PLUG-SEAL 1073136 - Caterpillar

Introduction
The following procedure will determine if the accumulator for the ride control system is charged to the appropriate pressure. The accumulator is located on the boom cylinder.
Dry nitrogen is the only gas approved for use in the accumulators. The charging of oxygen gas in an accumulator will cause an explosion. An explosion can be eliminated by using nitrogen gas cylinders with standard CGA (Compressed Gas Association, Inc.) No. 580 connectors. When nitrogen gas is ordered, make sure to order the cylinders with CGA No. 580 connectors.Do not rely on color codes or other methods of identification to tell the difference between nitrogen and oxygen cylinders. In any application, never use an adapter to connect your nitrogen charging group to a valve outlet used on both nitrogen, oxygen, or other gas cylinders. BE SURE YOU USE DRY NITROGEN (99.8% purity).
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Refer to Special Publication, NENG2500, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat products.Dispose of all fluids according to local regulations and mandates.
Machine Preparation
Clear all personnel from the machine and from the area around the machine.
Start the engine.
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Engine speed dial
Set the engine speed dial at "10".
Lower the left console.
Position the machine on level ground. Check the visibility and adjust the mirrors for the best vision close to the machine.
Fully depress the service brake pedal until the service brake pedal locks mechanically.
Increase the hydraulic oil temperature to 46 to 80° C (115 to 176° F).
Lower the stabilizers and the blade tip.
Fully extend the bucket cylinder and place the worktool on the ground.
Stop the engine.
Release the pressure in the hydraulic system. Note: Refer to Testing and Adjusting, "System Pressure - Release".
Turn the start switch to the ON position. Testing and Charging the Accumulator (Nitrogen Gas Charge)
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Refer to Special Instruction, REHS5464, "Accumulator Discharging and Charging Procedures" for the required tooling, and the testing and charging procedure. Note: Do not attempt to charge the accumulator until all pressure has been removed from the ride control accumulator.
Refer Table 1 for the correct charge pressure. Worksheet
Gas pressure is variable with temperature. Check the temperature of the air around the accumulator. In order to check the amount of charge in an accumulator, the accumulator must be at the same temperature as the surrounding air.Note: The temperature of the accumulator may change as the accumulator is being charged due to the expansion or compression of the nitrogen charge. Charging the accumulator in several steps may be necessary in order to ensure a correct charge.
Table 1
"Accumulator (Ride Control) - Test and Charge"
Date: Machine Serial Number:
Specification(1) Actual
Item Temperature of Gas Model
M316D M318D
M322D
Ride Control Accumulator 0° C (32° F) 6,000 kPa (870 psi) 6,500 kPa (943 psi)
20° C (68° F) 6,500 kPa (943 psi) 7,000 kPa