- 1). Check the clearance between the pump diaphragm arm and the adjustment screw assembly found on the forward mounted fuel bowl. Ensure the arm is slightly touching the bottom of the operating level screw. Adjust the nut to touch the arm by holding the bottom nut with one wrench while turning the top nut with another wrench until the arm and bottom nut meet.
- 2). Disengage the fast idle cam lever, indicated by its red color, by locating it on the passenger side of the choke tower assembly and pushing it down with your finger until it clicks.
- 3). Hold the throttle lever to the wide open position. Slip the feeler gauge between the pump diaphragm arm and the bottom of the adjustment screw. Proper clearance will force the pump arm down slightly.
- 4). Insert a screwdriver through the top of the choke tower and remove the screw than secures the pump nozzles, one for each pump. Use a pair of needle nose pliers to pull the nozzles out of the choke tower and replace them with larger or smaller nozzles, depending on the acceleration characteristics of the engine. Bogging will require smaller nozzles, while a lean backfire will require larger nozzles.
- 5). Repeat the above steps exactly for the secondary accelerator pump found rearward of the choke tower.
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