the arrow follows coolant flow.




2 is the front heater core, 3 is the engine and 4 is the thermostat

 

what is 5 and 6 then if you dont mind

 

1 = heater core, rear
2 = heater core, front
3 = engine
4 = thermostat
5 = engine oil cooler (optional equipment)
6 = water pump
7 = radiator
8 = coolant recovery bottle
9 = coolant flow, pressure cap vacuum
10= coolant flow, pressure cap relief

 

Just another confirmation...arrow points down.

What is the point of this valve?

Bless you guys for this forum!

-Sten

 

Think of a merge lane on an interstate.

If the constrictor isn't there, the water cannot circulate from the rear heater core into the main line. The constriction in the valve speeds up the coolant allowing it to leave/enter the main line. Without it you would get little to any hot water to the rear heater core.