This document outlines the monthly hydraulic system checks and maintenance for various rig components. It includes checking for leaks, changing filters, ensuring proper pressures and fluid levels, inspecting components, and addressing any issues found. The goal is to prevent damage through regular maintenance of the hydraulic systems on the rig.

1. MONTHLY HYDRAULIC SYSTEM CHECKS AND MAINTENANCE
INCLUDES MAIN HPU AND DOGHOUSE, SUBSTRUCTURE AND DRAWWORKS SKID, MAST,
DRAWWORKS AND HPU, TOP DRIVE AND HPU, ST80 AND MUD PUMPS
NOTE: THE CATWALK IS ON A SEPARATE 90 DAY WORK ORDER
MAIN HPU AND DOGHOUSE
NOTE: ALL MAIN HPU PUMPS MUST BE SHUTDOWN AND LOCKED OUT FOR FILTER CHANGES AND
COUPLING CHECKS
1. CHECK THE CONDITION OF DRIVE COUPLING BETWEEN THE MAIN HYDRAULIC PUMP AND DRIVE
MOTOR
2. CHANGE TANK MOUNTED RETURN FILTER ELEMENT – SEE THE FILTER SECTION FOR ELEMENT PART
NUMBERS
3. CHANGE HPU PRESSURE FILTER ELEMENT - SEE THE FILTER SECTION FOR ELEMENT PART NUMBERS
4. CHECK TANK DESICCANT BREATHER(S). REPLACE IF DESICCANT HAS COMPLETELY CHANGED COLOR
FROM BLUE TO PINK.
SEE THE FILTER SECTION FOR BREATHER PART NUMBER
NOTE: ALL TANKS MUST BE EQUIPPED WITH A DESICCANT BREATHER
5. TOP UP THE HYDRAULIC TANK IF NECESSARY TO LEVELS INDICATED ON TANK.
NOTE: THERE IS AN ALARM IN THE DOGHOUSE FOR LOW OIL LEVEL AND A SHUTDOWN FOR LOW,
LOW OIL LEVEL
6. WITH THE MAIN HPU PUMP RUNNING CONFIRM THE PRESSURE IS 2300 TO 2500 PSI.
IF THE PRESSURE IS NOT WITHIN THIS RANGE CONTACT THE MECHANIC FOR ADJUSTMENT.
7. SHUT OFF THE MAIN HPU PUMP AND START THE BACK UP/SKIDDING ENGINE. CONFIRM THE PUMP
PRESSURE IS 500 PSI IN START-UP MODE AND 2300 TO 2500 PSI IN RUNNING MODE.
IF THE PRESSURE IS NOT WITHIN THIS RANGE CONTACT THE MECHANIC FOR ADJUSTMENT.
8. LISTEN FOR ANY HISSING NOISE FROM THE MAIN PUMP MOUNTED RELIEF VALVE. CHECK FOR VERY
HOT RETURN LINE HOSE ON THE RELIEF.
IF EITHER CONDITION EXISTS CONTACT THE MECHANIC IMMEDIATELY FOR ADJUSTMENT.
9. SHUT OFF THE HYDRAULIC COOLER FAN AND USE A PRESSURE WASHER TO CLEAN THE COOLER CORE.
THE PRESSURE WASHER MUST BE SET BELOW 500PSI TO PREVENT DAMAGE TO THE COOLER.

