coolant bypass??

[81 Gwing]

whats it for?? for when the thermostat is closed so coolant can flow?? can it be blocked off? the 1200 doesnt have it

 

[81 Gwing]

problem solved

 

[dan filipi]

isn't there an extra coolant fitting and hose on the 1200 down at the lower radiator hose fitting?
Maybe that takes the place of the bypass?