its your wp seals. that is what the weap hole is for (letting you knw they are leaking). its not a big deal to fix, you really only need to buy the 2 seals (i think they are p/n 0760101842). but, go ahead and get the seal support and the 2 orings. they are all cheap parts and you will only need to drain the coolant, remove the cover (get that gasket too just in case), the impeller and the valve train cover. the only other thing you will need is some sealant for the top cover.