Hotter Plugs??

Discussion in 'Bubba's Outboards' started by Quackshutr, Jul 1, 2009.

  1. Quackshutr

    Quackshutr New Member

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    133
    State:
    Oklahoma, Collinsville
    If I went with a hotter plug on my 20 hp Merc..... what is the pro's and con's for doing such?
    I don't want to burn it up but was wondering if a hotter plug would burn the fuel/oil mix better, start easier etc etc.

    Give me some feed back guys..........still new to this boating stuff.

    Q
     
  2. tyrupp

    tyrupp New Member

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    306
    State:
    Ellis,Kans
    That's a good way to burn a hole in a piston
     

  3. Bobpaul

    Bobpaul New Member

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    What he said!!

    I explained a long time ago about what hot and cold plugs do. Hot plugs keep the cylinder temps up, cold plugs transfer heat to the water jacket more efficiantly to keep the heads cooler.

    Heat is the enemy to outboards:cool2:
     
  4. Bobpaul

    Bobpaul New Member

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    3,039
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    No offense to you either Ace, but that's not how the representative from Champion spark plugs explained it to me.

    It's all in the insulator and how deep or shallow it is. Such as a surface gap plug, with the insulator right there at the spark. Heat transfer is imediate to the side walls and water jacket. Results, a cooler head temp/cold plug.

    If you knew anything about an older 2 stroke, you'd know that a complete burn and no carbon build up, was not how they were designed to run.

    But ya'll carry on and believe what you want.:wink:
     
  5. tyrupp

    tyrupp New Member

    Messages:
    306
    State:
    Ellis,Kans
    Bobpaul has been giving good advice for a long time.

    Ace says it most likely won't hurt your motor

    I say don't do it, I'm not very good at paddling, that is what it will lead to.

    Bubbacat, give us the fact, according to Hoyle
     
  6. dafin

    dafin New Member

    Messages:
    1,461
    State:
    Manhattan,Kan
    I have been a mechanic for 40 years , gm service manager for close to 20 years and Bob is right . People have the idea that a hotter plug has a hotter spark when in fact it don't , it is how much heat they move to the water jacket.A hotter plug May not cause a problem , but it won't make a motor run better.
     
  7. dafin

    dafin New Member

    Messages:
    1,461
    State:
    Manhattan,Kan
    here is a picture of what the heat range does,No one said it would change the overall temp of the motor, it does change the temp of the tip of the plug . If the spark plug gets too hot, it could ignite the fuel before the spark fires; this can burn a hole in a piston. so it is important to stick with the right type of plug.
     

    Attached Files:

  8. Bobpaul

    Bobpaul New Member

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    3,039
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    You asked for it Ace: Google search and the first site was an NGK site. Guess what? It sides with me. See for yourself.

    http://www.ngksparkplugs.com/techinfo/spark_plugs/techtips.asp

    When you open the page, be sure to read the info at the bottom. It'll tickle you.

    Ever thought about changing your name to "Deuce":smile2:
     
  9. Bobpaul

    Bobpaul New Member

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    Taken directly from the site posted.

    It's important to remember spark plugs do not create heat, they only remove heat. The spark plug works as a heat exchanger
    by pulling unwanted thermal energy away from the combustion chamber, and transferring the heat to the engine's cooling
    system. The heat range is defined as a plug's ability to
    dissipate heat.

    The rate of heat transfer is determined by:

    The insulator nose length
    Gas volume around the insulator nose
    The materials/construction of the center electrode and porcelain insulator

    You're having a difficult time with reading comprehension:wink:

    You've gotta be a democrat:smile2:

    BTW, I never mentioned it had any effect on "ENGINE TEMPERATURE", They do, however effect cylinder head temp.
     
  10. brownie525

    brownie525 New Member

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    1,505
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    a hotter plug holds the heat in the tip and doesn't transfer it to the cooling system like a cooler plug would. A cooler plug is able to run cooler because it dissipates more heat into the cooling system.
     
  11. Bobpaul

    Bobpaul New Member

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    That's right. Now, why does a hotter plug not dissipate the heat?

    C'mon, you can get this one right also:wink:
     
  12. Iowa_Josh

    Iowa_Josh New Member

    Messages:
    1,463
    State:
    Central Iowa
    When do you need a hotter type plug? When there's black oily gunk on the plug, right?
     
  13. brownie525

    brownie525 New Member

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    1,505
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    Nj
    a hot plug has a longer insulator. The insulator lenght determins if its hot or a cold plug.
     
  14. brownie525

    brownie525 New Member

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    1,505
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    Nj

    yes but if you have black oily gunk on the plug you probably have something wrong.
     
  15. Bobpaul

    Bobpaul New Member

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    3,039
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  16. brownie525

    brownie525 New Member

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    1,505
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    Nj
     
  17. Quackshutr

    Quackshutr New Member

    Messages:
    133
    State:
    Oklahoma, Collinsville
    Ok guys,
    Thanks for the help and information.
    Please be cordial to each other...........we're all just trying to get out there and fish!

    :)

    Q
     
  18. AwShucks

    AwShucks New Member

    Messages:
    4,532
    State:
    Guthrie, Oklaho
    Ace, BobPaul, I for one enjoyed the information and points you guys were making. Guess, via my own experience, I have to side with BobPaul. But at least you presented the information and let us decide what was what. Thanks.