Common Problems with Reciprocating Compressors—and How to Fix Them
Reciprocating (piston-style) compressors are tough, dependable, and built to last, but they’re not immune to wear and tear. When something goes wrong, it’s usually tied to a handful of repeat issues.
The good news? Most problems are fixable, and many are avoidable with the right maintenance plan and the right parts.
1. Loss of Pressure or Low Air Output
If your compressor isn't building pressure like it used to, it could be due to worn piston rings, leaking valves, or a failing head gasket.
Fix: Check for air leaks first. If the system is sealed, it may be time for a gasket kit, valve replacement, or piston ring kit.
2. Overheating
Recip compressors naturally run hot, but excessive heat shortens lifespan. Poor ventilation, dirty intercoolers, or running beyond the duty cycle are often to blame.
Fix: Improve airflow around the unit, clean cooling fins, and make sure the compressor isn’t oversized for the workload. Don’t skip routine oil and filter changes, either.
3. Oil in the Air Lines
If you’re seeing oil downstream, your piston rings may be worn or oil levels may be too high. Left unchecked, this can foul downstream equipment or contaminate the final product.
Fix: Replace worn rings or seals using a step saver kit, and verify oil levels per the manual.
4. Knocking or Rattling Noises
Unusual sounds could point to loose connecting rods, worn crankshaft bearings, or piston slap. This isn’t a “wait and see” situation. It only gets worse with time.
Fix: Shut it down and inspect connecting rod assemblies and internal bearings. Use OEM-equivalent rebuild kits to restore performance.
5. Dirty or Clogged Air Filters
Restricted intake airflow leads to lower output, hotter operating temps, and unnecessary strain on the machine.
Fix: Replace filters regularly. Especially in dusty shops or jobsite conditions. Find your replacement in our air filter collection.
Maintenance Makes All the Difference
Most problems with piston compressors can be prevented by staying on top of routine service. Here's what we recommend for air-cooled recips:
- Oil changes: Once a year
- Oil filters: Every 3–6 months
- Air filters: Every 3–6 months
- Piston rings, gaskets, valves: Inspect annually
Want to simplify this even more? Use the ACS mobile app (also on Google Play) to track your compressor’s service history and reorder parts in seconds.