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  1. #1

    cold radiator under pressure??

    Guys,

    I opened up my radiatorcap today and the car was standing for over a week so was cold . It still had pressure on it and some coolant got spilled in less then a second of course.

    I have a few questions concerning this...

    1. Is this a normal situation?
    2. Is this because I use the st165 overflow tank which also has a pressurecap?
    3. Can I test if above tank is still working properly ?
    4. Can I replace above tank with my st162 tank which has no pressure cap and does this give me an advantage or disadvantage?

    thanks guys ! Btw, it stopped leaking from the heating hoses at the moment and I don't need to fill her up at the radiator plus it won't get overheated, so I guess it's working fine now?

    http://www.celicas.eu - Founder & member of honour

  2. #2
    Nobody?

    http://www.celicas.eu - Founder & member of honour

  3. #3
    Donated!
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    i would imagine that the pressure does stay because of the pressure cap on both the rad and the overflow. no way can get out.
    if you did the same exercise when hot, you'd get more explosion, but with your car cooling down, i assume that while the lower temp returns the pressure to low, there is still some 'leftover' pressure? similar to a cola bottle, even if you don't shake the bottle, you'll still get that pfssss sound.
    this is taking strictly from high school physics LOL no experience at all with st165s
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  4. #4
    Senior Member Spiderman's Avatar
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    The fact that you havn't driven it for a week tells me your not enjoying the amount of work you have put into the Wolf ?


    Second......... if you had pressure after a week tells me 2 things or nothing.......... You either have the best hose system in the universe or your on drugs.


    A radiator overflow tank is there for one reason....... to 'catch and suck' during hot and cold operation........... If there was a pressure cap on my overflow bottle I'd sure as shit blow something else and need to replace.


    I know this has been discussed many times before and nearly forgot that it depends on the radiator cap temp PSI and will depend when to "DUMP" into the overflow bottle so feel free to correct me if I'm wrong.

  5. #5
    Yes it's normal.

    On my swap I have the ASI/AutoPWR ST165 radiator. I had to pull the upper radiator hose a few days ago when I was dropping the transmission. As soon as I pulled the upper hose it just vomited coolant out. It was sitting for like 2 or 3 weeks.
    Sold.....

  6. #6
    Quote Originally Posted by Spiderman View Post
    The fact that you havn't driven it for a week tells me your not enjoying the amount of work you have put into the Wolf ?
    Not to be true...at this moment the IC cooling is not functional as it was leaking expensive red fluids and I drained it untill I have my new hoses. Before that I don't really have much cash to spend and gas is over 1,80 Euro/liter at the moment... Another fact is I'm unemployed and also the 24/7 babysit for tim and when the wife's at home I like to spend some time with her as well . She luckily still works. And the sun doesn't shine too much so rain is a no go for my beauty.

    But...don't worry, when my IC piping and heater hoses are looked after I will start driving again, like on the ring in july Maybe hit 200+ km/h sometimes when heading over there in germany ..

    http://www.celicas.eu - Founder & member of honour

  7. #7
    Super Moderator ST165-2765's Avatar
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    Quote Originally Posted by lone wolf View Post
    1. Is this a normal situation?
    2. Is this because I use the st165 overflow tank which also has a pressurecap?
    3. Can I test if above tank is still working properly ?
    4. Can I replace above tank with my st162 tank which has no pressure cap and does this give me an advantage or disadvantage?
    1. I do believe it is normal, my RAV4, GTS & All Trac all do it and only the All Trac has a pressurized overflow tank

    2. No, it is because your cooling system is sealed well

    3. I think the only thing you could test is the overflow tank pressure cap

    4. I wouldn't, IIRC toyota originally shipped the ST165 with a non pressurized overflow tank and then did a recall to swap in the pressurized overflow tank

    I am guessing it has to do with how hot the turbo can get and how close it is to the radiator. Your looking at a radiator that likes to be at a couple
    hundred degrees absorbing heat from a turbo that can get to a couple thousand degrees and normally thats okay cause the engines running and the
    coolant is circulating but when you turn the car off that poor radiator has to soak up alot of heat(expand) so I think they needed to provide more area
    for the coolant to expand into.


    1988 All Trac ST165-0002765 rustbucket
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    It's not impossible, it just costs more

  8. #8
    The other thing to think about....

    The radiator cap opens under a certain pressure (mine for example at 1.1bar). Anything less than 1.1bar it will stay shut. So in theory, I could of had 1 bar of pressure in my radiator since I shut the car off and it's been sitting there. It's not a bad thing at all, like stated above it just shows that your cooling system is very well sealed and you have no leaks.
    Sold.....

  9. #9
    lol So the opposite of what I first had, leaking hoses...

    http://www.celicas.eu - Founder & member of honour

 

 

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