The unit works but has a leak at a check valve location.
An internet search provides this information.

The Industrial Air IV5018023 is a heavy-duty, stationary, two-stage vertical air compressor. It features a two-stage oil-bath cast iron pump designed to deliver up to 175 maximum PSI. This model is built for automotive shops, commercial garages, and industrial applications that require constant, high-volume air supply to run multiple pneumatic tools simultaneously.
Core Technical Specifications
Pump Design: Two-stage, inline cast iron pump with an oil-bath lubrication system.
Maximum Pressure: 175 PSI.
Tank Configuration: 80-gallon stationary vertical steel tank (certified by ASME).Power Source: 230V Single-Phase electric setup.
Essential Replacement Parts & Maintenance
If you are maintaining or rebuilding this specific pump model, individual components and complete rebuild kits are available through specialized retailers like Master Tool Repair:SC23 Air Compressor Pump Overhaul Kit: Includes low-pressure and high-pressure intake/exhaust valves, an oil seal, a complete gasket set, and bearing inserts.
Piston Ring Sets: Individual sets are separated by the high-pressure (smaller) and low-pressure (larger) pistons.
Centrifugal Unloader Valve: Replace this specific assembly if your unit exhibits air leaks from the unloader while the compressor is running.
Air Filter Assembly Kit: A 1" MPT metal filter assembly used to swap out older square housing styles for a high-flow round design.