2. 10. CONFIRM THE HYDRAULIC COOLER SWITCH IS SET TO AUTO. THE HAND SETTING IS FOR DIAGNOSTIC
PURPOSES ONLY. CONFIRM THE HYDRAULIC TANK TEMPERATURE IS BELOW 125F. USE THE TANK
MOUNTED THERMOMETER OR HMI SCREEN IN THE DOGHOUSE TO DETERMINE TANK TEMPERATURE.
NOTE: IF THE TEMPERATURE IS ABOVE 125F THEN SOMETHING IS WRONG WITH THE HYDRAULIC
SYSTEM. CONTACT A MECHANIC IMMEDIATELY FOR REPAIRS OR DAMAGE TO THE HYDRAULIC
SYSTEM CAN RESULT FROM OVERHEATING.
11. CONFIRM THE HYDRAULIC COOLING FAN TURNS ON AT 120F AND OFF AT 115F. THIS TEMPERATURE
RANGE CAN VARY BY +-5F.
NOTE: IF THE FAN DOESN’T TURN ON BY 125F CONTACT A MECHANIC IMMEDIATELY FOR REPAIRS OR
DAMAGE TO THE HYDRAULIC SYSTEM CAN RESULT FROM OVERHEATING.
12. CONFIRM THE MAIN HYDRAULIC PUMP SWITCH IS SET TO AUTO. THIS ALLOWS THE PUMP TO BE
TURNED ON/OFF FROM THE DOGHOUSE. THE HAND SETTING IS FOR DIAGNOSTIC PURPOSES ONLY.
13. WITH THE MAIN HPU PUMP RUNNING CHECK FOR LEAKING OR DAMAGED HOSES AND FITTINGS. IF
LEAKS ARE DETECTED TIGHTEN HOSE OR FITTING. DO NOT OVER TIGHTEN. NPT FITTINGS MUST BE
DISASSEMBLED AND RESEALED. ORB FITTINGS MUST HAVE O-RINGS REPLACED. DAMAGED HOSES AND
FITTINGS MUST BE REPLACED.
14. CHECK FOR ANY LEAKING OR DAMAGED HYDRAULIC COMPONENTS. CONTACT MECHANIC OR
HYDRAULIC TECHNICIAN FOR REPLACEMENT PARTS.

3. SUBSTRUCTURE AND DRAWWORKS SKID
1. WITH THE MAIN HPU PUMP RUNNING CHECK FOR LEAKING OR DAMAGED HOSES AND FITTINGS. IF
LEAKS ARE DETECTED TIGHTEN HOSE OR FITTING. DO NOT OVER TIGHTEN. NPT FITTINGS MUST BE
DISASSEMBLED AND RESEALED. ORB FITTINGS MUST HAVE O-RINGS REPLACED. DAMAGED HOSES AND
FITTINGS MUST BE REPLACED.
2. CHECK FOR ANY LEAKING OR DAMAGED HYDRAULIC COMPONENTS. CONTACT MECHANIC OR
HYDRAULIC TECHNICIAN FOR REPLACEMENT PARTS.
3. ENSURE ALL ISOLATION BALL VALVES ON SETUP VALVE BANKS ARE CLOSED. BALL VALVES SHOULD
ONLY BE OPENED DURING RIG SETUP OPERATIONS.

4. MAST
1. WITH THE MAIN HPU PUMP RUNNING CHECK FOR LEAKING OR DAMAGED HOSES AND FITTINGS. IF
LEAKS ARE DETECTED TIGHTEN HOSE OR FITTING. DO NOT OVER TIGHTEN. NPT FITTINGS MUST BE
DISASSEMBLED AND RESEALED. ORB FITTINGS MUST HAVE O-RINGS REPLACED. DAMAGED HOSES AND
FITTINGS MUST BE REPLACED.
2. CHECK FOR ANY LEAKING OR DAMAGED HYDRAULIC COMPONENTS. CONTACT MECHANIC OR
HYDRAULIC TECHNICIAN FOR REPLACEMENT PARTS.
3. ENSURE ALL ISOLATION BALL VALVES ON SETUP VALVE BANKS ARE CLOSED. BALL VALVES SHOULD
ONLY BE OPENED DURING RIG SETUP OPERATIONS.
4. ENSURE THE HEATING LOOP BALL VALVE ON THE MAST VALVE BANK IS CLOSED IN WARM WEATHER
AND ONLY OPEN WHEN THE AMBIENT TEMPERATURE IS BELOW FREEZING.
NOTE: LEAVING THE BALL VALVE OPEN DURING WARM WEATHER CAN OVERHEAT THE VALVE
BANK AND DAMAGE THE SEALS

