Page 1 of 2 1 2 LastLast
Results 1 to 10 of 16
  1. #1

    new 2012 300x rpm problem only 14 hours

    Hello everybody i am newly registered to the forum but i have done hours of searching to try and diagnose my problem. I bought a leftover 2012 300x new, followed proper break in period (10 hours of varied rpm, no WOT from stop, minimal/no WOT at speed) and as i ride salt water, fully clean, wash, and flush the ski, engine bay, and motor; all with no problems.

    It wasn't until around 11 hours i had the first maintenance preformed by the dealer and days later took the ski out to see what it can do. All was good until at around 13/14 hours i noticed rpm and starting problems.

    At idle, i would open throttle (about half maybe 3/4 throttle) and rpm jumps to around 5000, then almost instantly stalls/drops by about 500rpm for half a second until it picks back up to normal (back to 5000 and i roll on the throttle increasing rpm as i take off). I have been riding it for about 2 or 3 hours this way and every time out of the whole it has that slight blip in throttle and sudden loss of power then takes off no problem and maintains good speed/rpm @ wide open throttle (ski indicates max 7410 @ 67mph in moderate/heavy chop).

    I also noticed that in the water- upon starting, ski will crank just fine but engine will not start up nice and clean as it did prior to maintenance. It almost has a slight bog until it actually begins to run. The starting does not seem to be a severe problem it was just something i noticed and thought it could perhaps be related.

    Lastly WOT out of the hole, the ski seems to lag before it really pulls. (Possibly related to the slight stall in rpm but even when motor gets passed the rpm "blip" it seems rpm and boost are just fine) After research i understand this could be considered "cavitation." The ski is bone stock, and at one point during break in i sucked up some grit/sand but killed the motor as soon as i hit the shallow water and pushed it back into the deep, AND the dealer checked the impeller and said it looks good.

    Research has told me that my WOT rpm and speed are within range (speed is good max rpm possibly slightly low by a few hundred). I was wondering if possibly a loose SC belt could be the issue as once the ski was broke in i rode it very hard that day and research told me that even after 10 hours belt can stretch. Also common cause apparently seems to be exhaust filter fails causing plugs to foul, and or just a failing plug. Considering only 14 hours on the ski i am not convinced the exhaust filter failed but could believe that a plug could fail (which might explain the crummy start up in water). But in my un-professional opinion if it was a bad/fouled plug i would likely have effects in all rpm range not just out of the hole? Also the blip in the throttle is only felt under-load (in water) as when i had it on the trailer and was running it with the hose, i tried a quick pull of the throttle (1/2 throttle) and it revs just fine. Any input is much appreciated. I am mechanically inclined (turn a wrench for a living) but not in automotive so i am limited.

    Thanks!


  2. #2
    Take the time to smile sirbreaksalot's Avatar
    Join Date
    Jun 2007
    Location
    Brisvegas
    Posts
    4,157
    +1
    598
    First thing to check os exh filter

  3. #3
    nicjak's Avatar
    Join Date
    Mar 2008
    Location
    Warragul, Downunder
    Posts
    7,794
    +1
    625
    Sounds like a few problems. 1 exhaust filter 2 worn prop maybe.

  4. #4
    thanks, The more and more i search the more points to the exhaust filter. Considering I've herd people advise to change exhaust filter as early as 25-30 hours, I'm thinking ill grab one from the dealer so while its apart if i need to change it its good to go. I will take it apart tomorrow as the weather today is not cooperating and hopefully the marine kaki dealer has a filter in stock.

    I also discovered that i am not fully blowing out the water box as well as i should. I would typically kill the water from the hose and give it 3 or 4 quick revs till water stops coming out and kill the motor (within the 15 secs). But i just started it today on the trailer to check something and enough water came out that leads me to believe it could be the cause to a possibly early failing/ corroding internals.

    Also didn't realize but i have 19 hours on the ski problem started around 12. Thanks will update when filter is checked.

