Circulation of water cooled intake?

[Mr_Mudney 2]

Question about the routing of coolant through the intake manifold on my 1979 620 l20b. There’s the ports on either side of the intake to take water in from the head, but there’s another line that connects to the thermostat housing, and then wraps around the engine and connects to something over there. The auxiliary coolant line just confuses me, what’s it’s purpose? 

[bilzbobaggins 832]

Its the coolant bypass.  It gets water past the thermostat for faster warmups and to prevent a cold pocket of water on the thermostat.

[Mr_Mudney 2]

Okay thanks a lot!