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Thermostat hell

Discussion in 'Gen 3 Prius Technical Discussion' started by Cap'n Steve, Apr 17, 2017.

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  1. Cap'n Steve

    Cap'n Steve Junior Member

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    I have entered thermostat hell. Yes, I'm one of the guys wanting to try a sealant for my head gasket leak. Of course it says remove thermostat. Assuming what I'm trying to remove actually IS the thermostat housing, how the hell do you get that out? I've removed the air intake of course. And I have 2 of the 3 nuts off the thermostat. But what in the actual fock am I supposed to do to get that 3rd one? Ok...Stop laughing at me. I'm not a mechanic, although mechanically inclined. Advise and ridicule in 3...2....1...

    2010
    202k mi
     
    #1 Cap'n Steve, Apr 17, 2017
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  2. Cap'n Steve

    Cap'n Steve Junior Member

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    And now my water pump makes a funny sound like it's drowning every few seconds. And I can't seem to drain the system. Only trickles from the petcock. Opening the reserve tank helps a little. Bit the reserve stays full with the petcock open.
     
    #2 Cap'n Steve, Apr 18, 2017
  3. bisco

    bisco cookie crumbler

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    sounds like you have air in the system. i think there are threads here on how to bleed it properly. all the best!(y)
     
    #3 bisco, Apr 18, 2017
  4. Mendel Leisk

    Mendel Leisk Patron saint of newly poured sidewalks

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    Attached Files:

    #4 Mendel Leisk, Apr 18, 2017
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  5. Cap'n Steve

    Cap'n Steve Junior Member

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    Unlike many, I did my searching in here before posting. I did find that schematic, and some helpful videos. None if which prepared me for the pain of getting that thermostat out. Contortionist indeed! Maybe I've just reached my frustration point with this car.

    I found the air leak that was letting air into the coolant system. So the water pump has stopped complaining. But I have no heat or AC now.lol. I'm sure that's my fault... but I have no idea how I caused that. Did I ruin the heater core or something? I appreciate the feedback guys. I'm just trying to juggle this car stuff with my busy family of 5 life. I'm sure some can sympathize.
     
    #5 Cap'n Steve, Apr 18, 2017
    Last edited: Apr 18, 2017
  6. jdenenberg

    jdenenberg EE Professor

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    You have an air bubble in the coolant system. Look for instructions on "bleeding" or purging air out of the ICE coolant loop. It can be tricky. My dealer blew it once and had to put my 2004 Prius on a trailer back to his shop as I wouldn't drive it when it was overheating.

    JeffD
     
    #6 jdenenberg, Apr 18, 2017
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  7. Cap'n Steve

    Cap'n Steve Junior Member

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    I may be good on the bubble now. The big question now is my AC and Heater. Any thoughts on how I messed those up in this process? The only electric plugs I touched were the one on the air intake, and the one on the dipstick. I don't know what either do. Other than that, I did leave the heater and defrost on for a long period of time to let the sealant work. Not sure if I burned something up doing that. Ugh.
     
    #7 Cap'n Steve, Apr 18, 2017
    Last edited: Apr 18, 2017
  8. Montgomery

    Montgomery Senior Member

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    Ok, so that I am on the same page with you, basically, the original issue was a leaking head gasket? And to avoid massive money lost in repairs you decided on using a sealant that instructed you to remove the thermostat? If this is what you were attempting to do, the thermostat may be needed in order for your onboard computer to function properly. I may be wrong, just my advice, but in newer cars, temperature is everything for a car to run correctly. If it doesn't warm up in a specific preset time frame, it could set other issues into motion. If its not the thermostat, they the AC may need to be bled. The compressor on our cars is unique to the Prius only and should be evaluated by a dealer.
     
    #8 Montgomery, Apr 18, 2017
  9. Cap'n Steve

    Cap'n Steve Junior Member

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    That's the gist. Of course, I couldn't quite get the thermostat off. So I did the sealer with it on.

    This is my 4th different sealer. The others were simple pour in types that required nothing from me. One of which worked great for 5k miles. That's why I stepped up to an expensive sealer. Thinking this could hold for 50k miles. :) But now no AC or heater. What did I do? Could the sealer really have messed up the thermostat?
     
    #9 Cap'n Steve, Apr 18, 2017
  10. Montgomery

    Montgomery Senior Member

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    My guess is yes it did. Those sealers are really better for older engine blocks than new vehicles due their "clogging" properties that are made to seal small flowing areas. I wish you the best at this point. You may have to get a new thermostat or a used engine.........whichever is easier, affordable or both.
     
    #10 Montgomery, Apr 18, 2017
  11. Cap'n Steve

    Cap'n Steve Junior Member

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    Well....A thermostat is 30 bucks. So I don't think I'll be getting a new motor if that's the AC issue. Anyone know if the AC is related to the thermostat??
     
    #11 Cap'n Steve, Apr 18, 2017
  12. stevelamm

    stevelamm New Member

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    Hey Cap'n Steve. Did you ever get this resolved? I have almost the exact same issue.
     
    #12 stevelamm, Oct 6, 2019
  13. GFO

    GFO Member

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    If it's not already been said, there's no cheap or easy fix for a damaged head-gasket, no amount of sealer will fix it, at least not in the long run. All you're going to do is throw money and gunk up your cooling system.

    Edit: Just realized this is a two year old thread...
     
    #13 GFO, Oct 7, 2019
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