We are in the process of rebuilding an Edelbrock 4 barrel carburetor. Before closing up the carburetor I want to test the accelerator pump circuit.
The accelerator pump circuit is what give the engine an extra squirt of gas when stepping on the accelerator. An accelerator pump circuit that isn’t working well can cause hesitation, or bog.
- Fill the float bowl with mineral spirits. I don’t use gas because of the fire hazard.
- Insert the accelerator pump.
- Push the pump to the bottom of the well and raise up to see if the fluid fills up the well.
- With the main discharge check weight and ball removed push the pump down. Fluid should come out of the discharge top.
- Replace the check ball and weight. Hold the weight down with a drift punch.
- Pump the accelerator pump again. Nothing should come out the top. You should feel a bit of pressure when pressing down on the pump.
- Tap the check ball lightly to form a good seal. Too hard and you have ruined your carburetor.
- Pump the accelerator pump again. You should get 2 good squirts out of the discharge.