Service and Repair Manual October 2019Manifolds66 S® -80 XC ™ • S® -85 XC ™ • S®-80 HF • S®-85 HF Part No. 1280490GT8-2 Valve Adjus tments - F unc tion M anifol d8-2 Valve Adjustments -Function ManifoldHow to Adj ust the Sy stem Reli ef ValveHow to Adjust the System ReliefValveNote: Perform this procedure with the boom in thestowed position.Note: Refer to Function Manifold Component list tolocate the system relief valve.Note: Auxiliary power will be used to perform thisprocedure. Do not start the engine.1 Connect a 0 to 5000 psi / 0 to 350 barpressure gauge to the diagnostic nipple (ptest)located next to the auxiliary pump.2 Simultaneously activate and hold the auxiliarypower button and the primary boom retractbutton with the primary boom fully retracted.Observe the pressure reading on the pressuregauge. Refer to Specifications, HydraulicSpecifications.3 Locate the system relief valve on the functionmanifold. Use a wrench to hold the relief valveand remove the cap.4 Adjust the internal hex socket. Turn itclockwise to increase the pressure orcounterclockwise to decrease the pressure.Install the relief valve cap.Tip-over hazard. Do not adjustthe relief valve higher thanspecified.5 Repeat step 2 to confirm relief valve pressure.6 Remove the pressure gauge.How to Adj ust the Boom Dow n R elief Valv eHow to Adjust the Boom DownRelief ValveNote: Perform this procedure with the boom in thestowed position.Note: Refer to Function Manifold Component list tolocate the boom down relief valve.Note: Auxiliary power will be used to perform thisprocedure. Do not start the engine.1 Connect a 0 to 5000 psi / 0 to 350 barpressure gauge to the diagnostic nipplelocated next to the auxiliary pump.2 Simultaneously activate and hold the auxiliarypower button and the primary boom downbutton with the boom fully lowered. Observethe pressure reading on the pressure gauge.Refer to Specifications, HydraulicSpecifications.3 Use a wrench to hold the relief valve andremove the cap on the function manifold.4 Adjust the internal hex socket. Turn itclockwise to increase the pressure orcounterclockwise to decrease the pressure.Install the relief valve cap.Tip-over hazard. Do not adjustthe relief valve higher thanspecified.5 Repeat step 2 to confirm relief valve pressure.6 Remove the pressure gauge.
