Please note this thread has been inactive for 90 days. For the best results, please start a new thread.
Results 1 to 3 of 3
  1. #1

    Default 1975 25hp johnson outboard

    I recently bought a boat that has a 1975 25hp johnson outboard motor. Put in the water, cranked right up. Tried to go full throttle and it sounded like it skiped a gear and went back to mid throttle and it did this everytime I tried to go full throttle. I took apart the lower unit today just to check out everything and everything seem to be fine besides the oil in the lower unit was carmel color. Im not very experienced with boat motors or have ever done anything to a boat motor. Any advice please try to break it down where Ill understand. also should I clean the carb? I took the top spark plug out and it seemed dry. Thanks!!

  2. #2
    Rear Admiral
    Join Date
    Sep 2003
    Location
    LaPorte City, Iowa
    Posts
    4,445

    Default Re: 1975 25hp johnson outboard

    Sound's more like an ignition problem where the engine is dropping spark to one cylinder.

  3. #3
    Rear Admiral Howard Sterndrive's Avatar
    Join Date
    Nov 2008
    Location
    Kawarthas
    Posts
    4,216

    Default Re: 1975 25hp johnson outboard

    start with a compression test.
    then test spark
    Baba-buoy.

Similar Threads

  1. 1975 25hp johnson
    By 86wellcraft140 in forum Johnson & Evinrude Outboards
    Replies: 2
    Last Post: June 3rd, 2010, 06:34 PM
  2. 1975 Johnson 25hp
    By txfirefighter45 in forum Johnson & Evinrude Outboards
    Replies: 3
    Last Post: May 16th, 2009, 08:47 AM
  3. 1975 Johnson 25hp outboard need forward gear bearing and clutch
    By bigbennett42 in forum Johnson & Evinrude Outboards
    Replies: 3
    Last Post: December 10th, 2008, 11:08 AM
  4. 1975 25hp johnson
    By oscar460 in forum Johnson & Evinrude Outboards
    Replies: 2
    Last Post: September 5th, 2004, 11:09 AM
  5. 1975 Chrysler 25hp outboard wiring diagram
    By Scott Mullins in forum Force & Chrysler Outboards
    Replies: 7
    Last Post: August 8th, 2003, 08:40 PM
  1. iboats Forum Directory - Over 100,000 forum posts organized by topic