Ken, Get some of the fluroescent dye used to check A/C systems for leakage (available at most wholesale auto parts outlets). Clean up the top of the engine well. Add the dye to the engine oil and wait to see where it shows up. You'll need a ultraviolet light (can be gotten from most early adolescents
, my grandaughter (9 y.o.) had three of them. Hope this helps..
1987 BMW 325