05 RXT Loss of Power

[NetBret]

Hey everyone, new to the forum and wanted to run a situation I ran into last season. On average I run around 7900rpm at 69mph but recently on my last two outings, my MPH has dropped to 60mph and rpm's were the same as above. My SC washers were done at around 25hrs and I'm at 88hrs now. I've checked the SC and it doesn't spin freely.

So far I've just had the wear ring and the impeller shaft boot replaced with no change. Also the shop that did the repairs recently said the the prop looked fine.

Any Ideas?

 

[Dr Honda]

If you have the same RPM's... then your supercharger probably isn't slipping.

Try this.... pull your carbon ring aback a little, and put a blob of waterproof grease on the face of it. Your carbon ring could be leaking just enough to let some air in... and that will slow you down. If that is the problem... the grease will seal it up, and you speed will come back. If the grease fixes it... you will want to replace the carbon ring, and it's supporting parts.

 

[NetBret]

If you have the same RPM's... then your supercharger probably isn't slipping.

Try this.... pull your carbon ring aback a little, and put a blob of waterproof grease on the face of it. Your carbon ring could be leaking just enough to let some air in... and that will slow you down. If that is the problem... the grease will seal it up, and you speed will come back. If the grease fixes it... you will want to replace the carbon ring, and it's supporting parts.

Tony, thanks for the tip, I'm still learning the in's and out's of my ride but I do have a shop manual to guide me and I'm not afraid to get into the machine . Sorry for being ignorant but when your referring to the carbon ring, is that located on the inner side of the SC and do I have to remove the SC to get to it?

 

[Dr Honda]

The carbon ring is your driveshaft seal. When it starts to leak... air will get into the pump... and when you are compressing/pumping air... you aren't pumping water.

In an extreme case... the ski won't even move.

 

[NetBret]

The carbon ring is your driveshaft seal. When it starts to leak... air will get into the pump... and when you are compressing/pumping air... you aren't pumping water.

In an extreme case... the ski won't even move.

I'll check into that area...

 

[Michael211_2000]

If you can pull your carbon ring back easily, that'd be your problem. It should be rather difficult to pull the bellows back (the carbon ring is in the end of the bellows, the bellows is acting like a spring pushing the carbon seal against a stainless steel ring that's on your driveshaft). It should be challening to push/pull back by hand... SeaDoo actually makes a lever like tool to push the carbon ring back to remove the clip that holds that stainless steel ring onto the driveshaft.

- Michael

 

[bretster]

Are you checking your speed via the dreamo meter? Can you noticeably feel a drop in mph or are you relying on the factory speedo? These frequently read inaccurate MPH and are not reliable. Have you checked your OPAS? These frequently drop and scrub speed. If your RPMS are consistent and haven't changed Dr Honda is correct in his statement that the S/C'er is not slipping.

 

[NetBret]

If you can pull your carbon ring back easily, that'd be your problem. It should be rather difficult to pull the bellows back (the carbon ring is in the end of the bellows, the bellows is acting like a spring pushing the carbon seal against a stainless steel ring that's on your driveshaft). It should be challening to push/pull back by hand... SeaDoo actually makes a lever like tool to push the carbon ring back to remove the clip that holds that stainless steel ring onto the driveshaft.

- Michael

Thanks for the details...I'm hoping to look into that area sometime this week.

 

[NetBret]

Are you checking your speed via the dreamo meter? Can you noticeably feel a drop in mph or are you relying on the factory speedo? These frequently read inaccurate MPH and are not reliable. Have you checked your OPAS? These frequently drop and scrub speed. If your RPMS are consistent and haven't changed Dr Honda is correct in his statement that the S/C'er is not slipping.

I'm relying on the factory speedo. However I know someone that's going to let me borrow a GPS so I can compare my speedo with the GPS and see if I'm having any issues with it.

It's interesting you mentioned something about the OPAS. I've read a couple posts and figured I'd look at that area next once I take a test drive with the GPS and look at the carbon ring. I didn't know that those could actually drop down.

 

[NetBret]

Alright, I have some updates and questions. I used a GPS and found that my factory speedo was only off by 1-2mph so that area is ruled out. I looked at the OPAS while out of the water and didn't see anything dropping or unusual. I put it in the water and rode as a passenger and looked at that area while riding and didn't see any excessive wake that I could tell.

I then went into the Bellows area to check the carbon ring and couldn't move the bellow in the area that's toward the rear of the ski, but toward the engine side, that area was difficult to move by hand but I was able to move it slightly with much pressure. I think that if I was going to try to put some type of waterproof grease on the carbon ring, I'd probably need some type of tool like micheal211_2000 suggested.

