemised above.

Well worth your time to look it might just help you.

Roy

Just another point one of the guys listed on search area I told you about had petrol leaking the same as you into the right side venturi ( no.1 cylinder ) It would seem fuel was coming into venturi from the metal bar linked to main jet across the venturi which is called by one person the "pre-atomiser" According then they think the float level is incorrect and should be checked again. The last part of this thread will tell you how to do this without a special tool if you didn't have one.

Something I learned was it would seem the fuel pressure is different from Zenith to Solex carbs.

Roy

fixed it again. The needle valve was duff. I put the old one on and ta da no leak. But I cant get the engine to idle below 2000rpm.