Reply To: Evinrude 4423, water pump

[tjlumpkin]

David, I am also restoring a 4423.   The two parts pictured are indeed supposed to be riveted together forming a space between the two.  This is a two stage centrifugal pump.  The lower impeller output flow goes between these pieces, directing flow to the inner diameter of the upper impeller (your first picture).   FYI,  I’m manufacturing replacement impellers and currently in the testing phase.   Once reliability and durability are proven,  I’ll make them available to 4423 owners.