Anyone repair the Carrier centrifugal chiller. He should be know a shim pack under the impeller. This shim pack have many pcs. of aluminium sheet (0.0002" per pc.). It is very easy to remove from the shim pack to let you very easy to adjust the thickness of it. Who know the correct name of this shim style? I want to find this style shim to repair the water pump, because it is very easy to adjust the thickness!