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joshuajim's avatar
joshuajim
Explorer II
Sep 05, 2018

Boiling point of anti freeze

I flushed and refilled my trucks radiator today. I noted on the bottle that a 50/50 solution of antifreeze/water will result in a 256 degree boiling point. This piqued my curiosity so I did a little research. In reality 50/50 antifreeze only raises the boiling point by 8 degrees. The 15# cap on the radiator is what gets you to 256.
  • SidecarFlip's avatar
    SidecarFlip
    Explorer III
    Sep 06, 2018
    Very good observation. Now for the fun part. Radiator caps as they age, tend to loose their ability to hold pressure in a cooling system. Caps should be replaced every couple years. Most people never do however. Mine goes in the trash every 2 years. That is especially important with a diesel motor as loss of pressurization of coolant can result in hot spots on the cylinder liners and big mechanical repairs.

    All for a 6 buck part.
  • RCMAN46's avatar
    RCMAN46
    Explorer
    Sep 06, 2018
    At 10,000 feet that temperature drops to about 237 degrees f.
  • MDKMDK's avatar
    MDKMDK
    Explorer
    Sep 06, 2018
    Good to know. Especially when I'm watching my coolant temp underway.
    Thanks.

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