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Prius c coolant in oil

Discussion in 'Prius c Technical Discussion' started by Jason254, Sep 29, 2024.

  1. Jason254

    Jason254 Junior Member

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    Vehicle:
    2012 Prius c
    Model:
    Two
    I have a 2013 prius c that is loosing coolant into the oil. The oil is a milky white ish color. There are no visible drips or leaks.

    I got a test kit for head gasket leaks to see if there is any combustion gasses in the radiator. But after a good 10 minutes of idling the car no exhaust gas was detected and the fluid stayed blue. I would think after 10 minutes the thermostat would open and I'd detect exhaust. Also, I did not visibly see any vapors when I opened the radiator cap.

    Either my kit didn't work and the gasket is bad, or the coolant is getting in the oil other than the gasket. After about 20 miles of driving with fresh oil it's already visibly milky so I don't think the leak is all that slow.
    In a Google search the AI said it could be a failing water pump as well. Not sure how much I trust AI to give me a good answer though.

    I was thinking of bringing it to a prius specialist near me and see if they diagnose what it could be, but wanted to see if anyone else has had this issue and what the problem could be. Also, I should mention the car starts and runs fine. No white smoke or rough starting.

    Thoughts?
     
    #1 Jason254, Sep 29, 2024
  2. ColoradoBoo

    ColoradoBoo Senior Member

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    Vehicle:
    2017 Prius
    Model:
    Two
    No it doesn't sound like a blown head gasket but could be a cracked block or cylinder head, not good news, sorry!
    Since it's an engine problem, no need for a hybrid specialist to diagnose, imho....any good mechanic should be able to troubleshoot.
     
    #2 ColoradoBoo, Sep 29, 2024
  3. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Vehicle:
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    Model:
    Two
    A test for combustion gases won't ever activate if the breach is between coolant and oil.

    There are 7 ways for a head gasket to fail. Here's a reference.

    The test kit you bought can only detect/confirm type 7. The symptoms you describe match type 3.

    Have you verified that you are losing coolant? (Not that there are many other sources of water available, but it's a thing to check)
     
    #3 Leadfoot J. McCoalroller, Sep 29, 2024
    Mendel Leisk likes this.
  4. Jason254

    Jason254 Junior Member

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    Vehicle:
    2012 Prius c
    Model:
    Two
    The car is definitely losing coolant. I wasn't aware it's possible to have a head gasket leak but no exhaust gasses. But #3 would explain the car runs fine. The combustion chamber is dealing with coolant.

    I'm trying to decide what to do with the car. Try a gasket sealer or get rid of it. Neither choice is a good one. I can't afford to fix with a new gasket or a replaced engine.

    I'm guessing a gasket sealer wouldn't work in case 3?
     
    #4 Jason254, Sep 29, 2024
  5. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Two
    I couldn't say. I've got a very low opinion of sealers in general- I look at it as something you put in the car so you can escape from a dangerous situation, then throw the car away afterwards.

    I know it can create clogs in the radiator and heater core- the former isn't hard to replace but the labor for the latter is insane.

    Not a good situation, I wish you luck either way.
     
    #5 Leadfoot J. McCoalroller, Sep 29, 2024
  6. MAX2

    MAX2 Member

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    Is there really coolant in the oil?
    Have you tried mixing some oil and coolant in a clear container to see the color and consistency of the experiment?
     
    #6 MAX2, Sep 30, 2024
  7. Jason254

    Jason254 Junior Member

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    Vehicle:
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    Model:
    Two
    I can try that test. But I'm 99% certain coolant is in the oil. The car lost coolant w/o any external leak and started to overheat. Then I saw milky white oil.
     
    #7 Jason254, Sep 30, 2024
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