Results 1 to 10 of 10
  1. #1

    Still have the same problem with my 94 SL650

    Hi everyone, it's been a while but the last thing I was working on back then, was replacing the magneto and fly wheel to see if that would cure my problem with my 1994 SL650. It didn't, I was so fustrated that I haven't touch the thing all summer. The problem has been that the ski will run fine for about 10 - 20 minutes and then shut down. It will always start right back up, take off great, go for about 50 yards and then shut down. After my latest repair, I thought I had fix the problem. It ran for about 20 minutes, took a break and ran it for another 20 minutes and then the problem arose again. This what I have replaced or rebuilt so far over the course of about 3 or 4 years.


    Rebuilt the carbs at least 3 times, I've lost count
    Replaced OEM fuel pump with triple pumper
    Replaced fuel lines, petcock and inline filters
    Cleaned fuel tank
    Replaced magneto and fly wheel
    Battery
    Cleaned all wire connections

    My next attempt was going to replace the CDI box, thinking that it might be over heating some how. I'm stabbing in the dark here. If anyone can help me out, I wouls greatly appreciate it. This problem has been on going for several years. My on water time is very limited. April - October and the water is not convenient.


  2. #2
    Banned User
    Join Date
    Jun 2010
    Location
    Milwaukee WI
    Posts
    16,708
    +1
    1,324
    Check your fuel tank vents and check valves for proper operation.

  3. #3
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
    Join Date
    Oct 2006
    Location
    Cleveland OH
    Posts
    17,330
    +1
    31
    That's a good start ^^^^


    Have you checked to see if you have spark when it acts up?

    How about fuel?

  4. #4
    Quote Originally Posted by xlint89 View Post
    That's a good start ^^^^


    Have you checked to see if you have spark when it acts up?

    How about fuel?
    The roll over check valve has been removed. Fuel had been replaced at the beginning of the season.
    I have not checked the spark because it always strarts right back with no hesitation. Do you think I'm wasting my money on a new CDI box?

  5. #5
    Banned User
    Join Date
    Jun 2010
    Location
    Milwaukee WI
    Posts
    16,708
    +1
    1,324
    I woulc not remove those check valves. Replace them with new parts.

  6. #6
    BlueFishCrisis's Avatar
    Join Date
    Aug 2011
    Location
    Medina, Ohio, United States
    Posts
    4,988
    +1
    140
    Quote Originally Posted by RNusbaum View Post
    Quote Originally Posted by xlint89 View Post
    That's a good start ^^^^


    Have you checked to see if you have spark when it acts up?

    How about fuel?
    The roll over check valve has been removed. Fuel had been replaced at the beginning of the season.
    I have not checked the spark because it always strarts right back with no hesitation. Do you think I'm wasting my money on a new CDI box?
    What is a roll over check valve? You should have two valves on your fuel system. One lets air out when the vapors expand, one lets air in when fuel is removed. If neither are present, you can have a multitude of issues ranging from flooding of the motor to starving the motor of fuel....... If both are removed, and the lines are open to the atmosphere, you are asking for a fire ball......

  7. #7
    Quote Originally Posted by BlueFishCrisis View Post
    Quote Originally Posted by RNusbaum View Post
    Quote Originally Posted by xlint89 View Post
    That's a good start ^^^^


    Have you checked to see if you have spark when it acts up?

    How about fuel?
    The roll over check valve has been removed. Fuel had been replaced at the beginning of the season.
    I have not checked the spark because it always strarts right back with no hesitation. Do you think I'm wasting my money on a new CDI box?
    What is a roll over check valve? You should have two valves on your fuel system. One lets air out when the vapors expand, one lets air in when fuel is removed. If neither are present, you can have a multitude of issues ranging from flooding of the motor to starving the motor of fuel....... If both are removed, and the lines are open to the atmosphere, you are asking for a fire ball......
    To the best of my knowledge and correct me if I'm wrong, there are four lines coming from my fuel tank, the main line, the reserve line, a return fuel line, and a roll over check valve line or a vent line. The roll over check valve was removed by the previous owner. I am not sure if the roll over check valve is usually inside or outside the tank? The other end of the check valve line or vent line is just lying in the bottom of the ski. So the tank has no pressure build up because it has an open line.

