Blauparts explains that during an Audi Vw water pump replacement, the key to a factory quality seal is in the preparation of the gasket surface area. Prevent an Audi Vw water pump coolant leak by taking the extra time required. Blauparts video demonstrates the correct Audi Vw water pump replacement technique.
These surfaces should be free of all old gasket material and corrosion build up before installing your new Audi Vw water pump and thermostat. Audi water pump gasket mating surface, the right way.To achieve the optimal just like new surface, it's usually necessary to use a medium grit scotch brite pad and/or angle die grinder with a medium grit scotch brite conditioning pad (see the video). When the water pump mounting surfaces are thoroughly cleaned and smooth, gasket sealing agents are not needed!
Some installers have used sealing compounds which can significantly reduce the sealing function of the Audi Vw water pump gasket. It is important to note that no sealing compounds were used when mating the water pump to the engine block from the factory. The factory Robert Bentley manual makes no reference to using sealing compounds during water pump replacement. It is important to pay attention to and follow the manufacturer's installation instructions. Sealing agents (RTV Form-a-Gasket silicones, aerosol adhesives or sealants) should NOT be used!
Premature leaking from the Audi Vw water pump gasket mating area is almost always due to improper alignment during installation, mating surfaces not being prepared properly, or a sealing agent being used. Sealing agents (RTV Form-a-Gasket silicones, aerosol adhesives or sealants) vary in composition and intended usage. When used in conjunction with composite paper gaskets, they negatively affect the gasket's ability to properly compress and perform the sealing function, rendering them ineffective.
Although uncommon, the wrong type of coolant can eat away at the gasket and eventually cause a leak. Blauparts recommends to always double check all Audi Vw water pump mounting bolts for tightness. A loose or missing water pump or thermostat housing bolt can also result in a leak.