What is this on my intake manifold?

[jason501]

I am reviving a 1985 chris craft scorpion 186. She has a mercruiser V8 305. I have installed a new long block from rapido engines (cracked block from PO), and installed new exhaust manifolds. However, I don't know what these little ports are on top of the intake manifold are. They emit steam/smoke when engine is running. I have looked at diagrams of replacement parts as well as the service manual in the adult only section but still have no clue. Here are some pictures..

 

[Don S]

Re: What is this on my intake manifold?

That is where a tube covered in insulation came from the intake manifold to the choke coil would have come from. Since you have an electric choke, they are no longer needed. That plate was replaced with a solid plate once the electric choke came along. You obviously have a newer carb on the older manifold.

 

[jason501]

Re: What is this on my intake manifold?

Thanks Don. This was kinda driving me nuts.