Coolant flow direction

[khardrunner14]

This may be kind of an odd question, but bear with me as I'm new to the duratech.

The bottom hose running from the block to the radiator on my truck is constantly cold, even when the thermostat is open, while the top hose is hot. Normally, I would expect the opposite as the coolant should flow from the top of the radiator, through the block and back to the bottom of the radiator. Is the flow reversed in this motor or do I need a new thermostat?

 

[Jorley]

As far as I know the flow is from top to bottom on any radiator. This allows the hot water to enter the top and flow down thru the radiator to be cooled, then back to the engine. Atleast that is the way it works on my Bll. Run the engine with the radiator cap off and see which way the fluid is running.

One other thing, if the flow was from the bottom to the top, if the radiator was low on coolant,there would be nothing but air in the top so the water pump would have no water to pump. With the flow from top to bottom, there will always be water in the lower hose.

 

[Wicked_Sludge]

i dont think ive ever seen a vehicle that pulled coolant from the top hose and pushed it from the bottom. the top hose is always the "hot" hose.

besides the issue of not being able to pull the coolant from the top of the radiator (gravity and all), heat rises....so it only makes sense to get your "cold" coolant from the bottom of the radiator.