TENSIONER AS 5071870 - Caterpillar

The valve that is used to manually lower the loader is located under the machine on the right side of the machine.
Slowly turn the valve counterclockwise until the loader is lowered to the ground.
After the loader has been lowered to the ground, turn the valve clockwise until the valve stops.
Make the necessary repairs before you operate the machine.If no electrical power is available, or a break in a hydraulic line has occurred, perform the following steps in order to lower the lift arms to the ground.
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The load control valve for the loader is located on each lift cylinder.
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Install a 6 mm (0.25 inch) hose onto the purging screw. Route the other end of the hose into a suitable container in order to drain the oil.
Loosen the purging screw slightly and allow the oil to drain until the loader lowers to the ground. Tighten the purging screw after the loader is on the ground.Lowering the Boom
Personal injury or death can result from the boom falling.Keep personnel away from the rear of the machine when lowering the boom.
Lowering the Boom with Electrical Power
If there is a loss of hydraulic power, and the machine meets the following conditions, perform the following procedure to lower the boom to the ground.
Electrical power is available.
There is not a break in a hydraulic line.
Place the hydraulic lockout switch in the UNLOCK position.
Turn the engine start switch key to the ON position and crank for five seconds.
Leave the key in the ON position.
Slowly tap the joystick control for the boom into the DOWN position in order to lower the boom to the ground.Lowering the Boom without Electrical Power
If there is not electrical power and there is not a break in a hydraulic line, perform the following procedure to lower the boom to the ground.
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Boom Lock Valve
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Remove the tamperproof cap on the boom lock valve.
Loosen the locknut. Turn the screw clockwise. The screw should be fully seated.
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Remove the floorplate in order to gain access to the boom control valve.Note: Keep personnel away from the rear of the machine.
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Loosen the nut that locks down the stem. Slowly turn the stem of the relief valve in a counterclockwise direction. The boom will lower to the ground.Note: The boom valve will be the second valve on machines that are equipped with a six bank valve.
Slowly turn the stem of the relief valve in a clockwise direction. Rotate the stem until the stem bottoms out in the hole. Tighten the nut in order to lock down the stem. This procedure will change the setting for the relief valve. Contact your Caterpillar dealer for the proper relief valve setting.
Make the necessary repairs before you operate the machine.Lowering the Boom with a Hydraulic Component Failure
If a hydraulic component has failed, perform the following procedure to lower the boom to the ground.
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Boom Lock Valve
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Remove the tamperproof cap on the boom lock valve.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance,