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Trick to removing the coolant resevoir cap?

Discussion in 'Prime Main Forum (2017-2022)' started by Michael Wood, Jul 9, 2022.

  1. Michael Wood

    Michael Wood Active Member

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    I noticed that the coolant level on my 2020 Prime is at the LOW mark on the reservoir (cold engine). There are 2 marks, LOW and FULL. I can't remember if it's always been at LOW when the engine is cold. 18k miles. So that's my first question - what do you guys see?

    Secondly.....when I tried to remove the cap I got a lot of resistance, unscrewing counterclockwise. Didn't want to force it so I stopped and thought I'd ask if anyone else experienced this, or if there's something I'm missing. Like, maybe it's not a screw cap?

    Thanks!
     
  2. Mendel Leisk

    Mendel Leisk Senior Member

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    If it's like third gen it takes a bit of force: there's a tab semi-locking it. You need to push through that initial resistance.

    That said, with only 18K, you may have a leak in the exhaust recovery system. It's an issue with 4th gen, Toyota's aware of it and offering free repairs. Check with dealership.
     
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  3. Michael Wood

    Michael Wood Active Member

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    Will do. Thanks for the "heads up"!
     
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  4. PT Guy

    PT Guy Senior Member

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    @ low when cold is OK if it doesn't go down farther. I'd watch it and see if it changes when at the same temperature.
     
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  5. jerrymildred

    jerrymildred Senior Member

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    It just unscrews like any other cap, but it has a bit of resistance until it's almost off.

    Mine has almost 68k miles. Bought at about 23k. I've never added to my reservoir and it's still a hair over the full mark cold. Well, as "cold" as it gets here this time of year.
     
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  6. Mendel Leisk

    Mendel Leisk Senior Member

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    It took me roughly 5 years of ownership and 32K miles for engine coolant to get down to low mark. Inverter coolant did the same. Topped off both and they haven't budged since. A 2020 with 18K miles having engine coolant down to low mark seems a little premature. I'd top it up and monitor, with Toyota Super Long Life Coolant. Monitor closely cus there is a 4th gen issue, with the exhaust heat recovery system.

    From my log:

    ====
    Friday, April 03, 2015
    km: 51198
    * changed engine oil and filter
    * lubed all hinges
    * checked both air filters (blew out and reinstalled, look good)
    * topped up both coolant reservoirs, both were near bottom line
    ====
     
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  7. Michael Wood

    Michael Wood Active Member

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    I have to take it in for a state inspection sticker anyway, so I'll have the dealership take a look and post the outcome. I suspect it's dropped an inch in the last 12 months. Thanks for the help.
     
  8. Michael Wood

    Michael Wood Active Member

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    Here's a pic of the reservoir.
     

    Attached Files:

  9. Michael Wood

    Michael Wood Active Member

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    The dealer said "all the Primes do that". They topped it off, and I'll keep an eye on it. I was surprised they didn't try to charge me $100 for the top-off.
     
  10. bisco

    bisco cookie crumbler

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    if it has the same exhaust loop as other gen4's, it could be leaking.

    they don't 'all' do it, but it has been an issue
     
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  11. jerrymildred

    jerrymildred Senior Member

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    Neither of our 2017's do that.
     
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  12. PT Guy

    PT Guy Senior Member

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    My 2017 is at the low mark when cold now after almost 5 years of service. I just picked up a jug of Valvoline Asian Red antifreeze so I can add an inch or two. I'd only use the Toyota coolant, or Prestone Asian Vehicle Red or Valvoline/NAPA Asian Vehicle Red.
     
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  13. Michael Wood

    Michael Wood Active Member

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    The TSB I read covered Prius' 2016-2019. Maybe the dealership blew it off because there isn't a TSB yet for 2020 Primes? In any case, I'll keep a close eye on it and if it drops again I'll push them to inspect that heat exchanger. That fluid has to be going somewhere. I garage the car, and don't see any evidence of leaking. The oil looks perfect. Not sure if there's a pressure vent somewhere in the system.
     
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