Results 1 to 5 of 5
  1. #1

    Join Date
    Feb 2008
    Location
    No. MN
    Posts
    320

    MSX 140 Compression Rating

    What should it be cold? I have 120, 100, and 90. Thinking I need some rings.


  2. #2
    Click avatar for tech links/info, donation request K447's Avatar
    Join Date
    Jul 2007
    Location
    near Toronto, Canada
    Posts
    36,595
    +1
    1,276
    Compression should be 120PSI or higher, the other two seem very low.

    Exact numbers will vary depending on the gauge, the battery, cold vs. warm engine, etc.

  3. #3
    ph2ocraft's Avatar
    Join Date
    Apr 2006
    Location
    Campbell, Ca.
    Posts
    14,100
    +1
    105
    I'd check the compression again and maybe this time mix it up and see if your compression readings are weak battery induced??

    Which cylinder is the lowest after a couple compression readings, the MAG?

  4. #4
    Race, wreck, repeat delagem's Avatar
    Join Date
    Aug 2006
    Location
    Homer, NY
    Posts
    728
    +1
    2
    Read the below article:

    http://www.groupk.com/tec-comp.htm

    I was very worried about my compression readings, done with a crappy compression gauge. The readings were low, and actually varied on the same cylinder on back to back testing. Then I threw out that old gauge, and used a nice SnapOn gauge, got 124psi across the board on repeated testing.

    I would say mine is an average engine, not hi or low hours, not particularly well maintained, and ridden in salt water.....

    So, short answer, check with a better gauge before you tear into that engine!

  5. #5

    Join Date
    Feb 2008
    Location
    No. MN
    Posts
    320
    90 on the middle, 100 on the PTO. The mag. burn't last year so it is new. I will check with another gauge. Battery is strong.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Replies: 54
    Last Post: 09-29-2014, 09:32 PM
  2. Replies: 27
    Last Post: 03-06-2014, 12:56 AM
  3. rear cyl.low compression msx 140
    By g3nautica in forum Polaris How To & FAQs
    Replies: 1
    Last Post: 06-10-2009, 02:35 AM
  4. Msx 140 Alert!!!
    By wetherby in forum Polaris Open Discussion
    Replies: 1
    Last Post: 08-28-2006, 12:27 AM
  5. MSX 140 - Should I buy it for 7K?
    By X-Cane in forum Sea Doo Open Discussion
    Replies: 10
    Last Post: 04-23-2006, 11:12 AM

Posting Permissions

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