I would start with looking at/reviewing the owner/operator manual for service and maintenance information if available rather than trying to find something generic.

Regards,

Here's a precis' of the PM intsruction mounted on ours:

1. Check E-stop for functionality.  LO/TO here.
2. Blow radiator fins and coils free of debris.
3. Remove and inspect filter. Re-oil and replace, or install new, properly oiled filter.
4. Check unit oil.  Drain completely if in excess of specified hours, and replace or top-off level in tank to specified level.
5. Bleed main compressed air tank free of pressure and moisture.  Collect water sample for analysis, if desired.
6. Turn unit on, run for 20 minutes, monitor air temperature coming out of tank.  
7. Check relief valves for operability.
8. Check pressure cut-off/cut-in switch against unit PSI gauge for correctness.
9. Visually check all fittings for observable pinhole leaks or looseness.
10. Record runtime hours, wipe down main control panel and gauge cluster, and return machine to normal operation.