2004 RXP Vibrations 2k RPMS and higher

[mr_meow]

A brief history of the ski:
My brother bought this ski roughly 4-5 years ago and other than oil changes no other maintenance has been done. It currently has just a hair over 200 hours on it. I'm going to take a stab in the dark and say that when it was bought it had maybe ~120 hours on it. I don't know much of the history of it and I have no idea if the SC has ever been rebuilt (though I highly doubt it).

Current Issue:
Took the ski out for the 2nd run of the year. It was running fine with no issues for the 1st hour. Around hour 2 we were cruising around 40mph and all of the sudden we lost a great deal of forward power. It's like someone just flipped a switch. There was also an audible vibration that increased in frequency and volume as the rpms increased. At idle, it sounded normal but as you gave it gas and the vibrations returned without an increase in forward thrust. We let it cool for an hour or so and started it back up. It ran fine for ~5min and the exact same symptoms returned.

I must apologize for my lack of knowledge about jet skis. While I am very mechanically inclined I just don't have a whole lot of experience in dealing with the mechanics of jet skis. I've tried searching this forum for my symptoms to try to determine the issue, but I've had no luck. Most searches turn up bad SC's (which seems very likely but nobody mentions vibrations with a bad SC, only no power). I've also come across no good wear ring conditions. This matches the vibration issue but I would think that this would be a slow progression that gradually gets worse, not a "light switch" problem.

We do a lot of river riding that is prone to sticks, trash, and just normal dirt (Ohio River). It's very possible that we sucked something in but at the time this problem reared it's head we were in clear water. Also, my dad added an unknown amount of "regular" oil (<1 L) prior to our trip unbeknownst to me.

My question is, what should I look at first? I'd like to at least check the simple things myself without having to take it to a service center and just say, "fix it".

Thanks for any advice, comments, or suggestions in advance!

 

[red2blue]

A brief history of the ski:
My brother bought this ski roughly 4-5 years ago and other than oil changes no other maintenance has been done. It currently has just a hair over 200 hours on it. I'm going to take a stab in the dark and say that when it was bought it had maybe ~120 hours on it. I don't know much of the history of it and I have no idea if the SC has ever been rebuilt (though I highly doubt it).

Current Issue:
Took the ski out for the 2nd run of the year. It was running fine with no issues for the 1st hour. Around hour 2 we were cruising around 40mph and all of the sudden we lost a great deal of forward power. It's like someone just flipped a switch. There was also an audible vibration that increased in frequency and volume as the rpms increased. At idle, it sounded normal but as you gave it gas and the vibrations returned without an increase in forward thrust. We let it cool for an hour or so and started it back up. It ran fine for ~5min and the exact same symptoms returned.

I must apologize for my lack of knowledge about jet skis. While I am very mechanically inclined I just don't have a whole lot of experience in dealing with the mechanics of jet skis. I've tried searching this forum for my symptoms to try to determine the issue, but I've had no luck. Most searches turn up bad SC's (which seems very likely but nobody mentions vibrations with a bad SC, only no power). I've also come across no good wear ring conditions. This matches the vibration issue but I would think that this would be a slow progression that gradually gets worse, not a "light switch" problem.

We do a lot of river riding that is prone to sticks, trash, and just normal dirt (Ohio River). It's very possible that we sucked something in but at the time this problem reared it's head we were in clear water. Also, my dad added an unknown amount of "regular" oil (<1 L) prior to our trip unbeknownst to me.

My question is, what should I look at first? I'd like to at least check the simple things myself without having to take it to a service center and just say, "fix it".

Thanks for any advice, comments, or suggestions in advance!

infckncredible.

seriously.

Okay...all that aside... crawl under the ski and look into the pump tunnel and around the prop shaft. Remove anything that don't belong. Check the back of the pump...see if you can see anything caught in the pump.

With the motor warmed up...and off. Check the oil...it should read between the bends.

And do your brother a favor and have that sc rebuilt. And what the hell..have the oil and filters changed as well. "Regular" oil?...uhm...not 4stroke motor cycle oil?

 

[mr_meow]

I understand about the oil. To be fair he couldn't remember which oil he put in (conventional or motorcycle) or how much. Knowing what he has at the house I can only assume it was conventional. I do know that it was definitely not the mineral oil it requires. My dad had a stroke last July and hasn't been the same... He knows better (when thinking clearly) and felt terrible afterwards. I'll start with the inspection of pump tunnel and shaft.

