Replacing bent valves

Posted by mrjsauce, Sep 21, 2011

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  1. mrjsauce

    mrjsauce Probationary Member

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    Wilmington, North Carolina
    Ok so i bought a 1990 eclipse gst for 400 dollars recenlty and obviuosly it had some issues the main one being broken timing belt and bent valves, i gues my question is are there a certain brand or type of valves i should replace them with and what kind of difference they can make with my performance.
     

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  2. JusMX141

    JusMX141 Moderator

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    If only the intake valves are bent you can get away with just swapping the valves- if you have bent exhaust valves, it's highly recommended that you replace the guides as well. The exhaust valves are much stronger than the intake valves so when they contact the piston there is a tendency to do guide damage that may go unnoticed until you've already assembled the engine.

    Using OEM replacement parts are fine.
     
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  3. g4ebguy90

    g4ebguy90 Proven Member

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    Rockford, Illinois
    You can pick up a used head, cheaper then probaly buying all the parts, and paying labor to fix the one you got.

    I usually sell good condition heads with all valves springs etc etc, for around $100 on average.

    Valves usually cost $10.00 each. Not including labor to remove and install.
     
  4. mrjsauce

    mrjsauce Probationary Member

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    i do beleive i have bent exhaust valves im not looking at it right now so idk for sure but i am going to double check. thanks for the input and i probably will just go with oem.

    thanks g4 that seems like a good idea seeing as all the quotes ive got on fixing it are much higher than $100, roughly how much does shippin usually run. i live in NC
     
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  5. g4ebguy90

    g4ebguy90 Proven Member

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    Please private message me. Thanks.
     
  6. coop795

    coop795 Proven Member

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    Meridian, Idaho
    when you take the head off you need to check the pistons, if you smacked them you should replace them. we run boost and they will break if they are cracked.
     
  7. g4ebguy90

    g4ebguy90 Proven Member

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    Turbo pistons are actually quite strong. If you have ever had one out of the engine. They are quite beefy. I have dropped a couple before... crappy ones, like 4 feet onto concrete, the tops might get a scratch, the sides might dent in a bit, but they are pretty tough.

    As long as the valves were just bent, not broken or sunk into the head itself, like embedded then I wouldn't worry about the pistons to much.
     
  8. mrjsauce

    mrjsauce Probationary Member

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    The pistons look fine they didnt get smacked too bad
     
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  9. g4ebguy90

    g4ebguy90 Proven Member

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    Hey I did send you a private message. Look in the top right corner of the webpage. You will see the option to click on it. Should be a flashing notification.
     
  10. ontario AWD

    ontario AWD Proven Member

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    North Bay, ON, Canada
    Make sure you take a light and check the bottom of every guide that had a bent valve.Most will have hairline cracks that if you tweak on a little bit will break away.Not good to have floating around in your cc.
     
  11. fbc-eclipse

    fbc-eclipse Proven Member

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    denver, Colorado
    i would recommend a full head rebuilt, do it once and save money.
     
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  12. bryanwheat

    bryanwheat DSM Wiseman

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    Columbia, Missouri
    This could probably mean ten different things depending on which machinist you talk to. Some might consider just a clean and a valve grind a rebuild, some might consider new guides, new seats, new valves a rebuild. The best way to go about head work is to repair what is damaged and out of spec in this case it is the valves and most likely the guides. You would replaced the cracked guides, check the rest for internal diameter. Freshen up the seats. Freshen up the valves, lap them to the seats, surface, clean and assemble.
     
  13. iugrad92turbo

    iugrad92turbo Proven Member

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    Kalamazoo, Michigan
    Oem ones are just fine, which ever shop you go to they will look at it and see what needs to be done, i work closely with my machinist but, if your goals are stock you should be fine with oem valves.
     
    My DSM:
    1991 Eagle Talon TSi (sold)

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