PUMP GP-VIBRATORY 1193135 - Caterpillar

In any application, never use an adapter to connect the nitrogen charging equipment to a valve that can be used on oxygen or other gas cylinders. Be sure you are using dry nitrogen.
Make reference to warning on first page of Push-Pull Testing And Adjusting section.
Be sure the engine has not been running for a minimum of five minutes. This is enough time to let the oil in the accumulator bleed down. The accumulator piston must be on the bottom of the cylinder to be sure that the pressure of the nitrogen charge is correct.The rear accumulator (A) has a charge of approximately 3100 kPa (450 psi). The front accumulator (B) has a charge of approximately 8270 kPa (1200 psi).Gas pressure is variable with temperature. The accumulator must be at the same temperature as the air around it before it can be checked or charged. Use the chart for getting the correct nitrogen charge.
Accumulator
(A) Rear accumulator (low pressure). (B) Front accumulator (high pressure).Checking Nitrogen Charge In An Accumulator
Nitrogen Charging Group
(1) Pressure gauge. (2) Connection to nitrogen cylinder valve. (3) Regulator assembly. (4) Valve. (5) Pressure gauge. (6) Pressure regulating screws. (7) Valve handle. (8) Chuck.1. Remove the cap from the valve assembly on the accumulator.2. Use the 13 800 kPa (2000 psi) gauge (5) to check the nitrogen charge in the accumulator.3. Install chuck (8) on the valve of the accumulator.4. Turn valve (7) on chuck (8) completely in (clockwise). Check the temperature of the air around the accumulator. The pressure on the gauge must be inside the tolerances shown on the chart.5. If the pressure reading on the gauge is too high, lower the pressure by slowly opening valve (4).6. If the pressure reading in the gauge is too low, charge the accumulator.Charging An Accumulator
1. Connect the hose from the nitrogen cylinder to valve (4).2. Close valve (4) and open the valve on the nitrogen cylinder. Make an adjustment to screw (6) on the regulator assembly until gauge (1) is at the pressure needed to correctly charge the accumulator. Use the chart as a reference for the correct charging pressure.3. Open valve (4) and charge the accumulator. Turn valve (4) OFF. If the pressure on gauge (5) is the same as gauge (1) and does not change, the accumulator is correctly charged. If there is a decrease in pressure on gauge (5), open valve (4) and let more nitrogen go to the accumulator. Do this procedure as many times as necessary until the pressure on gauge (5) is the same as gauge (1) and does not change when valve (4) is turned OFF.4. Close the valve (4). Close the valve on the nitrogen cylinder.5. Open valve (7) on chuck (8) completely (counterclockwise).6. Remove the test equipment.Charging A Rebuilt Accumulator
It is necessary to remove all air from the nitrogen end of the accumulator. When the accumulator is rebuilt, put approximately 1.9 L (2 qt) of SAE 10W hydraulic oil in the nitrogen end of the accumulator. This oil