I believe the hose on the intake manifold is the SUPPLY TO the heater core and the hose to the water pump is the RETURN FROM the heater core. The supply furnishes the hot water to the heater and the return allows the cooler water to come back to the water pump to be recirculated back to the engine.Quick question on a 318 poly's heater hose routing - Does the hose on the water pump go to the heater and the hose on the intake come from the heater? Thanks.
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