Abstract: A water pump for an internal combustion engine is provided comprising a pump holder and a pump block. The pump block includes a pump mount having a shaft passing therethrough terminating in an impeller. The pump block is mounted to the holder via a quick release, bayonet type coupling with the pump mounted sealed to the holder. A snap fitting locking ring locks the block to the holder and prevents disconnecting the coupling by blocking reverse rotation of the block relative to said holder.

Abstract: The invention proposes apparatus for testing plastic profiles or sections, particularly extruded polyethylene tubes which have been cross-linked by radiation, although the application of the invention is not restricted to that field. An electrode at a high potential and a grounded electrode are provided and surround the moving plastic section. A probe consisting preferably of a metal braid is disposed inside the profile or section adjacent to the apparatus and is preferably magnetically held and is not directly conductively grounded to the outside. Defects such as electron punctures in the wall of the plastic profile or section are detected by the breakdowns which are effected at the locations of said defects. It will be understood that the apparatus proposed by the invention can also be used to detect the location of other defects, such as contraction holes, inclusions, bubbles etc., and to deliver control signals to suitable devices for marking, rejecting etc.