First of all 1994 civic with b7 block z6 head. Car doesn't leak any fluids. Other day I was driving and noticed it idleing low and rough, not smoking out of exhaust nor smelling like coolant out of exhaust. Then I noticed an oil spot under the car and oil was leaking out of the coolant reservoir and checked my radiator and was oily and brownish like color. Checked the oil and was the normal color not milky at all. Car didn't overheat at all. Ive heard of some Honda motors having a crack in it and people ending up buying a new shortblock because of a hairline crack in the bottom end resulting in this. Ive heard of accords having this problem but haven't had much luck with finding any older issues with the D series motors. Car already has a metal headgasket. Would yall lean more toward the headgasket or possible cracked block or the head, or am I just better off dissasembing it and testing everything? Thanks

 

Compression test the cylinders.

 

had oil in my cooling system, my water hoses blew 3 times in a month.
appeared to be blown head gasket
during leak down test removed radiator cap, bubbles come from the coolant
head resurfacing and new head gasket solved the problem for me.
forget to mention its d16y8 motor.