 

[mr_meow]

Checked the inlet/outlet of the pump. Nothing was in it and could see any excessive wear or hit marks. Should I look at removing the pump outlet and replacing the wear ring?

 

[mr_meow]

Checked the inlet/outlet of the pump. Nothing was in it and I couldn't see any excessive wear or hit marks. Should I look at removing the pump outlet and replacing the wear ring?

 

[red2blue]

Hmm...woulda bet on something around the prop shaft...oh well. Pulling the pump ain't hard...should be able to remove, inspect and reinstall in less than an hr and a half...first time out.

A prop removal tool would be a nice thing to have though after you have the pump off the ski.

When you said in the orriginal post..."It ran fine for ~5min and the exact same symptoms returned."...does that mean you were able to get the r's back up over 7K rpm...hopefully? Have you checked the sc washers yet?

 

[mr_meow]

I won't be able to take another look at it for a week or two. I'm outta town until then. I'll take a second look at the pump again when I have more time and make sure nothing is wrapped around the shaft or stuck in the prop. I'll also pull the intake off the SC and try to spin it.

I was able to get it back over 7k the second time after it had sat for an hour or so. It ran and pulled like nothing had ever happened. But then the same noise and vibrations came back.

In the meantime I'll order an prop removal tool. It appears that come in two sizes: 22 and 28mm. You wouldn't happen to know which one I need, would you? If I remove the prop are there any seals, gaskets, or bearings that will need to be replaced just by opening it up and removing it? I want to make sure if I take this thing off I have everything I need to put it back together.

Thanks again for the help. It is really appreciated!

 

[trapperjack1]

you will also need a 12mm alan wrench
witch holds the bottom while you turn the top

 

[Michael211_2000]

It sounds like the machine needs to be gone over thoroughly... and that SC definitely needs to be rebuilt! What about new spark plugs? Take a fresh new set with you and change the existing ones out failing plugs can cause the engine to miss and run terrible too, ask me how I know this! Change engine oil and filter (take proper engine oil and filter with you!). Read instructions/forum posts regarding techniques for changing engine oil properly!

Quick/easy check for SC operation, grip the SC to carb air hose with 1 hand tightly, start the engine with other hand (presuming on a trailer) and give it some throttle (just a little goosing it)... you should feel the air hose expand under your grip as the SC makes boost. If you feel nothing, then the SC is shot (which I'd rather expect at this point honestly!). You might have to warm it up 1st on the water, the SC might spin enough when cold to work but then start slipping uncontrollably as it heats up (wrong engine oil can cause excessive SC slip and loss of boost pressure also). Do the engine oil and spark plugs 1st though, sounds like they really need it.

If not running with water hose on flush port on trailer then only run it a few seconds (like < 20 seconds!) for the SC test. If you hook up flush port to waterhose this is the correct order: Engine on, water on... water off, engine off! It's important! Still limit run time on trailer even with waterhose to under 5 minutes (the jetpump seal gets hot, and the ride plate cannot transfer heat without being in the water so it's heating up the entire time the engine is running).

I'd check/correct these things before pulling the pump. If the SC has failed (easy to check) then pulling the pump out isn't going to get you anywhere. SC's are supposed to be completely rebuilt every 100 hrs of operation... and '04 4TEC superchargers had the ceramic clutch washers which were prone to cracking breaking and falling apart inside of the engine (bad mojo!!!) even when they had less than 100 hrs on them.

Finally if nothing else helps then pull the pump out and visually inspect it for damage to the impeller or anything stuck/wrapped up inside there. That it seems to run ok for a few minutes before starting to shake/vibrate really makes me think the jet pump is ok though, if there was a problem back there you'd feel it as soon as you start up the engine and start driving it there shouldn't be a delay of symptoms IMHO. Actually the jetpump probably should be pulled and carefully inspected anyways, just because it's difficult to inspect thru the water inlet... but check the engine for issues 1st.

- Michael

 

[Michael211_2000]

I want to make sure if I take this thing off I have everything I need to put it back together.

If you take the pump off to inspect it, you shouldn't need to remove the impeller for inspection unless you actually see/feel something wrong (ie. bent blade(s) or bad bearings). If the impeller turns freely and smoothly and isn't damaged once you have the pump out and on your tailgate, I wouldn't remove the impeller. If you actually have to remove the impeller you're almost certainly going to have to replace parts as a result so you won't be getting it back together that weekend. The impeller can be changed without changing seals/bearings, the wear ring can be removed and replaced without removing the impeller. Check the engine issues 1st IMHO.

