Vacuum Check Valve: Testing and Inspection

1. Remove check valve from vacuum hoses.
2. Connect a vacuum gauge to EFE side of check valve and connect a vacuum pump to other side of valve, then apply vacuum.
3. The vacuum gauge should show a reading and hold that reading. If not, replace check valve. A slow leak-down indicates the check valve is defective. If leak-down is fast, check to see if valve is backwards.