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  1. #1
    Member
    Join Date
    Apr 2006
    Location
    Union Grove, TX
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    130

    Possible causes for cold running engine??

    The last time out I noticed it took forever for my engine to get up to operating temp, the water temp was around 70 degrees and I had to idle for about 15-20 min for it to warn up. I am going to pull the thermostats and clean if needed, but is there anything else I need to check? Poppet Valve?

  2. Kllr bee
    Join Date
    Jun 2004
    Location
    Centerpoint, Alabama
    Posts
    1,153
    #2

    Re: Possible causes for cold running engine?? (RDM0535)

    poppet.
    Richard

  3. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
    Join Date
    Apr 2008
    Location
    Greenville, SC (US)
    Posts
    94,945
    #3

    Re: Possible causes for cold running engine?? (RDM0535)

    I would check BOTH THERMOSTATS and then POPPET VALVE.

    On the poppet.... you need to ensure that the plastic poppet can slide FREELY in and out of it's grommet/seat. NO EFFORT or binding should be involved. If it's a snug fit.... there's a high potential that it will hang when you come off plane, causing a leak at low RPM's (which can induce EITHER overheating OR COLD OPERATION at idle speed... depending on the severity of the leak and the efficiency of the water pump).



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