BLOCK AS-FUSE 3914516 - Caterpillar

Table 1
Requirements for Fuel Pressure To the Gas Pressure Regulator
Fuel System Pressure
Low pressure gas 10.3 to 34 2 kPa (1.50 to 5 0.25 psi) Pressure of the Fuel Supply To the Carburetor
The gas pressure regulator maintains a pressure differential between the air and the fuel that is supplied to the carburetor. After setting, the gas pressure regulator will maintain the pressure differential in response to changes in the air pressure.Use a water manometer for measuring the pressure differential. Obtain the measurement when the engine is operating at high idle rpm. After a load is applied, the fuel pressure will usually decrease by approximately 0.1 to 0.25 kPa (0.50 to 1 inches of H2O). If the performance of the gas pressure regulator is erratic, the gas pressure regulator may require service.Natural Gas
Set the pressure of the fuel supply to a maximum of 1 to 1.2 kPa (4 to 4.5 inches of H2O) HIGHER than the ambient air pressure.