[Tongue Pirate]

I just went through the same thing on my "Litte" motor. Pulled the valve covers & did a visual check. It appeared as if one of the rocker studs was leaking at the base. On the small blocks the rocker studs can sometimes run into the water passages. So I borrowed a pressure tester for the cooling system, pumped it up & before I could get to pressure I found the problem. Yup & that wasn't the only rocker stud leaking. I pulled the arms & put a wrench on them. The were hardly tight. The company who installed them for me didn't torqe them correctly. I fixed the problem & let it sit over night at pressure. The next morning I rechecked everything & sewed it back up. Good to go! It may be something minor just like this.