Oil change + new-pump break-in
Crankcase oil change and break-in procedure for a new or rebuilt recip pump.
This guide is general field reference for trained, qualified service technicians. It is not a substitute for the original equipment manufacturer's service manual, applicable codes (NEC, OSHA, ASME, local), or the judgment of a licensed professional. Procedures, torque values, pressures, refrigerants, and safety requirements vary by make, model, jurisdiction, and revision. Always verify against current OEM documentation and follow your employer's safety program. Working on compressed-air, electrical, pressure-vessel, and refrigerant systems can cause serious injury or death. By using this guide you accept all risk; AirCompDX and its authors disclaim all warranties and are not liable for any damage, injury, loss, or code violation arising from its use.
Hot oil — drain warm but not boiling. LOTO before any guard removal.
- Drain pan
- Funnel
- Lint-free rags
- OEM compressor oil (typ. ISO 100 non-detergent for splash-lube recips; OEM synthetic for screw/continuous-duty)
- 1Drain warm
Run 5 min to warm, shut down, LOTO, drain via crankcase plug into a pan.
- 2Inspect drain debris
Magnetic plug catches steel — bronze flecks or aluminum = bearing or piston wear, escalate to teardown.
- 3Refill
Refill to mid-sight-glass with OEM-spec oil. Overfilling causes foaming and discharge oil carryover.
- 4First-start break-in (new/rebuilt only)
Run unloaded 30 min, then 1 hour at 50% pressure, then full pressure cycling. Change oil again at 50 hours to flush in-bore wear-in particulate.
- 5Log baseline
Record discharge temp, amp draw, and oil level. Use this as the unit baseline for future PM trending.