PIN AS 8V5481 - Caterpillar

Additional Information
Additional Test Procedures for 789 Off Highway Trucks
The steering pump will recharge the accumulators after every 30 to 40 seconds. This is due to the thermal purge that is internal to the steering valve. The thermal purge circulates warm oil through the valves in order to prevent thermal shock.
Personal injury can result from hydraulic oil pressure and hot oil.Hydraulic oil pressure can remain in the hydraulic system after the engine has been stopped. Serious injury can be caused if this pressure is not released before any service is done on the hydraulic system.Make sure all of the work tools have been lowered to the ground, and the oil is cool before removing any components or lines. Remove the oil filler cap only when the engine is stopped, and the filler cap is cool enough to touch with your bare hand.
Personal injury or death can result from improperly checking for a leak.Always use a board or cardboard when checking for a leak. Escaping air or fluid under pressure, even a pin-hole size leak, can penetrate body tissue causing serious injury, and possible death.If fluid is injected into your skin, it must be treated immediately by a doctor familiar with this type of injury.
The charging of the accumulators creates a load change that affects the cylinder cutout test. The following procedure will keep the steering pump on in order to prevent a load change.
Illustration 3 g00773479
(1) Accumulator charging valve (2) Drain line (3) Elbow
Locate accumulator charging valve (1) .
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.
Disconnect drain line (2) from elbow (3) that is installed in the accumulator charging valve.
Use 6V-9508 Face Seal Plug and 6V-8397 O-Ring Seal in order to plug the drain line that is disconnected from the accumulator charging valve.
Use 6V-9829 Cap As in order to cap the elbow.
Perform the cylinder cutout test.
After the cylinder cutout test, reconnect the drain line to the accumulator charging valve.Note: If the warning light for the Steering Oil Temperature activates, stop the cylinder cutout test and reconnect the drain line. Allow the steering oil temperature to return to normal temperature before you attempt to rerun the cylinder cutout test.Additional Test Procedures for 1500 rpm and 1800 rpm Generator Set Engines
The operation of a 1500 rpm generator or 1800 rpm generator at the 1200 rpm test speed may cause some voltage regulators to deactivate during the test. This may cause a change in the engine load which will make the cylinder test invalid. If the voltage regulator deactivates during the test, stop the test. Run the test again while the voltage regulator is off. When