5. RIGMASTER DRAWWORKS
NOTE: ALL PUMPS MUST BE SHUTDOWN AND LOCKED OUT FOR FILTER CHANGES
1. CHANGE CHAIN OIL SPIN-ON FILTER – SEE THE FILTER SECTION FOR ELEMENT PART NUMBERS
2. VERIFY CORRECT OIL LEVEL IN CHAIN CASE SIGHT GLASS
3. CHANGE PLANETARY OIL SPIN-ON FILTER – SEE THE FILTER SECTION FOR ELEMENT PART NUMBERS
4. VERIFY CORRECT OIL LEVEL IN PLANETARY SIGHT GLASS
5. CHECK CHAIN CASE DESICCANT BREATHER. REPLACE IF DESICCANT HAS COMPLETELY CHANGED
COLOR FROM BLUE TO PINK - SEE THE FILTER SECTION FOR BREATHER PART NUMBERS
NOTE: ALL DRAWWORKS CHAIN CASES MUST BE EQUIPPED WITH A DESICCANT BREATHER
6. WITH THE MAIN HPU PUMP RUNNING CONFIRM THE BRAKE SUPPLY PRESSURE IS 1900 TO 2100 PSI.
IF THE PRESSURE IS NOT WITHIN THIS RANGE CONTACT THE MECHANIC FOR ADJUSTMENT.
7. WITH THE DRAWWORKS BRAKES RELEASED CONFIRM THE BRAKE RELEASE PRESSURE IS 1900 TO 2100
PSI.
IF THE PRESSURE IS NOT WITHIN THIS RANGE CONTACT THE MECHANIC FOR ADJUSTMENT.
8. CHECK FOR LEAKING OR DAMAGED HOSES AND FITTINGS. IF LEAKS ARE DETECTED TIGHTEN HOSE OR
FITTING. DO NOT OVER TIGHTEN. NPT FITTINGS MUST BE DISASSEMBLED AND RESEALED. ORB FITTINGS
MUST HAVE O-RINGS REPLACED. DAMAGED HOSES AND FITTINGS MUST BE REPLACED.
9. CHECK FOR ANY LEAKING OR DAMAGED HYDRAULIC COMPONENTS. CONTACT MECHANIC OR
HYDRAULIC TECHNICIAN FOR REPLACEMENT PARTS.

6. TESCO TOP DRIVE AND HPU
NOTE: TOP DRIVE HPU PUMP MUST BE SHUTDOWN AND LOCKED OUT FOR FILTER CHANGES AND
COUPLING CHECKS
1. CHECK THE CONDITION OF DRIVE COUPLING BETWEEN THE HPU PUMP AND DRIVE MOTOR
2. CHANGE TANK MOUNTED RETURN FILTER ELEMENT – SEE THE FILTER SECTION FOR ELEMENT PART
NUMBERS
3. CHANGE TOP DRIVE GEARBOX FILTER ELEMENT – SEE THE FILTER SECTION FOR ELEMENT PART
NUMBERS
4. CHECK HYDRAULIC TANK DESICCANT BREATHER. REPLACE IF DESICCANT HAS COMPLETELY CHANGED
COLOR FROM BLUE TO PINK
SEE THE FILTER SECTION FOR BREATHER PART NUMBER
NOTE: ALL TANKS MUST BE EQUIPPED WITH A DESICCANT BREATHER
5. TOP UP THE HYDRAULIC TANK IF NECESSARY TO LEVELS INDICATED ON TANK.
NOTE: THERE IS TANK MOUNTED SWITCH THAT SHUTS DOWN THE HPU IN A LOW OIL LEVEL
CONDITION
6. WITH THE HPU PUMP RUNNING AND NO ROBOTICS FUNCTION SELECTED CONFIRM THE PRESSURE IS
50-100 PSI.
IF THE PRESSURE IS NOT WITHIN THIS RANGE CONTACT THE MECHANIC FOR ADJUSTMENT.
7. WITH THE HPU PUMP RUNNING AND ANY ROBOTICS FUNCTION SELECTED CONFIRM THE PRESSURE IS
1900-2100 PSI.
IF THE PRESSURE IS NOT WITHIN THIS RANGE CONTACT THE MECHANIC FOR ADJUSTMENT.
8. WITH THE HPU PUMP RUNNING AND NO ROBOTICS FUNCTION SELECTED CONFIRM THE PRESSURE
SWITCH IS NOT TRIPPED (GREEN LIGHT ON DRILLERS PANEL SHOULD BE OFF).
9. WITH THE HPU PUMP RUNNING AND ANY ROBOTICS FUNCTION SELECTED CONFIRM THE PRESSURE
SWITCH IS TRIPPED (GREEN LIGHT ON DRILLERS PANEL SHOULD BE ON).
10. AFTER THE HPU HAS BEEN RUNNING FOR SEVERAL HOURS CONFIRM THE TANK TEMPERATURE IS
BELOW 130F.
NOTE: IF THE TEMPERATURE IS ABOVE 130F THEN SOMETHING IS WRONG WITH THE HYDRAULIC
SYSTEM. CONTACT A MECHANIC IMMEDIATELY FOR REPAIRS OR DAMAGE TO THE HYDRAULIC
SYSTEM CAN RESULT FROM OVERHEATING.
11. CONFIRM THE TANK HEATER IS OPERATIONAL. USE THE TANK THERMOMETER AND CONFIRM THE
HEATER TURNS OFF WHEN THE OIL TEMPERATURE REACHES THE DIAL SETTING.

