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2012 156k Water Pump

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Noahdoge, Aug 1, 2022.

  1. Noahdoge

    Noahdoge Active Member

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    Replaced my water pump as preventative maintenance. Attached you will see the excellent condition the original pump is in. I was surprised that there was absolutely no difference in resistance to the new one. Took it apart to take some pics for the group. It definitely could have gone a lot longer before needing replacement.
     

    Attached Files:

  2. PriusCamper

    PriusCamper Senior Member

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    That sure is a lot of work to do on something that didn't have anything wrong with it?
     
  3. Noahdoge

    Noahdoge Active Member

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    I agree. But I guess there is no way of really knowing if it is on the road to failure. Since it’s a brushless motor, I was more worried that I would get a code on the interstate far away from home. Maybe it was a waste of time to replace early but $200 peace of mind knowing both my old pump was good and the new one will last the rest of the engines life.
     
    #3 Noahdoge, Aug 1, 2022
    Last edited: Aug 1, 2022
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  4. JC91006

    JC91006 Senior Member

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    This is definitely a preventive maintenance item, like a timing belt. You don't wait until it breaks before you change it. This could be a contributing cause to all the head gasket failures, when this brushless motor weakens and not work as intended to cool the engine. You won't get a code until it's too late.

    Similar to the inverter pumps, they don't crap out and stop working completely. They'll keep working at a reduced flow level until it breaks down completely.
     
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  5. PriusCamper

    PriusCamper Senior Member

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    Are you blind to the results of the health of the pump that was replaced? And yes back in the 70's certain vehicles with a known history of timing belt failure would replace them at a certain mileage, but that was a 1/2 century ago when engine technology was far less advanced. You never have to replace major engine parts as preventative these days. If you do, you're your delusional or you're trying to scam someone.

    You won't find a single ACE certified mechanic who is going to tell someone to replace a water pump before it shows signs of failing unless they're a scammer who deserves to lose their certification. Some people get 400K miles out of their water pump and something else is way more likely to fail before this simple pump does.
     
  6. 2010moneypit?

    2010moneypit? Active Member

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    I am an ASE master tech. I disagree with you Prius camper however we are all entitled to our own opinions. I replaced my water pump for preventative maintenance at 200,000. I also have replace water pumps on other prius cars at around 200,000 The pump is expensive but it’s worth the peace of mind. (I use dealer only too many problems with aftermarket parts). You don’t know when they are going to fail. The labor is not that much to change them. But if you are on the side of the highway it is a huge inconvenience. I don’t feel like I am scamming people. I’m sorry you feel that way.
    I do agree with you you may get 400,000 miles and you may not. Also you could have many other things fail before the water pump fails. I still like to change the water pumps at around 200,000 miles. These cars don’t have temp gauges. A lot of people will ignore the check engine light when it comes on.
     
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  7. JC91006

    JC91006 Senior Member

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    I changed my pump on my 2010 at 140k miles. I don't regret doing it at all. It was perfectly functional when I replaced it, but it was 11 years old at the time. Since the car went to my daughter, I wouldn't want her stranded somewhere because I tried to save a couple hundred bucks. I consider this pump a once in a lifetime replacement for me. I rarely keep a car past 250,000 miles, so doing it at 140k or 200k, it would still be a one time event.

    You have to remember this turd gen car is not the same as the 2nd gen you're driving. The mentality is completely different when it comes to replacing parts on these cars.
     
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  8. Eddie25

    Eddie25 Active Member

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    The lack of a temp gauge on these cars definitely makes it a maintenance item in my opinion as well, especially with how common head gasket failure is. I'm at 192k and recently bought one to be installed around 200k. I might push it a bit since I monitor my temps fairly regularly.
     
  9. PriusCamper

    PriusCamper Senior Member

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    Yeah, every time I've dealt with a Prius that was running hot, I didn't need a gauge, it was obvious. That's when I use a phone app to monitor the temp until diagnosis & repairs are completed. But it is true that some might not notice and not know how to use an OBD2 for a phone app.

    But when it comes to durability of engines and water pumps in the 21st century it makes no sense to use last centuries logic about preventative maintenance.
     
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  10. Krall

    Krall Member

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    Do you also replace the thermostat with the water pump?
     
  11. ChapmanF

    ChapmanF Senior Member

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    Thermostats are such simple items that not much can happen to them.

    If the coolant hasn't been changed often enough, so the anticorrosives in it got depleted, maybe the thermostat can corrode, and not close completely, so the engine takes too long to warm up.

    If the engine ever has been severely overheated (for any reason), so the thermostat got hot enough for its expanding wax to burst out, then it's done for: it'll never open at the right temperature after that, so the engine will keep overheating even if the original cause is fixed.

    So it's definitely something to change any time you know the engine got badly overheated for any reason.

    Otherwise, and if the coolant's always been changed on schedule, it's probably a-ok.
     
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  12. JC91006

    JC91006 Senior Member

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    When I changed my water pump at 140k, I didn't change my thermostat
     
  13. Krall

    Krall Member

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    Judging from the shape the old water pump is in the thermostat will also look brand new! But for $50 and while I have it all apart I was wondering if I should 'just do it'.
     
  14. 2010moneypit?

    2010moneypit? Active Member

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    I don’t always replace the thermostat on Toyotas. Only if it has been overheated or if the coolant looks really bad.

    On the other hand on the Chevys and Fords that I work on I replace them every time I do a water pump because they have a higher failure rate.
     
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  15. Krall

    Krall Member

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    I think this adventure for me started with a 2nd head gasket sealer treatment causing issues with the water pump so when I drained the system it had silver flakes and fibers in it. I had it flushed 2 other times prior, but I don't really know the condition of the coolant this last time. I had a couple of dash warnings for overheating, but they were brief and went away on their own.

    Still I think I'm just going to replace it since it's all apart.
     
  16. Mendel Leisk

    Mendel Leisk Senior Member

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    Yeah that's the price I'm seeing as well, in CDN $'s, all-in, through Amayama. I'd opt to change the thermostat too.

    upload_2022-8-5_6-31-17.png
     
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  17. 2010moneypit?

    2010moneypit? Active Member

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    Yes replace it if you’ve done any kind of sealer in the cooling system.
     
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  18. Xterra72

    Xterra72 Senior Member

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    You are right! Mine was going out with a warning red temp light that blinked for a few seconds . Next thing you know I was losing coolant. I did not get a code because it was still
    Working . Next time I got the red high temp flashing light , I took it to my mechanic and he was able to read the code for bad water pump on his plugged in obdII. All good now.
     
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  19. Noahdoge

    Noahdoge Active Member

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    Thanks for the feedback! What year and how many miles?
     
  20. Xterra72

    Xterra72 Senior Member

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    2013 . It’s at about 208,000 miles now.

    Drove 3 round trips to Arizona this past month for a total of 4500 miles. Drove like a champ.

    5k oil change soon.