I am replacing the impeller in my 2000 4.3GL PEFS (4012004849). I have never done this myself so I was surprised to find a very sticky black substance on the end of the bracket that mounts to the block and inserts between the inlet and outlet on the pump. I attached a photo. Does anybody know what this substance is and what it is for? It reminds me of roofing tar. Is this stuff supposed to be there? Or, is something wrong? I didn't see anything wrong with the housing (e.g. cracks).
