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Valve stem carbon build up?

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  • Valve stem carbon build up?

    Engine is off the car- obviously had been running very rich. Supposed 54,000 miles or so but has been apart re-sealed with new rings but original bearings (guy said they were perfectly fine but I'll be pulling the pan for sure.) I never got any explanation as to why the engine had been apart at 54,000 (partially a language issue- japanese is not my first) but at the price it didn't matter too much.

    So based on the pic ....

    1. What do you figure is the cause- I'd guess running rich for a long time. Could be valve stems?

    2. How severe is this buildup? Uncommonly so?

    3. Rectification obviously pulling the head apart would be the best solution however I plan on running the unit as is for a test period (this will be going into a 2002) as I will likely want to pull it again anyway to clear up a few details. I could
    a. close the valves and soak the stems cylinder by cylinder and flush the area out

    b. get the engine in and try water injection or seafoam type stuff- not sure how well this would work outside of the combustion chamber.

    c. get the freakin thing into the car adn run the hell out of it- the most appealing option


  • #2
    Originally posted by peteinjapan View Post
    c. get the freakin thing into the car adn run the hell out of it- the most appealing option


    Works for me!

    Sport Evo No.47

    My Sport Evo Restoration


    • #3
      looks like most of the motors I have pulled apart. I vote for option C..
      Last edited by M3 Adjuster; 02-01-2008, 04:10 PM.
      Mark Williams
      Dallas, TX

      Nothing says "welcome to the neighborhood" like a search... oh wait... looks like they are all gone! :rastajake:



      • #4
        C it will be!


        • #5
          Since the engine is out of the car right?
          I'd would clean as much of the carbon off by spraying with carb cleaner (both ex and intake sides).

          Then make sure you run Chevron gas (btw all their gas grades have detergent now) or Mobil1 Super Unl. through the car when you get the engine back in the car.

          It could be the previous owner ran gas without detergent which caused the build up. Running rich would also contribute.


          - - - - - - - - - - - - - - - - - - - - - - - - - AUTOMERGED! There's no thread "bumping" or "double posting" within a 24hr period. - - - - - - - - - - - - - - - - - - - - - - -

          Ooops didn't realize you were in Japan, you probably don't get Chevron gas there. Run gas with detergent additives when you get the engine back in the car.
          Last edited by m3pat2; 02-02-2008, 05:36 PM. Reason: Automerged Doublepost