I removed the inspection cover when I was installing anew starter and noticed some of the green coolant in the bottom of the cover, not much, just a little. I just bought the car and it needed the starter so I never started it. It starts and runs fine, drives pretty smooth for an old 305. The coolant looks like its dripping from the top of the block somewhere cant really tell. I'm guessing its the freeze plugs on the back of the motor? It's not entering the oil so no internal leaks, which is good.

Brian

 

It could be the rear freeze plugs. I've never seen them leak, though (crud is more likely to settle on and corrode the side plugs).

More likely you've got an intake manifold leak. Best way to find out is to get it cleaned, running, and watch where it comes from.

 

Never seem 'em leak either but... It wasnt bad but I degreased the engine yesterday so I'm gonna drive it a few times to work and see if it gets worse and where its comming from.