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Intake valves .001" too tight - worth adjusting?

Discussion in 'Gen 2 Prius Technical Discussion' started by jeremy3s, Aug 17, 2019.

  1. Mendel Leisk

    Mendel Leisk Senior Member

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    I never saw less clearance, always more. But I think the idea is that valve seats wear; the valves are able to ride higher.
     
    edthefox5 likes this.
  2. edthefox5

    edthefox5 Senior Member

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    But valve seat wear means the valves are going deeper into the head which is more clearance on the shims.

    Never heard of my valves are tight from wear.
     
  3. Mendel Leisk

    Mendel Leisk Senior Member

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    As the seats wear the valves would rise, valve stem tips would be higher? Again, in practice I've never had this happen.
     
  4. sam spade 2

    sam spade 2 Senior Member

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    When the valve seat and matching face actually wears.
     
  5. sam spade 2

    sam spade 2 Senior Member

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    No it is NOT.
    Once again, you aren't thinking straight.
     
  6. Mendel Leisk

    Mendel Leisk Senior Member

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    Maybe a visual aid would help:

    upload_2019-11-24_10-44-52.png

    Spring is constantly trying to pull the valve up. What stops it is the valve seating against the port opening. As the valve and/or seat wear, the valve moves up.
     
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  7. sam spade 2

    sam spade 2 Senior Member

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    Tighter against the cam or rocker arm......which is not shown in the diagram.