Portable compressor maintenance checklist.

Don't treat portable compressor service as a once-a-year requirement

We probably all know that maintenance is the key to equipment longevity. For an equipment rental house or contractor, keeping up with compressor maintenance keeps equipment ready to rent and ready to work.
The primary guide for maintenance on equipment in your fleet should always be the service manual for each piece of equipment. However, you can use this checklist as a guide for regular maintenance to keep your machine running smoothly and efficiently.
Compressors can be divided into six sub-assemblies, and must be checked and maintained on a regular basis.

1. Pump or airend — the unit’s compression mechanism

Rotary screw airend — compresses air internally using two helical lobe rotors inside a housing.

  • Check for mechanical seal leakage
  • Recommended rebuild: 50,000 to 100,000 hours
  • Check for inlet valve wear
  • Check for excessive bearing “play”

2. Engine - the internal combustion engine provides the energy to turn the airend that compresses the air

  • Check engine lubricant level
  • Adjust valve clearance
  • Check air intake filter contamination alarm
  • Clean and replace air intake filter regularly
  • Check and adjust engine fan belt tension
  • Inspect the fuel injectors
  • Change engine lubricant at 500 hours
  • Change engine lubricant filter at 500 hours

3. Chassis - the frame and housing for compressor components

  • Check tire pressure and inspect for excessive tread wear
  • Tighten wheel bolts if necessary
  • Grease coupling head, joints, and tow bar

4. Lubricants - lubricants in the airend cool, seal, lubricate, and remove contaminants.

  • Use proper grade (see manufacturer's manual)

  • Use synthetic lubricant for maximum service life

  • Drain existing lubricant before refilling

  • Draw lubricant samples at regular intervals to determine maximum lubricant life

5. Compressor filters

Mobilair filters

The compressor air filter is generally located prior to the airend inlet valve, remove bulk contaminants from the air entering the airend.

  • Use proper micron rating as specified by OEM
  • Check pressure differential and if necessary carefully clean according to manufacturer's recommendations
  • Check for worn/damaged seals
  • Check structural integrity
  • Change air filter at 500 hours

Compressor lubricant filter and lubricant separator.

The compressor lubricant separator removes particulates from the lubricant circulated in the airend. The lubricant separator removes lubricant from the air before it is discharged.

  • Check lubricant level and change regularly
  • Clean the lubricant cooler
  • Replace compressor lubricant filter
  • Change the lubricant separator cartridge in the lubricant separator
  • Use only genuine replacement parts
  • Change lubricant at 1000 hours
  • Change compressor lubricant filter at 1000 hours
  • Change lubricant separator cartridge at 2 years of 1000 hours
Caution: do not change filters or check fluids while the compressor is running. Spraying liquids such as oil can cause burns or serious injury.

6. Cooler

Compressed air treatment

Provides cooling for the engine and in some cases will provide compressor fluid cooling.

  • Check the engine coolant level
  • Inspect hoses and hose clamps for wear
  • Check for visible contamination and clean regularly
  • Check the anti-freeze protection and clean regularly

Other components

  • Check the battery's electrolyte and pole connections
  • Check the lifting frame
  • Check hoses for wear and tightness
  • Check all accessible screw connections, pipelines, and clamps for wear and tightness
  • Grease the canopy hinges
  • Ensure that pressure and temperature gauges are working

Additional resources