1977 Merc 175 HP serial 4733877 - Cooling system relief valve. I have a "design I" Poppet Valve. The popper valve contacts the rubber grommet (in the recessed hole in the block) slightly before the plate/cover contacts the block, so when I tighten the plate/cover bolts there is some "spring tension" which seems to unseat the diaphragm slightly. Is this normal? Also, is it normal for the poppet cover vent hole to spit water?