Our '94 Forman is 1.3L carbureted. I recently got it running again after it was parked for a few years. Ran great, but the idle was lumpy at best. Looking down into the primary venturi at idle, I could see raw gasoline dripping onto the throttle valve from the float chamber overflow. I assumed that the float needle valve was not closing properly when the float chamber was full, so I bought a rebuild kit and installed it. Same problem. 

To make a long story short, The problem was that the return line to the fuel tank was blocked and when the float chamber was full, fuel was not being sent back to the tank. The excess fuel pressure was pushing gas past the needle valve and overfilling the float bowl. I found that the metal return line tubing was crushed under the floorboard. I cut out the defective section of the tube, replaced it, and now the engine idles perfectly. Just a heads-up for anyone who may have the same problem.

 

- JAMES

On 01/09/2019 at 19:32, JAMES399 said:

I found that the metal return line tubing was crushed under the floorboard.

That is something new. The odds for that to happen are slim. I added your story to my technical notebook.