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replace head gasket or the entire enginee

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by field_catcher, May 21, 2022.

  1. working1

    working1 Active Member

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    Just replaced out the 2012 gen 3 engine with 266K miles due to the head gasket issue. One other sign it's a head gasket problem is excessive pressure build-up in the coolant system. If you hear and feel a large rush of air pressure when opening up the coolant reservoir lid after it's cooled down, it's likely the head gasket. The other signs were there like shuttering, etc.

    I went with a auto yard replacement 2014 engine with 80K miles. The car drives like new. I considered a JDM engine, but, too many unknowns in terms of exact miles, etc. I don't expect to drive more than 4000 miles/year, so, I'm OK with using a gen 3 replacement. If I had plans for more drive miles per year, I'd consider the 4th gen.

    Suggest budgeting for replacing components that will be easy to replace when it's out of the car like water pump, thermostat, pcv valve, etc. Also the location of the auto yard/vehicle history makes a difference. I got one from Florida to replace a mid-west winter driven engine. Unreal the difference in one having no rusted bolts vs. the other with every bolt rusted. Stay away from a used engine out of a vehicle driven up north.
     
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  2. rjparker

    rjparker Tu Humilde Sirviente

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    Egrs are nice to clean up but don't expect it to solve your violent shuddering. Obvious loss of coolant is a late stage symptom.

    It could get worse if you "wait"
    Shudder video
     
  3. cww

    cww Junior Member

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    I think I have begun to see signs of coolant loss will confirm this tomorrow for sure. I was giving it a few days because I lost some coolant when I removed the throttle body so I want to make sure its leveled out. I have located a $1300 JDM version with like 50,000 miles which seems like the best option at this point.
     

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  4. rjparker

    rjparker Tu Humilde Sirviente

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    Its interesting how every JDM engine is sold with 50k miles on it. No vin plate does not mean its a Japanese imported engine. It can very well mean the salvage yard removed it. Do as much verification of the engine source as possible. Any indication of vin plate removal is a deal killer.

    Prius gen3 vin plate.jpeg
     
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  5. cww

    cww Junior Member

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    Yeah I noticed that, but the company offers a 90 day warranty and will even do the install for a reasonable price with a longer warranty but I’ll do my do diligence as much as possible.
     
  6. cww

    cww Junior Member

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    There is also one of the valves and hoses that is a different size so that is a give away if they include it.
     
  7. working1

    working1 Active Member

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    If you're doing the engine swap (3 gen to 3 gen) for the first time there are some online videos that show the basics. However, none of them used the exact some process I used. Some suggestions:

    - Remove the hood. Mark the 4 bolts to reference when reinstalling. Some videos show leaving it installed, but, the extra room helps a lot.
    - Remove the EGR and EGR cooler. Some videos show leaving those on during removal and installation. That makes it very hard to reach the top bolts for the transaxle to engine connection.
    - Don't disconnect the AC wiring. The AC will need to be unbolted. I used plastic tie wraps to support it vertical. Would suggest additional tie wraps to move it closer toward the front to increase clearance.
    - The water pump will need to be removed on the old and replacement engine for clearance.
    - The thermostat does not need to be removed. I installed a new thermostat on the replacement engine before installing the engine in the car. Much easier to replace it with the engine out of the car.
    - The exhaust manifold does not need to be removed on the old or replacement engine.
    - Separating the transaxle from the engine was the most difficult part the process. Fortunately, there is a drain hole cast into the bottom of the transaxle that can be used to separate them. Use a cold chisel. I used multiple cold chisels at the same time to build up enough thickness to wedge them apart.
    - The clearance is super tight when removing and installing the engine. Super tight meaning some where between .5" to 1". It can be done, just take your time and don't be in hurry.
    - Pay special attention and don't damage the flywheel damper during removal and installation.
    - Check the clearance often between the windshield and engine during removal and installation. Bumping the windshield will be costly.

    That's a quick recap and hopefully saves others time and avoidable frustration.
     
  8. cww

    cww Junior Member

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    Thank you sir, looks like I’m losing coolant so once we move in this will be one of my first projects!
     
  9. Seymour1

    Seymour1 Junior Member

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    I watched an old youtube video of the "car care nut" who installed a short block in a gen 3 car. This guy makes a lot of excuses for Toyota. With other new parts, he called it a $6500 engine rebuild. But, now the short block cost has almost doubled. But, it seems to be a better gamble than a JDM or ebay engine (which is likely flawed). But even if only $6500 plus replacing my faulty brake master cylinder, I am starting to face reality and say it is time to junk the car (although the body is in good shape). Maybe I can recondition the traction battery, and sell it plus the inverter and cat converter. I might only lose $1500 and call it a lesson learned. I will do more research before buying a car.
     
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  10. Mendel Leisk

    Mendel Leisk Senior Member

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    @Seymour1, you've got nine threads started, on this one car. Maybe pick one of those to post updates/thoughts in? Just copy the above, paste it into the most up to date thread you've started, then delete the text here, say replace with "deleted".
     
  11. ASRDogman

    ASRDogman Senior Member

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    There is a difference between a shop replacing it, and an individual. A shop has alot
    of liability, an individual doesn't.
    Contact hybrid pit, the have remanufactured for about $2300.00.
    Get the Prolong charger/discharger for $700.00. It's easy to install the harness.
    I would say it will take some skill to replace the brake components.
    But if you had a shop do that and you do the rest, it's a lot less money.



     
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  12. Seymour1

    Seymour1 Junior Member

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  13. Seymour1

    Seymour1 Junior Member

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    O.K. Thanks. I am new to this. I think that what I should do is to find one of my old posts or find any with the same subject and just add to that thread. Is that right? I will do that.
    Sometimes I had trouble finding my old post and then started a new one. Then, I found that I can search for my user name.
    I hope that this post only goes to you and not to too many on the website.
     
  14. Mendel Leisk

    Mendel Leisk Senior Member

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    No worries. To find your post history, click on your avatar:

    upload_2024-4-4_6-50-24.png

    then the "postings" tab. At the bottom of that page will be a link to "find all threads by. [your avatar name]".
     
  15. MrPete

    MrPete Active Member

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    I highly recommend and second @ASRDogman suggestion:
    My ASE-certified mechanic friend WAS going to help me do a rebuild ourselves, until we learned about Hybrid Pit. Not only did we use them... it was well worth it to drive all the way to SoCal and have them do the swap. That way one highly experienced shop is responsible for the entire job. And it wasn't that costly.

    Now a year in, we could not be happier. :)