Page 1 of 4 1 2 3 ... LastLast
Results 1 to 10 of 31
  1. #1

    Join Date
    Mar 2014
    Location
    Austin Texas
    Posts
    56

    Sun n Sea Rio, misfiring when warm

    Hey guys, as some of you may know, I have a 2001 Sun n Sea Rio with the 1200 polaris engine in it. I just got done getting it together and comfortable that it would work out at the lake and decided today was the day, got it out there and it ran a little rough on the bottom, like a cylinder was cutting out. I took it through the rpm range to see if that changed at all and it smoothed out and got to max rpm with no issues, then after about 3/4 throttle cruising for 5-10 minutes it started misfiring all the time. I know that it has spark but it seemed somewhat weak the last time I checked it. My current thought is a bad CDI but I don't want to mess with it if there is a good chance it is something else entirely, just getting some potential things to test to pinpoint the issue.

    Thanks,
    Carl


  2. #2

    Join Date
    Mar 2014
    Location
    Austin Texas
    Posts
    56
    second, possibly unrelated issue, the buzzer comes on all the time... as it isn't something the pwc models have I am unsure how to troubleshoot it, the only times it has come on in the past were overheated or low oil and both of those cut the engine rpm's but it revs correctly now so I am lost on that as well, but that may be unrelated

  3. #3
    Click avatar for tech links/info, donation request K447's Avatar
    Join Date
    Jul 2007
    Location
    near Toronto, Canada
    Posts
    36,579
    +1
    1,272
    Trace the buzzer cause. There may be a loose connection or wire fraying somewhere that is causing a partial signal. This could affect the engine operation and the buzzer.

  4. #4
    ripcuda's Avatar
    Join Date
    May 2010
    Location
    Newman Lake, WA
    Posts
    2,389
    +1
    166
    Howdy,
    The Rio has an oil level low switch in the oil tank. This is all too often triggered when going over waves when there is less than 1/2 (?) tank of oil... even though there is plenty of oil in the huge tank. The switch is placed in such a place that if the oil sloshes, it'll trigger. When triggered, the buzzer will go off and it'll force the RPMs to drop. This happens via the CDI on the tan wire input shared with over heat sensor. Unplug the single wire to the oil tank low level switch and see if it continues to buzz at you. I removed this safety on my Rio as I am now using a different oil tank setup.

    If it continues buzzing at you... might need to unscrew the dash and inspect the rat's nest of wires under there. That's where the buzzer is located. So it now buzzes at you... but doesn't cut RPMs anymore like it used to? If so... that sounds like a CDI issue (or wiring)

    I had my CDI go bad in my Rio. I too had weak spark and occasionally zero spark (wouldn't start... but then eventually would). A new CDI cured my issues. Thankfully my stator/mag was fine.

    On our boats... there is no LR-505 start stop regulator... since we have a keyed ignition switch. So our CDIs stay constantly powered off the battery via the Red/Purple wire. I wonder if that has a negative long-term affect on the CDIs.

    Cheers!

  5. #5

    Join Date
    Mar 2014
    Location
    Austin Texas
    Posts
    56
    So, the buzzer is connected to a solid grey wire, I couldnt trace that into the box so I cant really figure out where it comes from, I have been trying to figure out what would turn on the buzzer but not cut RPM's and I cant think of anything, is there something that shows a warning but doesn't slow the ski down on a virage? my current bet is a bad cdi as almost everything else in the drivetrain has been replaced somewhat recently when a new engine was put in.

    Ripcuda, I did find out about the oil level sender once, someone had disconnected the wires but didnt bypass it, what did you do to disable it? I may do this and plug the hole as it has a slight leak from the tank. You said your stator and mag were fine, would I get similar symptoms if one of those went bad? this is an SBT motor and the old motor is still torn apart, I am not sure if those were switched or came with the new motor.

    Thanks,
    Carl

  6. #6
    Click avatar for tech links/info, donation request K447's Avatar
    Join Date
    Jul 2007
    Location
    near Toronto, Canada
    Posts
    36,579
    +1
    1,272
    SBT rebuilt engines do not come with any electrical parts. The old magneto stator would have been removed before the core was sent to SBT.

  7. #7
    ripcuda's Avatar
    Join Date
    May 2010
    Location
    Newman Lake, WA
    Posts
    2,389
    +1
    166
    As K mentioned... the mag/stator would have been swapped over to your new SBT engine. In K's signature links are pages of info. There's a page there detailing electrical ohm testing for the stator. I tested mine and it was within specs. The CDI was the culprit for my missing/bad spark.

