EHO35 Carbon build-up, what's normal?

Discussion in '4-Stroke Engines' started by Happy Valley, Sep 8, 2008.

  1. Happy Valley

    Happy Valley Active Member

    Pulled the spark plug to have a look yesterday and the color looks good so then put a spot light into the cylinder. I can see a flaky maybe 1 mm carbon build-up on the top of the piston. This engine has less than 10 hours on it. Is that normal, how clean should a 4 stroke piston top be?

  2. Mountainman

    Mountainman Active Member

    HappyV -- no - that doesn't sound very normal for a new 4 stroke
    even old ones I have torn down - look fairly clean - little deposit

    question comes to mind - how could it build up that fast ?

    unless you wish to pull the head and clean at this time

    think that I would just ride it - check it again in 10 to 30 hours

    I don't know why - but - I think that it will clean itself up

    hope that's not wishful thinking

    Ride That Thing - Mountainman
  3. I am just guessing here, but when you get a new engine do they run a "break in" oil at first for a certain amount of hours? Are you using a quality oil with the correct weight and rating?