Does the water pump impeller fit into a single large hole in the block, or does it have two holes in the front of the block that the pump bolts onto? The correct engine for a 54 truck will have a high mounted pump that aligns the fan with the center of the radiator, a cast iron pulley that is pressed onto the pump shaft, and a fan that bolts directly to the pump without a removable pulley. 2nd.-series 1955 and later engines have a lower mounting position for the pump, a bolt-on pulley, and about 2" or more of shaft between the pump body and the pulley flange. There is an adapter plate available that makes the early style water pump fit the later engine, sold by a member here on the Stovebolt forum.

The fan should not run nearly that close to the radiator- - - -there should be at least 1/2" or more of clearance.
Jerry

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