- Michael

 

[red2blue]

Re the prop removal tool. Get the taller of the two. It'll allow you to keep the nose on the prop.

 

[mr_meow]

I got the chance to swing by and take a second look at the pump. This time glaring out at me from the outlet side of the pump was a stick roughly 3/4" in diameter and a couple inches long lodged in it. It took about 15 minutes and I was able to fish it out in several pieces. I didn't get a chance to put it in the water to try it out but I'm assuming that's what caused it. I'm going to head back this weekend and hopefully put it in the water just long enough to check it out. Next step if that goes well is pulling the SC and rebuilding it. I feel mildly embarrassed I didn't see that stick before. Thanks for everyone's input!

Another question: How many hours does an "average" jet ski see in an season?

 

[Michael211_2000]

I doubt there is a correct answer to that question... everybody is different, weather conditions in your area and work/family requirements are all going to affect the amount if hours you use your watercraft yearly. If I had my choice I'd be on the lake every single day for several hours each day... but, that just ain't happin. :-(

ps. You still have some important maintenance issues to address in the engine before you use this machine further! Don't skip the maintenance just because you found the stick in your pump finally.

- Michael

 

[mr_meow]

I doubt there is a correct answer to that question... everybody is different, weather conditions in your area and work/family requirements are all going to affect the amount if hours you use your watercraft yearly. If I had my choice I'd be on the lake every single day for several hours each day... but, that just ain't happin. :-(

I understand completely! I don't work because I enjoy it, I work so I can do the things I enjoy! I wasn't sure if there was an average number...

ps. You still have some important maintenance issues to address in the engine before you use this machine further! Don't skip the maintenance just because you found the stick in your pump finally.

I agree with you. I had no idea about the SC needing rebuilt every 100 hours or the issue with the ceramic washers. The plan is to stick it in the water, make sure that fixes the vibes then pull the SC and send to Jerry for a rebuild. This forum has a wealth of info and if it wasn't for searching and reading on here I'd have no idea about the issues with it. We've been very, very lucky so far!

 

[Michael211_2000]

I'd wager getting the stick out of the jetpump will make a HUGE difference. Anything that messes up the water flow thru the pump wil cause problems. Now why "It ran fine for ~5min and the exact same symptoms returned" I have no idea the stick should have caused symptoms from the moment you started it up IMHO. That's just weird!

- Michael

 

[mr_meow]

I ended up pulling the intake off of the supercharger and found it was filled with oil. So, instead of taking it out to test the pump and chancing something going wrong with the SC I went ahead an pulled it off. It was pretty simple. I was expecting a lot worse. I'm not sure what the visual difference is between the ceramic washers and the new steel ones. I've posted some pics below and hopefully someone can tell me some info on them (material, condition, are any missing, etc?) there is a "wear" mark on the shaft of the SC that doesn't appear to be normal wear. Has anyone seen this before? Is it something to be concerned about?

My next step is to ship this off and get it rebuilt. I'm loving this forum!

Many thanks for all the help!

 

[Michael211_2000]

There's not really any visual difference, the only way I know of is to hold them in your hand the ceramic's weigh almost nothing like they're made of plastic almost while the steel ones feel like you're holding steel washers in your hand. Also a magnet won't attract the ceramics... but you still have to have them off the shaft to check that. The rebuild will include new upgraded steel washers so it really doesn't matter at this point what they are they are going in the rebuilder's trash!

I can't figure what made that wear mark. Weird!

With some 200 hrs of operating time on it, I think you're lucky all it blew was the oil seal. That's remarkable IMHO!

- Michael

 

[mr_meow]

So I got the SC back and am in preparations to reinstall it once I get back down there. I noticed Seadoo used some type of thick grease to install the SC shaft into the block. Is this a special type of lube that must be used? I had planned on using white lithium grease to reinstall but I'm concerned that it may affect the clutch performance.

Thanks again! So close to having this thing back in the water!

 

[Michael211_2000]

That's ani-seize compound. Pick some up at your local auto parts and swipe a dab cround the SC housing where it goes into the engine. It keeps the supercharger from becoming stuck in the engine block. Use anti-seize for this don't use regular grease (which will dry out and harden over time!).

Let us know how it runs once you got it back together.

- Michael