  5. #5
    nicjak's Avatar
    Join Date
    Mar 2008
    Location
    Warragul, Downunder
    Posts
    7,794
    +1
    625
    yep if you arent emptying the box that could be your problem, raise the front of your trailer give it a few quick blasts after turning water off. go back to the ski over the next few hrs or next day and start it do the same once it has warmed a little.

  6. #6
    Quick UPDATE: Click image for larger version. 

Name:	photo-2.jpg 
Views:	41 
Size:	102.2 KB 
ID:	332255 The weather is not cooperating so i won't be working on it today as planned but I purchased the new filter and plugs in advanced in case it needed changing. Upon inspection of filter i noticed it is the newer style with the hole in the center. (2013 and up i believe) I am curious because i was under the impression the 2012 filter was the full honeycomb and needed to stay as a full honeycomb. I asked the dealer and they said that is the "updated" version and is compatible. Do you all agree?

    Also i like the idea of blowing the water out while the ski is lifted never thought to do that. After i wash i keep the ski lifted for a few hours to allow the motor/engine bay to dry then apply the anti-corrosive so ill be sure to run it and clear it again after it sat for a while. Thanks.

  7. #7
    nicjak's Avatar
    Join Date
    Mar 2008
    Location
    Warragul, Downunder
    Posts
    7,794
    +1
    625
    yes thats the new updated filter for all models. most of us prefer the older part no

  8. #8
    So i finally am able to work on it. Here is what i found: down pipe side-Click image for larger version. 

Name:	image-3.jpg 
Views:	44 
Size:	93.5 KB 
ID:	332908exhaust ,manifold side-Click image for larger version. 

Name:	image-4.jpg 
Views:	52 
Size:	80.0 KB 
ID:	332909 I think the exhaust filter appears to be ok. Slight pulling away on one edge near the housing but otherwise looks clean. I figured since its apart ill replaced it with the new one anyway. Also i wanted to check my plugs as that was just an idea that could have possibly contributed to the problem.Click image for larger version. 

Name:	image-6.jpg 
Views:	59 
Size:	61.9 KB 
ID:	332910 In my opinion plugs look ok too. Considering re-installing i don't believe they are fouled.

    Anyway your opinions please. Should the plugs be changed? Based on the condition of the exhaust filter do you think it was contributing to my problem? (Theirs around 23 hours on the ski) Hopefully ill be out tomorrow or wed.

  9. #9
    I had only 10 hours on one jetski and the plugs were bad, can't really tell by looking nowadays. It doesn't hurt to buy a new set to try them out

  10. #10
    nicjak's Avatar
    Join Date
    Mar 2008
    Location
    Warragul, Downunder
    Posts
    7,794
    +1
    625
    filter looks great if you havent cleaned it up i would re install it, do the plugs have rust pitting on them? photos arent real clear. looks like someone was very heavy handed with the antiseize they may have gotten some on the electrode also damaging a plug.

    my opinion replace the plugs looks from re reading your previous posts it sounds like a hesitant start from condensation on the plugs, also the manifold side of the filter shows a slight rust pitt indicating moisture.

  11. +1 by:


Page 1 of 2 1 2 LastLast

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. Ultra 300X rpm Problem...
    By RXP-X 2011 in forum Kawasaki PWC Performance (4-stroke)
    Replies: 4
    Last Post: 05-11-2015, 06:20 AM
  2. Replies: 74
    Last Post: 04-29-2014, 11:38 AM
  3. 2012 RXPX RPM problem
    By gp1800r in forum 4-Tec Performance
    Replies: 12
    Last Post: 06-16-2013, 10:26 AM
  4. FS New Ultra 300x OEM Impeller 1.2 Hours
    By mjkzeus in forum Kawasaki Classifieds
    Replies: 5
    Last Post: 07-09-2012, 08:15 AM
  5. GTR IBR problems only 8 hours on ski.
    By USC_GTR215 in forum 4-Tec Performance
    Replies: 7
    Last Post: 06-01-2012, 02:26 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
  •