Triumph Repair: Weber carb on1972 Spitfire, float chamber, weber carb

Question
I have two questions about the Weber carb. #40DCOE147 on my 72 Triumph Spitfire with a modified engine.

1. At idle and just off of idle I get a backfire (popping) through the carburetor. Any idea on what is causing this?

2. After the engine is warmed up and I shut off the engine, I get gasoline dripping from the back of the carburetor just under the choke mechanism. It drips for about a minute.

As soon as you start the car back up, the dripping quits. Any ideas on this problem?

Answer
Hi Alfred,
I doubt that the popping has much to do with the carburetor although you can try turning the idle mixture screw a little richer. If that don't correct it, you need to do a cylinder leak down test and double check the ignition timing.
As for fuel dripping after you shut the car off my guess is either the float level is too high, the float chamber vent has a problem or you just have a leaking needle %26 seat in the float chamber.
Howard