Zenith 28 IFT 1-Barrel: Operation: Anti-Percolation
After engine has been turned off, heat remaining in the assembly does not dissipate immediately. To prevent a "Percolating" effect from the vaporization of fuel remaining in the discharge tube, a chamber is provided, with a calibrated air bleed drilled in the upper part. In this chamber, the vaporized fuel condenses, and returns to carburetor bowl. To further control this vaporization, thermal insulation is provided by a leather gasket.