with the GUNK in the lifter valley this is why I say no to dino oil in these engines with the use of alcohol fuels !
with the marvel mystery oil this will reduce this build up. if you continue to use non synthetic then this gunk will grow again and cause engine noise/dirty lifters.
you need a shop to pressure test your coolant system.. use of leak detector dye to find leaks..
could be the water pump leak is at the WEEP hole or at the engine water pump gaskets... try to re-torque the water pump bolts.