Results 1 to 15 of 15
  1. #1
    Member
    Join Date
    Jan 2017
    Location
    Moriah New York
    Posts
    77

    stripped out spark plug threads

    I have a 2006 mercury optimax with a stripped out head. My local dealer wants to put an insert in it. Should I be worried or is it a good fix?

  2. Member
    Join Date
    Jul 2004
    Location
    Penn PA
    Posts
    15,104
    #2
    Insert is fine.....don't use a wire type Heli-coil.



  3. Member
    Join Date
    Jan 2017
    Location
    Moriah New York
    Posts
    77
    #3
    Thanks I will verify that with the dealer. Is this a common problem ?

  4. Member
    Join Date
    Jul 2004
    Location
    Penn PA
    Posts
    15,104
    #4
    No....Somebody didn't know what they were doing. You are talking about sparkplug threads correct????



  5. Member
    Join Date
    Jan 2017
    Location
    Moriah New York
    Posts
    77
    #5
    Yes spark plug threads

  6. Member
    Join Date
    Jan 2014
    Location
    Ponca City, OK
    Posts
    974
    #6
    I am a master tech with Harley and have been wrenching nearly my entire life. As stated above, do not let them heli-coil the hole. The only fix I recommend for a spark plug hole is a a time-sert. If done properly it will be as good as new and will last just as long. Good luck with the fix

  7. Banned
    Join Date
    Dec 2013
    Location
    Georgia
    Posts
    2,933
    #7
    Helicoil should be just fine. Many in use. They are approved for use on piston airplane motors. Don't think an outboard motor repair is as critical.

    Timesert and other type of repair should also be just fine.

    Of course you can always replace the cylinder head to return the motor to its as new condition.

    Just a matter of how much you want to spend.

  8. Member
    Join Date
    Jul 2012
    Location
    Dale Hollow, TN
    Posts
    47
    #8
    Helicoil is not a good thread insert. I am a mechanic not marine but I don't like helicoil. They are hella trouble if they do ever mess up.

  9. Major Flagelator Gamblinman's Avatar
    Join Date
    Jun 2004
    Location
    Yantis, TX
    Posts
    4,121
    #9
    I think finding a used head would be best, and probably easiest and most efficient way.
    "Better to remain silent and be thought a fool than to speak out and remove all doubt."

  10. Member
    Join Date
    Aug 2014
    Location
    Maryland
    Posts
    1,081
    #10
    Insert is fine. It would be overly cautious to replace the head.
    Michael Martin
    Virginia...now in Maryland
    1998 P III, 2006 200 Optimax SOLD
    2017 Robalo 226 Cayman, 200 Yamaha 4 stroke

  11. Member
    Join Date
    Jan 2017
    Location
    Moriah New York
    Posts
    77
    #11
    Thanks for all the input the dealer is pulling the head and installing an insert

  12. Member
    Join Date
    Jul 2004
    Location
    Penn PA
    Posts
    15,104
    #12
    Perfect.......Make sure he replaces ALL the head bolts on that head.

  13. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
    Join Date
    Apr 2008
    Location
    Greenville, SC (US)
    Posts
    94,945
    #13
    Quote Originally Posted by Savage View Post
    Perfect.......Make sure he replaces ALL the head bolts on that head.
    +1.... 20 head bolts, and 4 seals (total).

    Actually threading for the time-sert sleeve can be challenging... many of the tools have a head that will not permit the tool to pass through the combustion chamber side of the head (due to the steep angle the plug is at).

    ANGLE is VERY critical here, also (there's not much more than a degree to play with).

    DON'T use a helicoil in this application (I personally don't use them for plugs AT ALL, due to a bad experience years ago).


    Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
    Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
    Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor

  14. Major Flagelator Gamblinman's Avatar
    Join Date
    Jun 2004
    Location
    Yantis, TX
    Posts
    4,121
    #14
    Again..a used or even new head is a no brainer here. It eliminates so many errors that could happen. New or used head, new bolts, new seals, torque wrench and 2 hours and its done..right the first time.
    "Better to remain silent and be thought a fool than to speak out and remove all doubt."

  15. Member
    Join Date
    Jan 2017
    Location
    Moriah New York
    Posts
    77
    #15
    New insert was installed .I won't be able to test run til spring. Thanks for all the input