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Exhaust valve replacement

Discussion in 'Gen 3 Prius Technical Discussion' started by donzoh1, Dec 30, 2023.

  1. donzoh1

    donzoh1 Active Member

    Joined:
    Jan 19, 2019
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    Location:
    Lenexa, KS
    Vehicle:
    2004 Prius
    Model:
    Five
    One exhaust valve was damaged when the connecting rod failed. The valve is bent. I have another gen 3 valve labeled Z I while the other valves are labeled Z. Intake valves are all labeled Z R. The Z I valve appears to match the bent Z valve but I can't measure accurately for length due to the bend. I didn't lap it yet but it already holds water with the head inverted (spring not yet installed). The car already has 230K or so on it. Is there a difference between the Z and Z I exhaust valves?
     
  2. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
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    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    I don't know about the valve parts you could just grind the stem off until it matched I would think in the ZZ engine there should not be any serious differences other than maybe diameter for whatever reason between Atkinson cycle and regular I I personally don't really know. But when all this didn't happen well you better look at the back side of your center section and the girdle really good usually that rod smacks all that mess and creates Fisher cracks in the aluminum meaning one generally places the whole center section possibly the girdle and all that making this repair quite a bit more costly than initially thought which is why a lot of times it doesn't get done so I guess you need to be looking at those pieces really close and well there are kits that use a powder and or a liquid and a spray and a black light that might help you make certain you do not have any cracks and weakness You certainly want to know this before you reassemble all this and call it done
     
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  3. donzoh1

    donzoh1 Active Member

    Joined:
    Jan 19, 2019
    434
    149
    0
    Location:
    Lenexa, KS
    Vehicle:
    2004 Prius
    Model:
    Five
    The stem matches the other seven in terms of keeper notches and length so I'm using it.
     
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