Painting a Happy Times engine, cause overheating?

Discussion in 'Painting, Welding, Bending and Gas Tanks' started by AndrewAnonymous, Jun 20, 2008.

  1. AndrewAnonymous

    AndrewAnonymous New Member

    I'm hoping to paint my 70cc HT motor with some high temp engine paint. I've been warned this may harm the motors ability to disapate heat and deminish its life. I'm interested to hear if overheating or premature wear has been an issue for any of you with painted engines. :?:

  2. datz510

    datz510 Member

    I painted mine with high-temp flat black engine block paint. No overheating problems yet, and I've been riding in 115F temps lately here in Arizona!!!! The paint is holding up really well too. Also with the flat black, it makes the engine a little less noticeable.
    Last edited: Jun 20, 2008
  3. BSA

    BSA Guest

    Logic would dictate that painting an engine black would improve the cooling, as black is an excellent absorber for heat and thus an excellent emiter of heat.

  4. will_start

    will_start Member

    i painted mine with black high temp paint about four months ago and it matches the
    general grime, also made any oil or petrol stains blend right in.

    I've read other posts saying it won't cause harm.
    I would search and post 'em if i could be bothered,

    "they're here somewhere !!"
  5. Anything with a dark color is going to attract heat . just walk on the black side walk in bare feet while sun is beating down on it to figure this out.

    It may raise the temp on the small two stoke beating in the sun some but I wouldn't think enough to effect performance or make it over heat.

    Plus One of the biggest sellers right now are the black motor kits from the factory.

    Many are installed and running fine.


  6. AndrewAnonymous

    AndrewAnonymous New Member

    Thanks for the replies. I tried a search but I couldn't turn up anything useful, perhaps I just wasn't using the right terms.

    I think I'll be painting mine, and if it wears out a few miles earlier then it would have otherwise, oh well.
  7. Alan

    Alan Member

    Compared to normal running engine temperature, which is fairly hot, the sun shining on it won't be a factor at all.

    And what BSA said is correct. I read it before at various sites. Sorry, no link.

    Not sure about the new black powdercoat kits. They sound like they'd hold in the heat.
  8. AndrewAnonymous

    AndrewAnonymous New Member

    Right, I'm not worried about the sunlight warming the engine. Just the extra coating reducing the heat transfer effectiveness of the cooling fins and case by adding a small layer of insulation. Metal is a great heat conductor, paint isn't. An example of this effect is with exhaust pipes, if you give the inside of the pipe a good coating of high temp paint it will prevent it from bluing up.

    edit: Black is a great for getting heat from sunlight. Is is because all color we see is reflected light. White reflects nearly all colors of light wavelengths, thus it stays cooler is sunlight. A blue object will absorb all the wavelengths but only the blue wavelengths, so it reflects blue and that's what what our eyes see. A black object will absorb the broadest range of the light spectrum reflecting little back, so it becomes warmer and retains more of the light radiant energy. I don't believe the color of the paint will effect how well it absorbs or dissipates engine heat significantly. Color only plays in role when the paint or object is heated by a light source.
    Last edited: Jun 21, 2008