Please note this thread has been inactive for 90 days. For the best results, please start a new thread.
Results 1 to 4 of 4
  1. #1

    Default Hard starting 4hp Mercury

    I have a 2004 4 hp Mercury outboard on a small fishing boat that stays at the dock. When not in use, the motor is tilted up, so the lower unit is out of the water. The motor is difficult to start initially. Per the instructions, I choke it for two pulls. It will often start on the first or second pull, but then dies immediately. Per instructions, I push the choke in. It will then take anywhere from 6 to 15 pulls before it will start and continue to run. I have replaced the spark plug and set the slow and high speed carb adjustments as the owner's guide suggests. After running, it will restart easily. What should I check or replace?

  2. #2
    Vice Admiral TOHATSU GURU's Avatar
    Join Date
    Jul 2004
    Location
    TAMPA
    Posts
    5,746

    Default Re: Hard starting 4hp Mercury

    It sounds like a dirty carburetor so have it cleaned. Really cleaned, not sprayed with some fruity mechanic in a can carburetor cleaner....But, I'm intrigued by what you think you are adjusting. If you have a 2-stroke, there is an idle RPM adjustment and an air mixture screw adjustment. If you have a 4-stroke the only thing you can adjust is the idle RPM.
    Elvin
    My answers are like Zen...It may not be the answer you want, but it is generally the answer you need.

    The 3 Rules:

    1) Look in your service manual first...Then ask me if it is correct.
    2) Understand that your desire to repair your engine does not mean that you have the ability to do so.
    3) If you are confused, take your engine into a dealer..Then let them be confused...At least, in theory, they sent someone to outboard 101.

  3. #3

    Default Re: Hard starting 4hp Mercury

    This is a two cycle engine. It has a slow speed carburetor adjustment screw and an idle speed adjustment screw. I mis-spoke mentioning high speed adjustment -that is fixed. I got my motors mixed up. Nonetheless, the starting difficulty has been since the motor was new, so I don't think it was shipped with a dirty carburetor. but I will clean it off-season.

  4. #4
    Vice Admiral TOHATSU GURU's Avatar
    Join Date
    Jul 2004
    Location
    TAMPA
    Posts
    5,746

    Default Re: Hard starting 4hp Mercury

    "It has a slow speed carburetor adjustment screw" No, that is an air mixture screw.
    Elvin
    My answers are like Zen...It may not be the answer you want, but it is generally the answer you need.

    The 3 Rules:

    1) Look in your service manual first...Then ask me if it is correct.
    2) Understand that your desire to repair your engine does not mean that you have the ability to do so.
    3) If you are confused, take your engine into a dealer..Then let them be confused...At least, in theory, they sent someone to outboard 101.

Similar Threads

  1. 1977 Johnson 4HP hard starting
    By Hank007 in forum Johnson & Evinrude Outboards
    Replies: 4
    Last Post: August 15th, 2008, 10:30 PM
  2. Starting Mercury 4hp-4 stroke
    By soh_2 in forum Mercury & Mariner Outboards
    Replies: 1
    Last Post: August 12th, 2007, 02:38 PM
  3. Hard Starting Mercury 7.5
    By steam_mill in forum Mercury & Mariner Outboards
    Replies: 12
    Last Post: August 5th, 2005, 08:58 PM
  4. Hard starting 90hp mercury
    By ther2525 in forum Mercury & Mariner Outboards
    Replies: 1
    Last Post: June 12th, 2003, 05:00 PM
  5. Hard Starting Problem/ Mercury O/B
    By Fish Head in forum Mercury & Mariner Outboards
    Replies: 4
    Last Post: August 12th, 2002, 05:39 AM
  1. iboats Forum Directory - Over 100,000 forum posts organized by topic