trying to understand kawa 3 cylinder ignition system
pxctoday

» Log in

User Name:

Password:

Not a member yet?
Register Now!

» Find OEM Parts

» Jobs

» wallpapers

Results 1 to 7 of 7
  1. #1
    PWCToday Regular madtom's Avatar
    Join Date
    Apr 2018
    Location
    virginia
    Posts
    57
    Blog Entries
    1

    trying to understand kawa 3 cylinder ignition system

    So from a detailed examination of my 900 stx, the ignition system for the 3 cylinder Kawasaki PWCs looks to be a wasted spark( meaning that all 3 plugs fire when CDI sends signal) CDI system.

    I currently have no problems with the electrics other than the dead battery just trying to understand the system. I do most of the work myself and it helps to know what proper operation is supposed to be like. I bought this jet ski cheap because the previous owner let cooling system fill with sand. I literally had to disassemble everything to get all of the sand out. He said it was over heating...wonder why lol while I'm at it replacing all the seals and rebuilt the carb and switched to a premix system.


    based upon basic 2 cycle understanding I see this happening in the engine each rotation. I may have the cylinders out of order. doesn't seem to be a lot of detailed info about these motors out there. from my limited knowledge I have determined that....

    standard 2 cycle engine rotation events..... x 3

    3cylinder kawa ver 2 900stx.png
    I know the crank journals are spaced 120degrees from each other

    crank.jpg
    the kill switch and on off key switch control the power which is fed to the ignition system.




    on the flywheel there is a position marker and 3 equal length magnets positioned 120 degrees apart around the wheel

    boat1.jpg

    the stator generates the power to run the ignition system and also charges the battery. also included in this part of the engine is the sensor which provides the signal from the flywheel.

    Crank-Case-and-Full-Stator-Generator-Assembly-21003-37301-_195-a.jpg

    Ignition is potentially affected by the following inputs

    1. the air temp sensor located in the hull above the engine
    s-l1000.jpg

    2. water overtemp sensor attached to the pisser off of the exhaust riser

    IMG_0896.jpg

    Advance looks to be a programed curve which is located on a chip in the CDI..... which there seems to be zero circuit diagrams of.

    Just trying to learn.... the service manuals and supplement are limited in the theory side of the house.

    Thanks for your help.

    Thomas

  2. #2
    PWCToday.com Is My Home Away From Home WFO Speedracer's Avatar
    Join Date
    Aug 2006
    Location
    Al-ugh-bam-ugh
    Posts
    26,155

    Re: trying to understand kawa 3 cylinder ignition system

    most triples that I am aware of do not run a wasted spark system, this is why they have three lugs on the flywheel and three different coils, so they can fire at 120 degree intervals.
    Y'all know me, still the same O.G. but I been low-key
    hated on by most these &^$$@s with no cheese, no deals and no G's, no wheels and no keys, no boats, no snowmobiles, and no skis, mad at me cause I can finally afford to provide my family with groceries


  3. #3
    PWCToday Regular madtom's Avatar
    Join Date
    Apr 2018
    Location
    virginia
    Posts
    57
    Blog Entries
    1

    Re: trying to understand kawa 3 cylinder ignition system

    When i put the motor back in next week i will test it with plugs out.
    If it fires them separately then it is a programmable chip in the cdi then...

    That would make sense with the little magnet separate from the larger ones to indicate completion of a revolution.
    Last edited by madtom; 05-26-2018 at 10:05 AM.

  4. #4
    PWCToday Regular madtom's Avatar
    Join Date
    Apr 2018
    Location
    virginia
    Posts
    57
    Blog Entries
    1

    Re: trying to understand kawa 3 cylinder ignition system

    So I actually found a pretty detailed list of Kawasaki details in an old dealer education pamphlet.

    JETSKI_2001_Page_22.jpgJETSKI_2001_Page_21.jpgJETSKI_2001_Page_20.jpgJETSKI_2001_Page_19.jpgJETSKI_2001_Page_18.jpgJETSKI_2001_Page_17.jpg

  5. #5
    PWCToday.com Is My Home Away From Home Chester's Avatar
    Join Date
    Feb 2002
    Location
    Vancouver, BC Canada
    Age
    56
    Posts
    2,906

    Re: trying to understand kawa 3 cylinder ignition system

    Quote Originally Posted by madtom View Post
    When i put the motor back in next week i will test it with plugs out.
    If it fires them separately then it is a programmable chip in the cdi then...

    That would make sense with the little magnet separate from the larger ones to indicate completion of a revolution.
    Each cylinder fires separately.

    Chester
    Speed is very expensive. How fast do you want to spend?

    Stand up:
    98 SXi-Pro

    Couches:

    96 XP
    86 X2

  6. #6
    PWCToday.com Is My Home Away From Home Chester's Avatar
    Join Date
    Feb 2002
    Location
    Vancouver, BC Canada
    Age
    56
    Posts
    2,906

    Re: trying to understand kawa 3 cylinder ignition system

    Quote Originally Posted by madtom View Post
    When i put the motor back in next week i will test it with plugs out.
    If it fires them separately then it is a programmable chip in the cdi then...

    That would make sense with the little magnet separate from the larger ones to indicate completion of a revolution.
    Each cylinder fires separately.

    Chester
    Speed is very expensive. How fast do you want to spend?

    Stand up:
    98 SXi-Pro

    Couches:

    96 XP
    86 X2

  7. #7
    PWCToday.com Is My Home Away From Home WFO Speedracer's Avatar
    Join Date
    Aug 2006
    Location
    Al-ugh-bam-ugh
    Posts
    26,155

    Re: trying to understand kawa 3 cylinder ignition system

    Much ado about nothing...……………………………………...
    Y'all know me, still the same O.G. but I been low-key
    hated on by most these &^$$@s with no cheese, no deals and no G's, no wheels and no keys, no boats, no snowmobiles, and no skis, mad at me cause I can finally afford to provide my family with groceries


Thread Information

Users Browsing this Thread

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

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Powered by vBadvanced CMPS v4.2.0