    The tan wire from the overheat sensor (switch) tees into the grey wire from the low oil level switch and goes to the CDI. Both of these switches when triggered will ground their inputs... which in turn grounds the grey wire to the CDI which then the CDI will rev-limit. I'm pretty certain that the grey wire to the buzzer is also tied into this grey wire going to the CDI... and that by grounding that grey wire... the buzzer will also sound.

    So if your buzzer is continuous and it's not the low oil level switch (cause you unplugged it)... then I'm betting the CDI is bad and continuously grounding that grey wire... even though it's not actually rev-limiting anymore. I'd try to find a loaner to confirm it's bad if you can.

    I replaced the huge square oil tank with a smaller one up under where the battery used to sit. Now my battery sits in the spot where the huge square oil tank used to be. Much easier to get to. I just cut the wires off that used to go to the low oil level sender... being sure to tape off that grey wire so it can't ground out.

    There are no other "warnings" for the engine... only the over-heat switch... and the low oil level switch... on the Rio.

    Cheers!

  8. #8

    Join Date
    Mar 2014
    Location
    Austin Texas
    Posts
    56
    alright, swapped out the cdi and now it doesn't die, but still misfires pretty bad down low, I am going to check out the timing tomorrow and see if that is the issue. Nobody seems to sell the darn dial indicator gauges locally, will try with a caliper and see if that will work, anybody have other ideas for timing adjustment and testing? I had reconnected the oil tank plugs, after disconnecting them again the alarm is gone, probably just a bad sensor as the tank is full

  9. #9
    ripcuda's Avatar
    Join Date
    May 2010
    Location
    Newman Lake, WA
    Posts
    2,389
    +1
    166
    Check the woodruff key on the crank snout. Those can sheer and put the flywheel out of alignment.

    Does your engine backfire thru the carbs? Might have a look at your reeds... ensure they are entact and seal.

    You might trim the spark plug wires back a 1/4" and then screw the caps back on. Be sure you have the wires going to the right plugs.

    New CDI? What version? There is a high-start timing one and a regular timing one. (My Rio engine is an early model Virage 1200 with the regular timing flywheel). Each one needs the correct associated flywheel to go along with it. If you have a mismatch pair (CDI/flywheel), you can adjust the flywheel on it's adjustment timing hub to compensate.

    Cheers!

  10. #10

    Join Date
    Mar 2014
    Location
    Austin Texas
    Posts
    56
    I have not checked the key, I attempted to check the timing with a timing light but it doesn't seem there is enough ignition power to make it light or something else is wrong with the wires, I tested the light on my truck to be sure and it worked fine there. One spark plug (mag) when I pulled it out had the gap closed so that would be at least a portion of my lack of spark on that cylinder. The middle cylinder seems to be running right (medium brown color), and the PTO is just rich but still sparking. I may try trimming the wires and put them back together, but if no power is going through the wire either the wire has a short or something in it or the ignition module may also have an issue... I cant check the timing any other way.

    Haven't heard any backfiring, just nothing at all until middle range rpms (4k-ish) from one cylinder at least.

    I matched up the CDI with the one that was in the boat already, it is a 379 not really sure if that means it is a high timing or regular.

    Oh, and you have the boat listed as a 4 seater, it can hold 5 according to the capacity tag on mine, one has to be on the front layout deck pad.

Page 1 of 4 1 2 3 ... LastLast

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. Sun n' Sea Rio Step Jet (Polaris Powered Sugar Sand Jet Boat) - Informational Thread
    By ghostinstallations in forum Polaris Tech Tips and Info
    Replies: 19
    Last Post: 06-30-2015, 06:00 AM
  2. sun n sea rio not pumping fuel
    By rm12577 in forum Polaris PWC Performance
    Replies: 5
    Last Post: 07-13-2014, 01:45 PM
  3. Replies: 9
    Last Post: 04-19-2013, 10:01 PM
  4. Lost A sea doo key when i fell of the stand up
    By MyGreenGumby in forum Sea Doo Open Discussion
    Replies: 7
    Last Post: 09-09-2007, 11:09 PM
  5. wont start when warm (hot) fix...
    By brotherdon in forum Polaris Open Discussion
    Replies: 1
    Last Post: 07-03-2007, 11:03 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
  •