    I believe a roll over check valve is a valve that will not allow gas to escape during a roll over but still allows air to enter the fuel tank.

    So if I understand you correctly, I have a fire ball waiting to happen. Can you tell me where these vales should be in my fuel system?
    I'll be more than happy to install new ones.
    Thanks in advance.

  8. #8
    BlueFishCrisis's Avatar
    Join Date
    Aug 2011
    Location
    Medina, Ohio, United States
    Posts
    4,988
    +1
    140
    You are correct with the fuel line routing - one main, one reserve and one return fuel line. The other if for venting purposes. Take a piece of 1/4" line about 6" from the tank and install a "T". Install a 3" piece of 1/4" line off the "T" and install an inlet vent which allows air into the tank, but not air or fuel out. Continue the line from the other side of the "T". Find a location either in front of the seat or next to the steering column under the hood where a 1/2 - 3/4" hole is drilled. There may be a rubber vent hood already installed. Install an inline check valve which is set to release at 2-3 psi +/- if pressure builds in the tank. Connect the other end of the valve to the rubber vent hood. Secure all the connections with hose clamps and zip ties as appropriate.

    IT sounds like excessive pressure build up is not an issue, but a lack of pressure build up in the tank can also affect performance. A positive pressure in the tank can help to push fuel through the system. With the vent line simply laying in the bottom of the ski, gasoline vapor, and, if the ski should tip over, raw fuel, will come out of that line with out the proper check vents installed. Kaboom.

  9. #9
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
    Join Date
    Oct 2006
    Location
    Cleveland OH
    Posts
    17,330
    +1
    31
    There were roll over shut off valves on the bottom of the old style fuel pick ups. It would stop fuel from pouring out of the vent line if it was flipped. (basically a spring loaded one-way valve)


    After re-reading the issue, how about feeling the tops of the cylinder heads right after it shuts down?

    Have you ever removed the cylinder heads?

    What's your compression?

    You may be having a siezure issue.

  10. #10
    Quote Originally Posted by xlint89 View Post
    There were roll over shut off valves on the bottom of the old style fuel pick ups. It would stop fuel from pouring out of the vent line if it was flipped. (basically a spring loaded one-way valve)


    After re-reading the issue, how about feeling the tops of the cylinder heads right after it shuts down?

    Have you ever removed the cylinder heads?

    What's your compression?

    You may be having a siezure issue.

    Thanks for the venting line information. I'll get right on it. I'm quickly running out of time to be on the water.
    The front cylinder head was removed a year ago. All was well. It has been a while since I took compression readings but I'll get on that too.
    Thanks for your input. I'll let you know.

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. GTX rfi...still the same problem
    By PhilnEdee in forum 2-Stroke Performance
    Replies: 5
    Last Post: 08-15-2008, 11:17 AM
  2. I have Ignition Problem With my Sltx Help me!
    By Vortexx972 in forum Polaris Open Discussion
    Replies: 23
    Last Post: 03-03-2008, 02:23 PM
  3. Still have a problem with my RXP.....
    By LiquidDI in forum 4-Tec Performance
    Replies: 3
    Last Post: 07-04-2006, 01:18 AM
  4. Help, having problems with my 2005 RXT, low hours
    By 05rxt in forum 4-Tec Performance
    Replies: 6
    Last Post: 04-10-2006, 11:24 PM
  5. HELP...I think I have a serious problem with the OPAS Blocks
    By Totallyblown in forum 4-Tec Performance
    Replies: 16
    Last Post: 01-01-2006, 09:39 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
  •