User Tag List

Results 1 to 6 of 6
  1. #1
    Join Date
    Sep 2020
    Location
    Ottawa canada
    Posts
    6
    Thanks (Given)
    0
    Thanks (Received)
    0
    Likes (Given)
    0
    Likes (Received)
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    1987 mercury 60 hp piston damage




    Hello, I had a piston failure in my number 1 cylinder and I was wondering if anyone might be able to identify the root cause from seeing the piston. The engine did not seize but the metal pushed onto the plug shorted the spark killing the one cylinder. I recently had to replace the stator and timing trigger but the motor ran fine for a month before this occurred. From the picture can one tell if this was a progressive failure or does this type of failure happen quickly.
    thanks for any help.

    jumbo 3905



    Attached Thumbnails Attached Thumbnails B79B900C-0E6A-48BB-A11E-4B86D903AFFA.jpg  

  2. #2
    Join Date
    Dec 2001
    Posts
    9,503
    Thanks (Given)
    23
    Thanks (Received)
    271
    Likes (Given)
    191
    Likes (Received)
    1976
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    The old...... Mercs do that ,The piston has that high Dome that keeps the exhaust and intake seperated..It runs hot and acts like a heat sink. Low octain gas or lugging the motor will put the motor at risk. Merc cut the dones a 1/16 of an inch to help the problem and lower the timing advance. Your timing might be a bit advanced where you replaced parts. Pop a nudda piston in and sail on.Check/ retard the timing and don't lug the rpms.

  3. Likes Merc 2.5 liked this post
  4. #3
    Join Date
    Sep 2020
    Location
    Ottawa canada
    Posts
    6
    Thanks (Given)
    0
    Thanks (Received)
    0
    Likes (Given)
    0
    Likes (Received)
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Dave S View Post
    The old...... Mercs do that ,The piston has that high Dome that keeps the exhaust and intake seperated..It runs hot and acts like a heat sink. Low octain gas or lugging the motor will put the motor at risk. Merc cut the dones a 1/16 of an inch to help the problem and lower the timing advance. Your timing might be a bit advanced where you replaced parts. Pop a nudda piston in and sail on.Check/ retard the timing and don't lug the rpms.
    thanks Dave I appreciate the response, does this usually happen over time or does the piston break down rather quickly.

  5. #4
    Join Date
    Feb 2015
    Location
    Ontario
    Posts
    8,091
    Thanks (Given)
    205
    Thanks (Received)
    321
    Likes (Given)
    1921
    Likes (Received)
    2005
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    Use Shell 91 Vpower. Check all is correct with the timing and the carb.

  6. #5
    Join Date
    Feb 2009
    Location
    Edgewater,B.C. CANADA
    Posts
    8,260
    Thanks (Given)
    179
    Thanks (Received)
    321
    Likes (Given)
    3578
    Likes (Received)
    1236
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Did you do a full link and sync after installing the new parts?

    Dave
    1980 Cougar 19 tunnel,90 2.4L Bridgeport EFI in middle of restoration.
    1988 BAJA Sunsport 186, 96 225 Pro Max
    79 12' Auminum, 95 Merc 9.9
    RIP Stu
    "So many idiots, so few bullets"

  7. #6
    Join Date
    Sep 2020
    Location
    Ottawa canada
    Posts
    6
    Thanks (Given)
    0
    Thanks (Received)
    0
    Likes (Given)
    0
    Likes (Received)
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Dave Strong View Post
    Did you do a full link and sync after installing the new parts?

    Dave
    I did not do a full lync and sync I checked the timing statically at 26 BTDC which is supposed to give 21 BDTC on the water. I was told this is better for the engine over the 28 and 23 from the manual. That was the same setup before I changed the parts.

Similar Threads

  1. Mercury 2.5l retarded timing cause engine damage?
    By Rider_560 in forum Technical Discussion
    Replies: 3
    Last Post: 09-10-2018, 09:49 AM
  2. 1992 XRI piston damage
    By wakepics in forum Technical Discussion
    Replies: 6
    Last Post: 07-30-2018, 06:59 AM
  3. Mercury Tech: Cylider damage, Mercury V6
    By Droll in forum Technical Discussion
    Replies: 2
    Last Post: 07-16-2010, 09:55 PM
  4. 86' 175hp merc piston damage
    By luckybuff in forum Technical Discussion
    Replies: 2
    Last Post: 05-07-2010, 10:22 PM
  5. What caused this BP piston damage?
    By Alan Power in forum Technical Discussion
    Replies: 22
    Last Post: 09-19-2006, 08:37 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •