Open tank ball valve.
Fill tank with material.
Verify no obstruction in the tank.
Prime the machine until the air is removed.
Remove; clean or replace check valve.
Remove and replace piston if worn.
Reconnect input air line to machine. Increase air pressure regulator adjustment.
Replace static mixer. Incorporate purge timer or decrease purge timer delay to prevent mixer blockage.
Readjust the ODV setting to occur sooner.
Remove check valve; clean and replace.
Replace actuator/servo motor.
Readjust air pressure regulator to value used when machine was calibrated, or recalibrate machine.
Check tank levels; fill and prime as necessary.
Replace static mixer. Prime machine.
Remove check valve ; clean or replace as necessary.