All models use 3 long air horn screws located in the primary and secondary venturi area of which 2 longer screws (nos 2 and 3) hold the vent and screen assembly in place. 2 short screws are located on the fuel inlet side (nos 5 and 6) and 1 screw (no 1) is located beneath the hot idle compensator valve (if used).

Truck applications use 1 additional large head screw (no 7).

All air horn screws must be tightened evenly and securly following sequence shown.