My current radiator (unknown origin, but keeps the truck cool) has a pressurized cap which keeps it air tight. The overflow tube is also sealed off because the cap seals on the below the opening for the tube. I would like to put an aftermarket overflow bottle in and remove the pressurized cap and place a standard cap on it which would allow the coolant to pass to and from the resevoir bottle. Is this okay to do or does the radiator need the X lbs pounds of pressure to circulate the coolant through the system? Thanks,

Mike

'65 289 and automatic. Didn't know if this would be needed or not.

 

i don't think that would be a problem. i suggest you check with who ever you are buy the system from.
good luck?
let us know what you do and how it works out.

 

I bought it from the a local parts shop. The fellas and ladies down there are always helpful and their intentions are good, but on occassions I have received mixed advice from them. I was hoping someone here had tried it or had a better understanding of how a cooling system worked.

Mike

 

hol, what is your objective in changing to the other method.

John

66 F100s
In the still cool hours of the night, you can hear chevys rusting away.

 

Unless I missed something here You should use a presureized cap and the overflow bottle!
The preasure cap raises the presure in the system to keep the water from boiling in isolated sections of the cooling system, like head pasages, till it gets to the radiator for cooling. Boiling water turns to gas vapor and will not transfer heat from `hot` spots. Now, as the water is expanding the presure will go UP and the expanding water will be contained in the overflow bottle. As the water cools back down,when not running , and the water `shrinks back` in the system the presure cap will allow water to be `recovered` from the side expansion tank and go to the radiator.

You do not need presure to circulate water in the system. the water will circulate as the water pump turns.

In a closed system air will compress. Fluid will not. you have to allow for thermal expansion.
__JOHN__Õ¿ö
72 F-250
ICQ#6030753
http://clubs.excite.com/comm/area/pw/welcome/main.asp?cid=188005&auth=

 

I just wanted to be able to pop the hood and check the bottle before, during, after running the truck to insure there was coolant. I have little knowledge of the engine's history and the guy I bought if from only had it several months. I have dropped in several gauges to help me monitor the engine so I could possibly correct a problem before the engine had the opportunity to would go south. I just thought this might be another indicator to check during the different stages of running the truck (cold, running, afterwards). I might be totally wrong in my theory, but it was just a thought.

Thanks,

Mike

 

The cap that is on there right now seats to the bottom of the filler neck and once the red pressure release lever is locked down it completely seals off the opening for the overflow tube. I would assume if the pressure was to great it would force the seal up and release it through the tube. I just wasn't sure if I would have to change to a cap that would allow the fluid to run undisturbed to the aftermarket resevoir. I have a manual that covers the '65-? Fairlanes (the 289 I have came from this model). It stated the '65s had both systems (with and without the bottle), but didn't go into specifics as far as the cap requirements or operation for each set up. The radiator I have came with the truck, but is definitley not the original from the truck or the Fairlane. Sorry for my ignorance. Thanks for your help.

Mike

 

>Unless I missed something here
> You should use
>a presureized cap and the
>overflow bottle!
>The preasure cap raises the presure
>in the system to keep
>the water from boiling in
>isolated sections of the cooling
>system, like head pasages, till
>it gets to the radiator
>for cooling. Boiling water turns
>to gas vapor and will
>not transfer heat from `hot`
>spots. Now, as the water
>is expanding the presure will
>go UP and the expanding
>water will be contained in
>the overflow bottle. As the
>water cools back down,when not
>running , and the water
>`shrinks back` in the system
>the presure cap will allow
>water to be `recovered` from
>the side expansion tank and
>go to the radiator.
>
>You do not need presure to
>circulate water in the system.
>the water will circulate as
>the water pump turns.
>
>In a closed system air will
>compress. Fluid will not. you
>have to allow for thermal
>expansion.
>__JOHN__Õ¿ö
>72 F-250
>ICQ#6030753
>http://clubs.excite.com/comm/area/pw/welcome/main.asp?cid=188005&auth=

This is correct. Even if you have an overflow bottle you still need the pressurized cap. Run the overflow tube into the bottle. When the engine gets hot enough and the pressure rating of the cap is exceeded the fluid will go into the bottle instead of the ground and as it cools it will get sucked back into the sealed system. Make sure you put some antifreeze/water in bottle to start with and make a mark at the full hot and full cold points so you can keep a check on if you are losing water or not.

Eric

 

There’s really nothing special about a cap used with a coolant recovery tank. Any pressure cap will do, just make sure it is good for at least 12 PSI or more. Antifreeze expands even more than water for a given temperature rise so the cooling system needs to be able to vent off excess pressure that exceeds the cap rating when hot, that’s what the overflow is for. If you just ran an “open” cap, the coolant expansion and sloshing around during normal stop-and-go driving would eventually all empty out through the overflow. Also as jbhf250 pointed out, you would have no pressure in the cooling system to prevent steam flashing (and eventual cracking) in the cylinder head hot spots. All caps have an automatic return valve in the center that allows air (or liquid from the expansion tank) to re-enter the cooling system when everything has cooled down and contracted. I guess this is the long answer for just stick a bottle on what you got.

 

Well gentleman, once again you have helped me out considerably. I appreciate your help and education on how everything works rather than a "Do it/Don't it" reply. Man, if you all start requesting a case of Pepsi/Beer for your advice and time, I may have to change jobs so I can sneak some cases out the back. Thanks again for your assistance. You folks are better than any Chilton's/Haynes manual I have read any day of the week!!

Mike

 

hol, it has been my experence for many years to check the water and engine oil while it is cool, like first thing in the morning. There should be about two inches of air space between the neck and top of the water in the radiator. If you drive the truck several days and the water level seems to be unchanged, and if you drive the truck for 20 or more miles and it is unchanged, you could go to weekly or by weekly checking of those two items and still be safe.


John

66 F100s
In the still cool hours of the night, you can hear chevys rusting away.

 

John,

Thanks, that helps. I have only been driving the truck short distances since pulling it our of the garage last month. I topped off the radiator once I pulled it out because I thought it was low. Last weekend I took it out for a 15 mile trek and it is nearly at the level you described. I was going to fill it again the other night, but have not had a chance to run the truck this week because of my work schedule. I ran across this kit while cruising through the auto parts store and thought it might be a good way to monitor the water level. Thanks,

Mike

 

>>Man, if you all start requesting a case of Pepsi/Beer for your advice and time, I may have to change jobs so I can sneak some cases out the back. Thanks again for your assistance.<<<
Hey, that would be just fine!!
Please add Berringers White Zinfandel to the order, for the wife of course...
__JOHN__Õ¿ö
72 F-250
ICQ#6030753
http://clubs.excite.com/comm/area/pw/welcome/main.asp?cid=188005&auth=

 

Consider it done. Can't leave out the other halves!

Mike