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Keeping the engine cooler

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Taxi/Limo, Oct 3, 2016.

  1. Taxi/Limo

    Taxi/Limo Active Member

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    Hello All
    I noticed my 2010 Prius III not Three runs from 70 to 90 Celsius
    Is that normal?
    Would it be a good idea to try to get it to run a little cooler?
    If so how can one do that ?
    Thanks

    Nexus 6 ?
     
  2. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    The thermostat in my 2012 Prius v is set for 195F which is 90C, so when it gets to 90C in the engine coolant flows to the radiator.
    For it to stay above 90C for any length of time the radiator would have to be inadequate to cool the engine.

    Stant

    I am not sure why you would ever want to change this, but you could go to your dealer and buy a lower temperature thermostat.
     
  3. bisco

    bisco cookie crumbler

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    have you considered freezing bottles of water, and storing them in the engine bay?this works quite well for cooling the battery.
     
  4. Raytheeagle

    Raytheeagle Senior Member

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    Maybe this thread will get over 100 posts on how to lower temps 1 or 2 degrees just like those frozen bottles :).

    But we might get there with double posting though(y).
     
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  5. StarCaller

    StarCaller Senior Member

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    good luck with finding a lower temp thermostat for a generation 3....
     
  6. exstudent

    exstudent Senior Member

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    Assuming all cooling parts on your 2010 are OEM, or have been replaced with equivalent parts that will operate at the same parameters as the OEM parts, your car will operate as it was programmed for maximum efficiency. So, NO. Leave the car be, and just drive it.

    The car is programed to operate at maximum efficiency based on various inputs from:
    engine/coolant temperature, AC or Heater demand, Gas Pedal input (mild, moderate, heavy gas pedal depression), etc.

    As someone pointed out, changing the thermostat to a lower or higher degree thermostat, will affect the engine operating temperature, which will have an impact on your efficiency.
     
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  7. Toppcat

    Toppcat Member

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    90 c is Normal operational temperature! Unless you can rewrite new map programs for the ecm. Then try drill out bleeder hole in the thermostats this will allow more flow! Drain entire coolant system engine block too! Refill with distilled water and redline metal wetter! If your planning to run engine for long periods of high rpm s like 5000 + should see a 10-20 degress reduction engine temp. You can also have the radiator customize adding a extra row of veins. Cutting out bigger opening for the radiator to allow more air flow, air scoops too!
     
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  8. BruceInOKC

    BruceInOKC Member

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    No, it's not a good idea to run cooler than the designed operating temperature. If your engine runs cooler, it's less efficient, which lowers your mileage. If your engine runs cooler, it increases the water and fuel condensation in your oil, which increases engine wear.
     
  9. Taxi/Limo

    Taxi/Limo Active Member

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    okay
    I was under the impression a cooler running engine would last longer
     
  10. RRxing

    RRxing Senior Member

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    Just the opposite. A fully warmed-up engine is at its most efficient. As far as the engine lasting longer if running cooler - a BIG maybe - but not worth the loss in efficiency and not worth the cost of any modifications. 70-90C is perfectly normal. Let the car run as designed.
     
  11. Jimi1976

    Jimi1976 Active Member

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    Yes - I believe the Beatles wrote a song about this subject LOL
    IMG_7210.JPG
     
  12. Taxi/Limo

    Taxi/Limo Active Member

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    Beatles so what about reducing friction ? Any oil or oil additives I can use?

    Nexus 6 ?
     
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  13. Mendel Leisk

    Mendel Leisk Senior Member

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    Just ensure it's 0W20, and don't overfill.

    You're monitoring engine temp with something, ScanGuage, or a phone app? Anyway, the 70C to 90C temps you're seeing is very similar to us. A regular car will get up to 90C and stay there, perfectly normal. The Prius, for various reasons, and especially in winter, tends to run cooler.
     
  14. Raytheeagle

    Raytheeagle Senior Member

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    Next oil change I am going to put in BG products MOA. I use 5W-30 synthetic currently with a oil change every 10k mile interval. Did the BG Products EPR cleaning last oil change and the oil came out jet black, so some deposits were removed.

    This change will be MOA then the following change will be the extended life MOA.

    Going the controlled experimentation route to gauge performance;).
     
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  15. Taxi/Limo

    Taxi/Limo Active Member

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    BH Moa?

    Nexus 6 ?
     
  16. Raytheeagle

    Raytheeagle Senior Member

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    Yup.

    Google BG Products and you'll get to Motor Oil Additive (MOA). Some interesting stuff and good videos if you have time:).

    It will add cost to an oil change, but if you DIY, it is cost neutral or positive when compared to dealer oil changes;).

    The EPR helped smooth out the idle, made the fresh oil look cleaner on the dip stock and reduced oil consumption in my case. I have also used the 44K fuel cleaner.
     
  17. Robert Holt

    Robert Holt Senior Member

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    +1 to NOT changing the thermostat or attempting to make it run cooler than 90 Celsius, 195 Fahrenheit .

    In fact, many posts in in PriusChat involve blocking parts of the front air intake to help the engine warm up more quickly to the standard operating temperature . Since I have installed movable grill blocks , I use a Scangauge to track engine temperature and have found that the blocking lets the ICE get to 195 more quickly on cold mornings. Watching the mpg estimates vs engine temps, FWIW, I also observe that the mpg estimates when the engine is warming up to that operating temperature are noticeably less than when the engine has reached its normal operating temp.
     
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  18. Kenny94945

    Kenny94945 Active Member

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    I leave to the experts, but can add this:
    a) Make sure there are no leaves blocking the radiator fins.
    b) Make sure grill and lower diffuser/ air vent directors are A-O-K.
    c) Make sure radiator coolant is fresh/ tests within specs.

    I'd assume the OEM system is just fine for most areas.
    Siberia/ snow belts and Saudi Arabia/ desert could have different specs...again I'll leave to the experts.
     
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  19. Toppcat

    Toppcat Member

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    I don't recommend addtive to synthetic oil each manufacturer has its own blend to deliver it's design performance! adding foreign chemicals changes the chemical structure .
     
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  20. Jimi1976

    Jimi1976 Active Member

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    What makes you think regular synthetic oil is not working?
     
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  21. Taxi/Limo

    Taxi/Limo Active Member

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    I suppose it is but I believe I have seen Royal Purple do a better job than mobile 1 in reducing friction on youtube

    Nexus 6 ?
     
  22. Jimi1976

    Jimi1976 Active Member

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    Then try the royal purple.
    Worst case : you just spent twice as much on oil for no reason.
    Best case: it lubricates the motor. Motor doesn't blow up.
     
    #20 Jimi1976, Nov 8, 2016
    Last edited: Nov 8, 2016