The Zenith carb is a more expensive carb than the Holley, but they are cheap due to
so many people changing to holley to get the benefit of a mechanical accelerator
pump. The Zenith accelerator pump works on vacuum. Only works when the engine
is running. This carb being set-up for a generater, is set rich on the idle circuit to warm the engine quick to get the generator online. To make it idle all day and not
load up, remove the top cover and on each side of the black rubber pump plunger is a
small brass jet called the Idle Air Bleeds. Drill these bleeds out to .063 thousandths.
This lets more air into the idle circuit.
To make the Zenith accelerate faster, remove the float bowl and gasket from the base.
Look for the 2 small brass jets ( sqirters ) toward the rear of the base. They are angled toward the center of each bore. Drill them out to .043 thousants. This will
give a larger shot of fuel on acceleration. You will notice the difference. The
hesitation will be gone. CHUCK
so many people changing to holley to get the benefit of a mechanical accelerator
pump. The Zenith accelerator pump works on vacuum. Only works when the engine
is running. This carb being set-up for a generater, is set rich on the idle circuit to warm the engine quick to get the generator online. To make it idle all day and not
load up, remove the top cover and on each side of the black rubber pump plunger is a
small brass jet called the Idle Air Bleeds. Drill these bleeds out to .063 thousandths.
This lets more air into the idle circuit.
To make the Zenith accelerate faster, remove the float bowl and gasket from the base.
Look for the 2 small brass jets ( sqirters ) toward the rear of the base. They are angled toward the center of each bore. Drill them out to .043 thousants. This will
give a larger shot of fuel on acceleration. You will notice the difference. The
hesitation will be gone. CHUCK
