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Radiator cap location

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by BruceInOKC, Jul 2, 2012.

  1. BruceInOKC

    BruceInOKC Member

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    Does anyone know where the radiator cap is located? I looked in all the obvious places, including removing the piece of trim over the radiator.
     
  2. adamace1

    adamace1 Senior Member

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    There is no cap. You have to fill the two different collants from the guages on the side of the "overflows" or what ever they are called now.
     
  3. LulzChicken

    LulzChicken Prius Enthusiast

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    I'm not sure if there is actually a cap that is tied directly into the radiator. However, here is a guide you can follow for all of the places you can add fluids:
    [​IMG]

    I know this may not be exactly what you're looking for, but I don't know if what your looking for actually exists in the first place. Good luck!
     
  4. BruceInOKC

    BruceInOKC Member

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    Thanks, guys. Ah, so there is no radiator cap, only the two coolant reservoirs. I thought maybe they had hidden the radiator cap to keep people from fooling around with it and burning themselves while the engine was hot.
     
  5. CharlesPrius

    CharlesPrius Member

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    Thanks, I was wondering the same. So I'll just add the coolant to the reservoir.
     
  6. ChapmanF

    ChapmanF Senior Member

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    Yes, Gen 3 did away with the cap. Gen 1 and 2 still had the traditional cap, with the plastic reservoir being a traditional 'overflow' tank.

    Gen 3 has no radiator cap, and the plastic reservoir is permanently in the circuit; when the engine's up to temp, you'll see coolant recirculating right through it.

    If you are filling after a full drain, you'll see there's a "B" mark on the reservoir, up above the normal "F" mark. If you fill it to there (which is just about where it will start running out the bleed valve you opened back by the firewall), then close the bleed valve, start the engine, warm it up while burping the hoses, shut down and let it cool, the level ends up right on the "F" line. The engineers really dialed that procedure in, they knew just how much air has to burp out. :)

    -Chap
     
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