a month ago I bought a promax recovery machine from a seller on ebay. everything was fine until i notice that refrigerant was leaking from the inlet and outlet when the valves were in the close position. instead of returning the item to the seller for a refund, i decided to fix it by replacing the whole manifold. I had no problem removing the old manifold and installing the new manifold. I pressure tested with air to 400 psig the first time and the second time to 500 psig the second time. both times the pressure swithes shut off the recovery machine like thay were designed to do. later i pressure tested to 100psig with r11. however, the leaking problem continued from the inlet and outlet. i replaced the whole manifold, butthe inlet and outlet leaks out refrigerant when the valves are close. my question is: did i damage the manifold when i installed the inlet and outlet to the manifold by over tighting. or was it the pressure test. can this problem be fix without buying a new manifold. plaese help.