Easier to swap in a used engine or do a head gasket replacement?

Discussion in 'Gen 3 Prius Technical Discussion' started by weapon, Jul 9, 2026 at 9:37 AM.

  1. weapon

    weapon Junior Member

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    Looks so simple to swap in a used engine vs the head gasket.

    Am I correct?

    What are some of the pitfalls of a swap?
     
    #1 weapon, Jul 9, 2026 at 9:37 AM
  2. JC91006

    JC91006 Senior Member

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    a pitfall would be the used engine you put in will have more problems than the one you're replacing. But since you have a 2010, considered the worse engine year for 3rd generation, it probably would benefit you more than the potential pitfall to swap engine
     
    #2 JC91006, Jul 9, 2026 at 10:44 AM
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  3. weapon

    weapon Junior Member

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    Yes that is a major concern I do have right off the bat. I have been watching the head gasket replacement videos and it seems really labor intensive and lots of places for user errors if not careful.

    When I did the manifold/egr swap, I was looking at the engine and it seemed like a relatively simple engine swap. It just seems to be a very well enclosed process. I would for sure try to get a low milage 2015 replacement.
     
    #3 weapon, Jul 9, 2026 at 10:51 AM
  4. ASRDogman

    ASRDogman Senior Member

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    How many miles do you have on the engine? Is it burning oil?
    Replacing the head gasket is less expensive. As long as the head is not warped.
    Did the engine overheat? If you are replacing it because it JUST started leaking, you're likely okay.

    Replacing the engine is not really a "hard" job, just a lot of steps. If you go slow and take your time,
    you'll be able to do it if you have the ability.

    But putting a used engine in, is risky. Do you KNOW it's from a 2015? Do you KNOW if the mileage is
    actually the REAL miles. How well do you trust the people you'll getting the engine from?

    It would be best to get a remanufactured engine.

     
    #4 ASRDogman, Jul 9, 2026 at 11:48 AM
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