pxctoday

» Log in

User Name:

Password:

Not a member yet?
Register Now!

» Find OEM Parts

» Jobs

» wallpapers

Page 1 of 3 123 LastLast
Results 1 to 10 of 28
  1. #1
    PWCToday Guru E350's Avatar
    Join Date
    Jul 2015
    Location
    Sacramento Delta, CA
    Posts
    392

    What could be the causes of these symptoms?

    So, I was riding the '88 X2 650cc this afternoon WOT and it was doing what I have been complaining about, mainly it loses rpms when I pull the throttle the last 1/8 or so to the throttle stop (so I back off on the throttle some and the rpm's increase).

    Then all of a sudden, wham the ski loses power and I almost go over bars, so I kill it. And feel in the intake grate for debris and there is none. Start back up and it starts fine but dies if I try to accelerate at all.

    I just did a compression test. Spot on: 160psi - 160psi (both cylinders)

    Spinning the engine with the starter reveals no bangy-bangy noises, rather it spins smooth as silk.

    (In another thread, I am asking for advice on how to do a leak down test.)

    Is this a piston port motor? How can I tell?

    Is this a reed motor? How can I tell?

    What are the symptoms when you blow up a reed?
    Learning Slowly...

  2. #2
    PWCToday Guru E350's Avatar
    Join Date
    Jul 2015
    Location
    Sacramento Delta, CA
    Posts
    392

    Re: What could be the causes of these symptoms?

    OK, I found the manual online. Under engine specifications it says:

    "2-stroke, vertical twin, piston reed valve,
    water cooled
    635 mL"

    So it is a reed valve. The spark plugs are fuel or oil fouled. I will put new ones in tomorrow and fire it up.

    And I will read about reeds...
    Learning Slowly...

  3. #3
    Top Dog hooka-2's Avatar
    Join Date
    Nov 2005
    Location
    sebring florida
    Posts
    1,855

    Re: What could be the causes of these symptoms?

    The 650 kawasaki is a reed motor. Not a piston port. What you are experiencing is probable a lean seizure. You need to clean your carb and check your high jet settings. Sounds like your running lean
    90 X2 (750), 92 X2 (750), 93 X2 (750),93 X2 (750), 99 Ultra 150(sold) 1995 Waveblaster 1

  4. #4
    PWCToday Guru E350's Avatar
    Join Date
    Jul 2015
    Location
    Sacramento Delta, CA
    Posts
    392

    Re: What could be the causes of these symptoms?

    Quote Originally Posted by hooka-2 View Post
    The 650 kawasaki is a reed motor. Not a piston port. What you are experiencing is probable a lean seizure. You need to clean your carb and check your high jet settings. Sounds like your running lean
    Quote Originally Posted by Myself View Post
    I've had 2 different Keihin CDK carbs do this in the past. No amount of cleaning or adjustment would straighten them out. They were obviously running out of fuel but would only do it after a wot run. I used a different carb on each and solved the problem. I strongly believe they had developed a hairline crack somewhere in the carb body that could actually pull air in. Add a piece of clear tubing just before the carb and run it strapped to the trailer to just make sure you're not sucking air into the fuel supply through the switch or pickup assembly.
    Thanks guys, here's some more info for you:

    1. Carb is a SBN 44 (not the Keihin diaphragm type 28 mm venturi which is specified in the manual)

    2. Here is what the BR8ES (2411) spark plugs looked like when I pulled them last evening:

    Attachment 530585Attachment 530586

    3. The failure was catastrophic in that the ski lost power immediately at WOT straight run almost throwing me over the handle bars. It would start but would not accelerate. Same thing on trailer at home after towing back with the 550sx.

    4. Put in new BR8ES (2411) spark plugs this morning, and the ski runs as usual now while on the trailer.

    5. Will put it in the water today to see if it operates as usual or is still screwed up like yesterday.

    I am new to this stuff, but I think the sudden loss of power was due to one spark plug losing spark. Which could be because of fouling. Or because of broken/breaking spark plug (high tension) wire from coil. Can I hold and wiggle the spark plug wires while the ski is running or do I risk getting a big dose of injury causing volts?
    Attached Images Attached Images
    Last edited by E350; 09-17-2017 at 03:41 PM.
    Learning Slowly...

