Air Compressor: Won't build tank pressure
Shut the drain valve at the bottom of the tank if it's open. Check for air tank leaks. Replace the tank if it's leaking. Tighten loose air tube fittings on the tank, check valve and pressure switch to prevent air leaks. Rebuild the pump if it won't compress air.
These repairs may help solve your Air Compressor problem:
Rebuild the air compressor pump
Worn pump parts and seals prevent the pump from compressing air. If the pump won't compress air, rebuild the pump with new parts and seals.
Replace the air compressor valve plate
The valve plate regulates airflow into and out of the pump cylinder to compress air. Replace the valve plate if damaged.
Tighten air compressor air tube fittings
Inspect air tube fittings regularly. Firmly tighten any leaking air tube fittings.
Replace the air compressor safety valve
The safety valve pops open to relieve excessive air pressure if the pressure switch fails to shut off the air compressor at the cut-out pressure setting. Replace the safety valve if it leaks or pops open at normal operating pressure.
Replace the air compressor tank
Don't try to fix a leaking air compressor tank. Replace the tank if it leaks air.
Replace the air compressor air tubes
Air tubes carry compressed air from the pump to the tank and from the tank to the outlet supply fitting. Replace air tubes if damaged or leaking.