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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. sam spade 2

    sam spade 2 Senior Member

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    Assuming that everything went back together properly, there probably was a lot of learning accomplished here.......even if nothing else useful was.

    Back about 1965, I took apart the top end of my 283 Chevy to "fix" an assumed clicking lifter.
    I learned a LOT......including not to sit a carb in your lap while it still has gas in it !!!

    Also learned that what appears to be obvious and a natural assumption is not always correct.

    My clicking noise turned out to be a broken fuel pump spring.
     
  2. ChapmanF

    ChapmanF Senior Member

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    There was a commencement speaker at my college who told us "in a choice between ways of doing something, pick the one that will teach you more."

    Every now and then I've had moments I'll describe it as a curse....
     
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  3. sam spade 2

    sam spade 2 Senior Member

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    But there are all KINDS of valuable things that you should learn.
    Right near the top of the list should be:
    Don't waste time and money learning something that you will never need to apply ever again.

    Good time and money management is the basis for a LOT of other learning.
     
  4. Skibob

    Skibob Senior Member

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    What if car care is the guys hobby? People spend great amounts of time on their hobbies all the time. It’s comments like that that show why you are on so many peoples ignore lists.
     
  5. sam spade 2

    sam spade 2 Senior Member

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    Yes I understand that a lot of people don't like to hear things that go against their opinions.

    And some people have a problem with reading comprehension and see fighting words when there are none.

    Their loss.
     
  6. Skibob

    Skibob Senior Member

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    The door swings both ways Sam. Plenty of posters here have told you to F-OFF. You think its all of them and not you? Perhaps you should take lessons in writing comprehension, you would be better served.
     
  7. sam spade 2

    sam spade 2 Senior Member

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    Or not.
    A reaction like that often proves that they understand what I have said PERFECTLY.
    (y)
     
  8. Zeppo Shanski

    Zeppo Shanski Active Member

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    .001 ... Seriously?
     
  9. bisco

    bisco cookie crumbler

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    wouldn't bother until .002
     
  10. Zeppo Shanski

    Zeppo Shanski Active Member

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    This would be a perfect time for Marvel Mystery Oil ... to do it's only real job ... that it does very well (cleaning rings and/or valves).

    [​IMG]
     
  11. sam spade 2

    sam spade 2 Senior Member

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    Tight valves indicate WEAR has already occurred.
    No amount of "additives" will reverse that process.
     
  12. Zeppo Shanski

    Zeppo Shanski Active Member

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    OK.









    Additives clean away carbon build-up. My only problems with valves has been with carbon build-up. I guess I spoke a little fast.
     
    #32 Zeppo Shanski, Aug 27, 2019
    Last edited: Aug 27, 2019
  13. sam spade 2

    sam spade 2 Senior Member

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    Typically the carbon "buildup" on valves does NOT really indicate any kind of a problem.......despite what "shake oil" companies would have you believe.
     
  14. SFO

    SFO Senior Member

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    Wish you could've documented, or shared your journey here for those that will come after you.

    Any residual tricks of the trade that are worth imparting on the rest of us?
     
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  15. Zeppo Shanski

    Zeppo Shanski Active Member

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    Carbon build-up affects the way air enters the combustion chamber, causing many symptoms, including but not limited to: misfiring, rough running, hard starting, and poor fuel economy. Worse yet, the likelihood of a burnt valve is drastically increased.




    But then again ... I could be wrong. ... And I'm sure you're gonna tell me.
     
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  16. sam spade 2

    sam spade 2 Senior Member

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    Yes you are totally wrong.

    Carbon on the FACE of a valve has almost no impact on the incoming air flow, since that happens around the seat on the edges.

    And valves "burn" because they don't seat right.....and for carbon deposits to cause that, it would have to be REALLY BAD.
    Unless there is another long term obvious problem that you have been ignoring, there will never be that kind of carbon in the combustion chamber of a modern engine.

    Marketing is 95% lies.
    The 5% is when they make a mistake and accidentally tell the truth.

    But if it makes you feel good to dump "snake oil" into your engine, then go right ahead.
    The odds are about 50/50 that it will CAUSE more trouble than it fixes though.
     
  17. Skibob

    Skibob Senior Member

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    Use the ignore feature under his name and that all goes away.
     
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  18. ChapmanF

    ChapmanF Senior Member

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    Oh man ... you don't bring Open Sans 22 point to a font fight.

    edit ... this post can now be a perpetual little puzzle in memory of the now-vanished post that inspired it...
     
    #38 ChapmanF, Aug 29, 2019
    Last edited: Aug 29, 2019
  19. Frogblast

    Frogblast Junior Member

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    Since you were in there to do the adjustment: do you really need the SST that the manual says is needed to loosen up the camshaft / camshaft gear? Or is there another more readily available tool that gets the job done?
     
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  20. edthefox5

    edthefox5 Senior Member

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    Just curious not understanding this but how do the valves get tighter with wear?

    No hydraulic lifters.

    The fixed shims or buckets wear out thereby loosening the contact with the cam lobe thereby creating more valve tick. Cam lobe wears then less contact more clearance. All contact has greater clearance then.

    How do I get less clearance with wear?