Husqvarna S427 Operation Manual - Page 19

Changing Hydraulic Oil and Filter NOTE: Change the hydraulic oil and oil filter every season or 100 hours. 1. Clean area around hydraulic supply hose. 2. Place container under oil filter and hydraulic supply hose to catch oil. 3. Remove hose clamp and disconnect hose from hydraulic tank. Hydraulic System Purge 1. With the engine running, extend the hydraulic cylinder out fully and then retract fully. 2. Repeat four to five times. Erratic movement in the hydraulic cylinder indicates that there is air in the system. 3. Stop the engine and check the hydraulic oil level. Add if necessary. 4. Repeat extending and retracting of hydraulic cylinder unit motion is consistent and smooth in both directions. 5. Ensure the hydraulic oil is at proper level. Hydraulic Supply Hose Hydraulic Tank IMPORTANT At this point a large amount of hydraulic oil has been drawn into the hydraulic cylinder and hoses. Be sure to refill the oil reservoir to prevent pump damage. 4. Remove oil filter. 5. Allow tank to drain. 6. Reinstall hydraulic suction hose and tighten hose clamp. 7. Lubricate rubber gasket on new oil filter with clean hydraulic oil. 8. Spin new oil filter onto filter housing until it makes contact. Tighten oil filter another half turn. 9. Add new oil to the oil tank. 10. Check hydraulic oil level. 11. Properly dispose of waste oil. - 19 -