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encouraging news with radical approach - blown headgasket

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by kobear18, Nov 30, 2021.

  1. jzchen

    jzchen Newbie!

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    @TMR-JWAP I didn't mean to suggest that someone run their car without a radiator cap in place. It was reported that the EVANS runs at very low pressure. I just checked and pure ethylene glycol boils at 386.6 F or almost 200 C (197 C more specifically). There is little surprise that at 95 + % ethylene glycol (EVANS) that the system will not build up much pressure. The fact that it has poor heat transfer properties (hence coolant is mixed 50/50 with water) also bolsters that. kobear18's goal is to keep the engine running warmer and maybe this will help allow that. I was just answering what was brought up by someone else.

    Yeah we definitely do what we have to do. If I wanna get to drive a Porsche around sometimes I gotta do what keeps the wife happy....

    REVVL V+ 5G ?
     
  2. TMR-JWAP

    TMR-JWAP Senior Member

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    That's odd, the ice car's I've had that had no thermostats always ran cooler. Maybe I just got lucky and they didn't have alternate flow paths.

    If coolant goes through the radiator too quickly and can't get cooled down, wouldn't the coolant also flow through the engine too quickly so it doesn't get heated up? Something to think about. Maybe there's something else going on with those cars that overheat when no thermostat is installed.
     
  3. ASRDogman

    ASRDogman Senior Member

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    Without a thermostat, the coolant flows continuously. With the thermostat,
    it stops the flow, or restricts it, around the block it gets hot, then the thermostat opens and it
    flows through the radiator to cool it down.
    The thermostat opens and closes to keep the coolant at the optimal temperature so the engine
    runs at it's most efficient.
     
    Mendel Leisk and jzchen like this.
  4. kobear18

    kobear18 Junior Member

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    When coolant is cool and it runs through the radiator quickly will keep it cool a lil longer but eventually the coolant will get hot. When its hot, it runs through it quickly and probably won't cool down so its its either too cool and too hot later on.

    My info was base on google search and youtube vids. ICE cars will get much hotter when sitting in traffic.
     
  5. jzchen

    jzchen Newbie!

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    I am not one who follows pulse and glide. I am slow, (not necessarily slow but I'm not flooring it), and steady. I find that I usually end my trips with 1 to 2 empty bars at the top of the HV battery meter. The car will use the battery when I am in traffic, stop and go, or at parking lot speeds.

    REVVL V+ 5G ?
     
  6. TMR-JWAP

    TMR-JWAP Senior Member

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    I'm just putting stuff out there to try to help open minds. I'm pretty sure I have a grasp on cooling systems. Not all thermostats are a single flow restriction in a single path which may or may not be directly to a radiator. Alternate flow paths can be the death of an engine when they are misunderstood. Google 351 Cleveland flow restrictor for a good example. Most cars that overheat when sitting still are victims of a failed fan which doesn't create adequate air flow through the radiator or improper shrouding which allows heated air to recirculate back to the front of the car immediately after it passes through the radiator, where it is then pulled back through the radiator again, each time being a less efficient heat sink.

    My info is based on ........other stuff
     
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  7. Tombukt2

    Tombukt2 Senior Member

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    With Evans you're running a zero pressure system your pressure cap is removed and you put a cap that does not have a spring in the top of it and creates a zero pressure system not 10 lb not 5 lb 0 lb that's Evans that's that stinky 18-wheeler cooling is what I call it that's where it's been used most of its life the car people got a hold of it in the mid-90s and I've used it in a couple Toyota celica's w 4tgte engines. Group A spec

    SM-A715F ?
     
  8. Tombukt2

    Tombukt2 Senior Member

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    The water has to have some dwell time in the radiator to shed its heat the way that's done is with the thermostat or a restrictor plate it slows the water down so it dwells a little in the radiator with no restrictor or no thermostat The water runs round and round like an F1 car on the track The water is just flying through there it can't shed the heat that is constantly getting into the coolant water mixture because it won't dwell in the radiator where the air can fly across it and remove the heat is my understanding of the process if you use Evan's coolant you use a different radiator cap with zero pressure it's right there in Evan's literature I've run this in a couple 4T engines

    SM-A715F ?
     
  9. kobear18

    kobear18 Junior Member

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    first of all, I don't like ethylene glycol at all. Its very toxic. Another thing I did to my prius was to block the air vent completely. Not sure if every1 knows where that is. You have to remove the cowling and the entire wiper assembly to see it. Its where the so called "fresh air" come into the cabin. Its not fresh air. Its all the shitty air from the engine especially after the head is cracked. Some coolant vapor may come out from the expansion tank and you will be breathing it. I got very serious allergy and I got very sick from that so I completely seal the that air vent. Now I know that my prius may never over heat again so I just pour water filtered water in. I would say now its 80% water and 20% of that 50/50 pink coolant left. Another thing I notice is that the pressure is much less now in the cooling system after taking out the thermostat. It used to be like coolant jetting out from expansion tank every time I open the cap. Sometimes, the pressure was still high after 1 full night on driveway. I opened the cap in the morning, coolant still jet out. It should NOT be like that at all. Right now, if I open the cap 1 hour after driving, there is almost no pressure at all. I don't know who created this bull shit thermostat. We don't need it. It crated more problems so we can buy new cars sooner. I bet there are many other things they put in our cars just to kill it sooner so we can all buy new cars sooner. fuk this BS.

    Another thing about my MPG, it stays at 50.5 now. If I drive freeway more, maybe it will go up a lil to 53. Now it has been 360 miles after thermostat is out, some freeway & mostly local roads. 50.5 is what i get. Not bad at all.

    I recommend every1 to take the thermostat out and your car will never over heat and the water pump will never run dry. Just put some R-13 insulation to cover the front, that is all you need to keep the coolant warm enough.
     
  10. ASRDogman

    ASRDogman Senior Member

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    You should probably find out WHY it's overheating. You are dealing with symtems, not the cause.
     
    #30 ASRDogman, Dec 7, 2021
    Last edited: Dec 7, 2021
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  11. jzchen

    jzchen Newbie!

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    You might want Red Line WATERWETTER to help prevent corrosion. (I just checked and it notes "no ethylene glycol".



    REVVL V+ 5G ?
     
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  12. kobear18

    kobear18 Junior Member

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    Thank you for letting me know but I want warmer temperature now. I dont want the coolant temp to drop 20 to 30 f. Wat i got now is perfect. Local roads 135 to 145. Freeway 175 to 185. That is perfect. The only thing left to do is probably just use all distill water.

    The cooling system is fine. It was just the cheap ebay thermostat not openning fully during higher temp. I also think that having a Aisin one wouldnt help much either. W/o this bs thermostat is perfect.
     
    #32 kobear18, Dec 7, 2021
    Last edited: Dec 7, 2021
  13. Tombukt2

    Tombukt2 Senior Member

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    In my other equip I use robertshaw balanced stat. Seems to work ok . I gotta 13 I could play all these games with . Well could've with no compression on No 2 now me thinks pointless

    SM-A715F ?
     
  14. ASRDogman

    ASRDogman Senior Member

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    sooo,,,, you put in a cheap thermostadt and aren't happy with how it works....
    Wow,, I'm surprised....
    Perhaps spend a few dollars more and put in a good Toyota thermostat....