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Installation
HC-10 NEXSTAR
System Relief Valve Setting Instructions
When utilizing outrigger control valves provided by Auto Crane
:
Auto Crane hydraulic powered outriggers utilize a control valve which contains an integral hydraulic relief
valve that is preset at the factory. This preset is NOT the final setting and MUST be adjusted to account
for hydraulic system backpressure once the installation is complete. The adjustment is straight forward
and requires basic hand tools, a thermometer or other means to measure hydraulic oil temperature, a
hydraulic pressure gauge with a minimum rating of 5,000 PSI, and hydraulic fittings necessary to install
the gauge in-line with the incoming pressure line to the outrigger control valve body.
To make final adjustments to the outrigger relief valve:
1. The outrigger hydraulic relief valve contains should be adjusted 200 PSI above the crane hydraulic
relief valve. Refer to the General Specifications section for the crane pressure requirement.
2. Install the hydraulic pressure gauge in-line with the incoming pressure line to the outrigger control
valve body.
3. With all personnel clear of the vehicle, start the engine and engage the vehicle PTO. Let the hydraulic
oil warm until it reaches 100
°
F.
4. While watching the hydraulic pressure gauge, activate a hydraulic outrigger function to deadhead the
hydraulic system. Read the gauge value quickly and do not hold the function in the deadhead position.
5.
Using the hand tools, back off the lock nut on the hydraulic relief valve and make small rotation
adjustments (1/2 turn) to the relief valve stem.
6. Repeat the Step 4 to check if this adjustment meets the system requirements. If not, then repeat Step
5 and Step 4 until correct.
7. Tighten the lock nut on the hydraulic relief valve.
8.
Remove the hydraulic pressure gauge and fittings and re-attach the pressure supply line to the
hydraulic valve body.
When not utilizing outrigger control valves provided by Auto Crane
:
Ensure that the relief valve used is set to between 50-200 PSI higher than the crane pressure
requirements. Reference the General Specifications section for crane flow and pressure requirements.
Under no circumstances should this relief valve setting exceed any of the hydraulic system component’s
ratings or limitations as component damage or personal injury may result.