HUB 6P2346 - Caterpillar

Gas Supply to the Gas Pressure Regulator
To prevent particles from entering the engine, install a 1 micron fuel filter 1 m (3 ft) before the gas pressure regulator. Install a 321-6970 Fuel Filter Gp with the 4P-4720 Fuel Filter Element in the gas supply line to the regulator.Also install a pressure gauge on each side of the fuel filter to monitor filter restriction. To facilitate servicing of the filter, a shutoff valve should be installed on the supply side of the filter.For low-pressure gas, a supply pressure of 10 kPa to 35 kPa (1.5 psi to 5 psi) is required for the gas pressure regulator with 24 kPa to 35 kPa (3.5 psi to 5 psi) Optimal.Fluctuations of the supply pressure may affect the air/fuel ratio for the engine. For low-pressure gas fuel systems, the maximum fluctuation that is allowed in the supply gas pressure to the engine is 1.7 kPa ( 0.25 psi).
Use only properly designated Caterpillar gas pressure regulators.
Check the Installation of the Gas Pressure Regulator
Illustration 1 g02411864
Line connections to the gas pressure regulator
(1) Balance line
(2) Compensation sensing lineCarefully inspect the condition of balance line (1) and compensating line (2) at both ends. Ensure that the line fittings are not leaking.Ensure that the lines are not kinked or damaged. Damage to one of the lines could compromise the operation of the gas pressure regulator. If the condition of either of the lines is questionable, replace the line.Adjusting the Gas Pressure Regulator
The gas pressure regulator maintains a pressure differential between the air and the fuel that is supplied to the carburetor. After the initial setup, the gas pressure regulator will maintain the pressure differential in response to changes in the carburetor air pressure. Refer to the "High and Lower Heating Value Fuels" graphs to obtain the differential pressure setting for the correct air/fuel ratio. The value obtained from the graph