Please note this thread has been inactive for 90 days. For the best results, please start a new thread.
Results 1 to 5 of 5
  1. #1
    Seaman chicubs08's Avatar
    Join Date
    May 2008
    Location
    Chicago,IL
    Posts
    71

    Default Merc Carb Adjustment ?

    I have a Mercruiser 140 3.0L, 4 Cylinder. With a Merc carb 2 barrel. How do i adjust the carb? I took it out this pastweek to the river. The engine was kind of hard to start. i had to hold the choke flap wide open in order for it to start. When i accelerated the engine would back fire. I have to accelerate slowly in order to get up to speed. How do i adjust the carb? or is it something else? The carb was recently rebuild.
    1984 19' Rinker w/ a Mercruiser 140 ,3.0L , 4 Cylinder

  2. #2
    Seaman chicubs08's Avatar
    Join Date
    May 2008
    Location
    Chicago,IL
    Posts
    71

    Default Re: Merc Carb Adjustment ?

    anybody that can help me out? Thanks.
    1984 19' Rinker w/ a Mercruiser 140 ,3.0L , 4 Cylinder

  3. #3

    Default Re: Merc Carb Adjustment ?

    How long has it been since you did a tune-up(spark plugs, wires, cap and rotor)?

  4. #4
    Seaman chicubs08's Avatar
    Join Date
    May 2008
    Location
    Chicago,IL
    Posts
    71

    Default Re: Merc Carb Adjustment ?

    I just did it about 1 month ago.
    1984 19' Rinker w/ a Mercruiser 140 ,3.0L , 4 Cylinder

  5. #5
    Lieutenant Commander fat fanny's Avatar
    Join Date
    Feb 2006
    Location
    Alliance, Ohio
    Posts
    1,930

    Default Re: Merc Carb Adjustment ?

    If you have an electric choke make sure the face plate mark is lined up withthe 1st mark to the right on the choke housing and start from there with the butterfly fully closed (by hand and with throttle cable diconnected) there should be a .080 gap between the throut and the butterlfy if not adjust the accelerator pump rod by tweeking it with plyers. Also make sure that your idle mixture screw is @about 1 1/4 turn out from from being seated. If thats not it check your anti siphon valve and filters. Or you could always go to the stickies adults only @ the top of this forum and download the manual to you engine or use some of the helpfull tips in that section as well. Good lucl!
    1996 Searay 175 Five Series
    3.0LX ser #F553706
    Alpha1Gen2 ser #OF530668
    1998 Chevy1/2 tonW/T
    "faster dad faster" my baby girl in the tube

Similar Threads

  1. 25hp 2 stroke merc, Carb adjustment
    By captenc in forum Mercury & Mariner Outboards
    Replies: 10
    Last Post: March 9th, 2011, 04:01 PM
  2. 95 Merc 5.0LX Carb adjustment procedure?
    By Stinky_1 in forum Mercury & Mariner Outboards
    Replies: 1
    Last Post: July 13th, 2008, 06:40 PM
  3. carb adjustment, 40hp o/b merc, i messed it up bad
    By lklansing in forum Mercury & Mariner Outboards
    Replies: 6
    Last Post: July 4th, 2006, 01:31 PM
  4. carb adjustment on 87 xr2 150 merc?
    By blackhawks21 in forum Mercury & Mariner Outboards
    Replies: 6
    Last Post: June 16th, 2006, 04:33 AM
  5. carb adjustment on 1963 Merc 110 9.8
    By gtmerrick in forum Mercury & Mariner Outboards
    Replies: 3
    Last Post: September 11th, 2005, 05:18 AM
  1. iboats Forum Directory - Over 100,000 forum posts organized by topic