Author Topic: radiator system question  (Read 3843 times)

Offline sbx22

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radiator system question
« on: February 05, 2012, 09:56:13 PM »
I have a question re: my truck's radiator system. I have seen cars/trucks with a sealed vs. vented radiator system. Sealed meaning there is no way for excess radiator fluid to spill out. Vented meaning if there is too much fluid, there is an escape route for the excess fluid. Do our trucks operate with one of these and which one? What are the pros and cons? The way it's set up right now, my "catch can" or reservoir has a valve that I can open up to "vent" the cooling system or keep it closed to "seal" it. ie. We had a Dodge Caravan that was "vented", my other car an Acura Legend has a "sealed" system. Thanks.

Offline audrima

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radiator system question
« Reply #1 on: February 06, 2012, 12:00:49 AM »
My 78 c25 has a hose right below the rad cap that goes to a plastic can with a line that side something like full cold o0 it's all org too.

Offline Irish_Alley

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Re: radiator system question
« Reply #2 on: February 06, 2012, 01:34:29 AM »
As far as I know all systems are sealed with a overflow tank. This is a safety system so the coolant will not boil and if it does overheat it will release into the overflow tank. Now some tanks sit as high as the radiator so the fluid will flow back into the radiator. While other will just catch the overflow so it doesn't spill onto the ground. If you keep antifreeze +Psi it will increase the boiling point at which it boils but if it overheats, the cap acts like a pressure release and will open much like the thermostat in the intake
« Last Edit: February 07, 2012, 10:18:23 AM by Irish_Alley »
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Offline ehjorten

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Re: radiator system question
« Reply #3 on: February 06, 2012, 09:16:53 AM »
A 'sealed' system is a more modern system.  The system is designed to keep the radiator itself completely full, without air in it.  Older styles where you simply had an overflow system that would not allow excess coolant to be sucked back into the radiator had the top couple of inches of the radiator exposed to air and allowing for expansion increased the rate of corrosion inside the radiator.  An expansion tank is the best way to go!  Any radiator can be converted to have an expansion tank.  You need to have the proper radiator cap that will allow coolant to be drawn back into the radiator when it cools, and you need to have the tube between the radiator and expansion tank submerged in coolant so that it can draw the excess coolant back into the radiator.  The expansion tank needs to be vented so that it is not pressurized and can allow the coolant to flow back and forth.
-Erik-
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Offline sbx22

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Re: radiator system question
« Reply #4 on: February 06, 2012, 06:01:10 PM »
A 'sealed' system is a more modern system.  The system is designed to keep the radiator itself completely full, without air in it.  Older styles where you simply had an overflow system that would not allow excess coolant to be sucked back into the radiator had the top couple of inches of the radiator exposed to air and allowing for expansion increased the rate of corrosion inside the radiator.  An expansion tank is the best way to go!  Any radiator can be converted to have an expansion tank.  You need to have the proper radiator cap that will allow coolant to be drawn back into the radiator when it cools, and you need to have the tube between the radiator and expansion tank submerged in coolant so that it can draw the excess coolant back into the radiator.  The expansion tank needs to be vented so that it is not pressurized and can allow the coolant to flow back and forth.

This last sentence, my friend, was what I wanted confirmed. I know I didn't make sense on my first post, I meant vented vs. sealed at the coolant reservoir, not the radiator itself. I feel dumb. Cool, I'll try this out.