  5. #5
    PWCToday.com Is My Home Away From Home wmazz's Avatar
    Join Date
    Jul 2013
    Location
    Riverside, CA
    Age
    57
    Posts
    2,339
    Blog Entries
    6

    Re: What could be the causes of these symptoms?

    Must have hit the wrong button. I don't know where my other post went?

    That spark plug has either water or fuel inside the spark gap. Either
    would cause your problem.


    Bill M.
    Last edited by wmazz; 09-18-2017 at 12:07 AM.
    Horsepower == Speed, RPM != Speed



  6. #6
    PWCToday Guru E350's Avatar
    Join Date
    Jul 2015
    Location
    Sacramento Delta, CA
    Posts
    392

    Re: What could be the causes of these symptoms?

    I put new spark plugs in this morning and started the x2 on the trailer for 30-45 seconds and it seemed much better. Like two cylinders were firing not just one.

    Took the x2 to the river this afternoon. Kept the bow and stern pinned and backed the trailer in deeper than I normally do. Started right up but at first it seemed like it didn't want to accelerate, then something "popped." Then it ran like a raging bull. Dropped the x2 and the 550sx into the river and parked the trailer and my wife and I road for an hour. Not one problem occurred with the x2. In fact, it ran better with the new (non-fouled) spark plugs. When we got home this evening I pulled the spark plugs and photographed them. Here they are:
    DSC03677- lq.jpgDSC03679- lq.jpg

    One more thing, after the ski ran so well on the trailer, I added one-half of a container of Red Line Complete Fuel System Cleaner Powersports:

    https://www.amazon.com/Red-Line-Comp.../dp/B0041CFZ94
    Last edited by E350; 09-18-2017 at 12:18 AM.
    Learning Slowly...

  7. #7
    I dream skis
    Join Date
    Jan 2007
    Location
    Earth (but just visiting)
    Posts
    527
    Blog Entries
    1

    Re: What could be the causes of these symptoms?

    Any particular reason you went to non-resistor plugs?

  8. #8
    PWCToday.com Is My Home Away From Home hyosung's Avatar
    Join Date
    Aug 2010
    Location
    Australia
    Posts
    8,218

    Re: What could be the causes of these symptoms?

    that plug reading is un usable . you need to do what is called a plug chop > ride WOT and kill the motor whilst still @full throttle , find a safe area where you can go for a good 40 second WOT run that is close to an area where you can walk or float to a beaching area , then pull the plugs and take a pic "then we can see whats going on,
    2 x 650 sx custom build (my toys) http://www.pwctoday.com/showthread.php?t=425767

    modded X2 650

    stock looking ZXI 900 ""being cannibalized to sponsor a 650 sx build """

    Jerry Rigging is my specialty .....


    Originally Posted by hyosung
    so when you say i """ hammer and slap things together """ this may be so , BUT they are hammered and slapped together SOLID

  9. #9
    PWCToday.com Is My Home Away From Home Rushford_Ripper's Avatar
    Join Date
    Dec 2009
    Location
    Buffalo
    Age
    30
    Posts
    5,535

    Re: What could be the causes of these symptoms?

    Funny thing is my x-2 did the same thing this weekend. Ran great, next day like crap, changed plugs and ripped all day no problem.


  10. #10
    PWCToday Guru E350's Avatar
    Join Date
    Jul 2015
    Location
    Sacramento Delta, CA
    Posts
    392

    Re: What could be the causes of these symptoms?

    Quote Originally Posted by ericstratton View Post
    Any particular reason you went to non-resistor plugs?
    ericstratton: Good catch. So I just looked up the spark plug specification in the Owner's Manual, and lo and behold, although apparently a resistor or a non-resistor is acceptable (at least in the '88 Owner's Manual), I am apparently running too hot of a plug by running the B8ES:

    Spark Plug: NGK BR7ES NGK B7ES

    I think I may put in some BR7ES or B7ES and see what the difference is.

    As far as resistor vs non-resistor type plugs, I am curious about that too. What is your experience, understanding or thoughts on the difference in our engines. I simply do not know.

    hyosung: Salmon and Striped Bass are running right now, with a lot of fisherman on the banks, so for now I likely cannot get close enough to shore to do the spark plug test you describe.
    Last edited by E350; 09-18-2017 at 11:06 AM.
    Learning Slowly...

Page 1 of 3 123 LastLast

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