7. 12. WITH THE HPU PUMP RUNNING CHECK FOR LEAKING OR DAMAGED HOSES AND FITTINGS. IF LEAKS
ARE DETECTED TIGHTEN HOSE OR FITTING. DO NOT OVER TIGHTEN. NPT FITTINGS MUST BE
DISASSEMBLED AND RESEALED. ORB FITTINGS MUST HAVE O-RINGS REPLACED. DAMAGED HOSES AND
FITTINGS MUST BE REPLACED.
13. CHECK FOR ANY LEAKING OR DAMAGED HYDRAULIC COMPONENTS. CONTACT MECHANIC OR
HYDRAULIC TECHNICIAN FOR REPLACEMENT PARTS.

8. NOV ST80
NOTE: MAIN HPU PUMPS MUST BE SHUTDOWN AND LOCKED OUT FOR FILTER CHANGE
1. CHANGE THE SUPPLY PRESSURE FILTER ELEMENT - SEE THE FILTER SECTION FOR ELEMENT PART
NUMBERS
2. WITH THE HPU PUMP RUNNING CHECK FOR LEAKING OR DAMAGED HOSES AND FITTINGS. IF LEAKS
ARE DETECTED TIGHTEN HOSE OR FITTING. DO NOT OVER TIGHTEN. NPT FITTINGS MUST BE
DISASSEMBLED AND RESEALED. ORB FITTINGS MUST HAVE O-RINGS REPLACED. DAMAGED HOSES AND
FITTINGS MUST BE REPLACED.
3. CHECK FOR ANY LEAKING OR DAMAGED HYDRAULIC COMPONENTS. CONTACT MECHANIC OR
HYDRAULIC TECHNICIAN FOR REPLACEMENT PARTS.

9. MUD PUMPS
NOTE: MUD PUMP LUBE PUMPS MUST BE SHUTDOWN AND LOCKED OUT FOR FILTER CHANGES AND
COUPLING CHECKS
1. CHECK THE CONDITION OF DRIVE COUPLING BETWEEN THE LUBE PUMPS AND DRIVE MOTORS
2. CHANGE SPIN-ON LUBE FILTER – SEE THE FILTER SECTION FOR ELEMENT PART NUMBERS
3. CHECK MUD PUMP POWER END CASE DESICCANT BREATHER(S). REPLACE IF DESICCANT HAS
COMPLETELY CHANGED COLOR FROM BLUE TO PINK - SEE THE FILTER SECTION FOR BREATHER PART
NUMBERS
NOTE: ALL MUD PUMPS MUST BE EQUIPPED WITH A DESICCANT BREATHER
4. TOP UP THE MUD PUMP CASE IF NECESSARY TO LEVELS INDICATED ON DIP STICK OR SIGHT GLASS.
5. WITH THE LUBE PUMP RUNNING CONFIRM THE PRESSURE IS 50-100 PSI.
IF THE PRESSURE IS NOT WITHIN THIS RANGE CONTACT THE MECHANIC FOR ADJUSTMENT.
6. WITH THE MUD PUMP RUNNING CONFIRM THE PRESSURE FROM THE INTERNAL LUBE PUMP IS 5-10
PSI.
7. WITH THE LUBE PUMP RUNNING CHECK FOR LEAKING OR DAMAGED HOSES AND FITTINGS. IF LEAKS
ARE DETECTED TIGHTEN HOSE OR FITTING. DO NOT OVER TIGHTEN. NPT FITTINGS MUST BE
DISASSEMBLED AND RESEALED. ORB FITTINGS MUST HAVE O-RINGS REPLACED. DAMAGED HOSES AND
FITTINGS MUST BE REPLACED.
8. CHECK FOR ANY LEAKING OR DAMAGED HYDRAULIC COMPONENTS. CONTACT MECHANIC OR
HYDRAULIC TECHNICIAN FOR REPLACEMENT PARTS.