Last night, solved a 2 month old mystery of why a '72 Midget wouldn't stay running. Turns out it was a bit of excess wire on the clip that the float valve was suspended by, was hanging up on the tab at the back side of the float, essentially holding the float valve closed.
I pulled the carburetor (Weber 32/36) and took the upper section off.
First observations, the internal filter was clean and not blocked by anything but there was very little gas in the fuel bowl.
Before starting a full teardown, it seemed the floats rested higher than they should have been. When I originally put the carb back together, I made sure I had the floats adjusted correctly. I even made a small gauge to make it easier to confirm.
I retrieved the gauge, re-checked the float height and sure enough, the floats were resting about 5-6 mm too high.
The problem was on the float valve, the thin wire clip that it hangs from has an extra length of wire that sticks out horizontally. There’s about ¼” of excess wire. The way I put the float valve in, this excess wire was pointing toward the float pivot pin, and (I’m assuming) got hung up on the downward rear tab that’s on the floats (the carb has brass floats) and restricted the float valve from opening.
A quick fix was to just turn the float valve around 180 degrees, having the excess wire point toward the fuel bowl.
Did the necessary cleaning and ensuring the carb passages were clear, put it back together and back on the car; and after 10 seconds or so of cranking, the engine started and idled fine. I let it idle for about 3-4 minutes, rev’d it a few times, shut it down and it restarted easily.
It was too late to take it for a test drive, but this evening, I’ll test it out around the back field to see if it’s finally fixed.