Should the bellow seal be tight on both sides?

 

[bretster]

It sounds tight to me. Try the grease. You could be bleeding air? Do you feel any cavitation? The motor is doing its job of revving to the proper rpms. The prob is either on the propulsion side or something dragging IMHO. Check your grate, plate, reverse bucket for loose bolts. Ive seen a loose grate do this.

 

[NetBret]

It sounds tight to me. Try the grease. You could be bleeding air? Do you feel any cavitation? The motor is doing its job of revving to the proper rpms. The prob is either on the propulsion side or something dragging IMHO. Check your grate, plate, reverse bucket for loose bolts. Ive seen a loose grate do this.

I'll give the grease a try and would I be correct on applying it to the bellow side toward the engine? and if so since it's difficult to pull the bellows back should I get a tool to do this?

Also I would say I feel some cavitation out of the hole...it doesn't respond like it use to. The dealer just replaced the wear ring in the pump and I'm surprised that when I mentioned the sames things to them that I've mentioned in this post that they didn't think to check the carbon ring and that area as well. The dealer did offer to look at it again but I'm hesitant on bringing it back thinking they'll soak me for some more things that won't fix my issue.

I also checked the grate and reverse bucket and everything feels tight.

 

[Michael211_2000]

If the OPAS paddles aren't rising up automatically as they should, they could cause some drag. They are held in the down position by springs, and water pressure from the pump pushes them up at higher speeds so they won't cause drag.

I think you aught to take it back to the dealer and describe the symptoms to them and see what they say... they may need to check the OPAS system for correct operation. You may have to pay them some for a diagnostic, but you could spend alot of time trying to figure this out on your own by trial and error. You shouldn't need to put grease of any kind on the carbon ring, the whole idea of it being a "carbon" ring is that the carbon provides both the seal and the lubrication for the seal.

You shouldn't be feeling any cavitation upon accellerating unless 1) the carbon ring is letting air get into the water flow (either not tight enough or possibly the carbon ring is just worn out) or 2) you have excessive space between the wear ring and the impeller (but you had the wear ring changed out with no improvement, so seems unlikely) or 3) you have really bad dinged up impellor blade(s) (which the dealer said looked just fine when they changed out the wear ring).

I kinda think this leads us to suspect either the carbon ring has worn out (and is therefore letting air get sucked into the jet pump when you accellerate or try to go fast... but I believe these things also leak water into the hull pretty badly when they're worn out???) or your OPAS paddles are stuck in the down position all the time causing excessive drag. The dealer would need to pressurize the OPAS system pressure lines to check them for correct operation, I believe.

I'd let the dealer look at it again... but be sure to ask what the diagnostic charge will be for looking at it 1st!

- Michael

 

[Michael211_2000]

[Should the bellow seal be tight on both sides?

There is a clamp on the back end (towards the stern) of the bellows that secures it to the hull. Ergo, yes it should be tight on both sides as a result. I just checked a diagram and there are 2 clamps on the bellows: one holds it to the hull and the other clamp holds the carbon seal in the end of the bellows. The bellows itself pushes the carbon ring against the stainless steel support ring on the driveshaft.

http://partsfinder.onlinemicrofiche.com/seadooforums/Seadoo_oem/Seadoo_PWC.asp?Type=13&A=140&B=13

- Michael

 

[bretster]

If the OPAS paddles aren't rising up automatically as they should, they could cause some drag. They are held in the down position by springs, and water pressure from the pump pushes them up at higher speeds so they won't cause drag.

I think you aught to take it back to the dealer and describe the symptoms to them and see what they say... they may need to check the OPAS system for correct operation. You may have to pay them some for a diagnostic, but you could spend alot of time trying to figure this out on your own by trial and error. You shouldn't need to put grease of any kind on the carbon ring, the whole idea of it being a "carbon" ring is that the carbon provides both the seal and the lubrication for the seal.

You shouldn't be feeling any cavitation upon accellerating unless 1) the carbon ring is letting air get into the water flow (either not tight enough or possibly the carbon ring is just worn out) or 2) you have excessive space between the wear ring and the impeller (but you had the wear ring changed out with no improvement, so seems unlikely) or 3) you have really bad dinged up impellor blade(s) (which the dealer said looked just fine when they changed out the wear ring).

I kinda think this leads us to suspect either the carbon ring has worn out (and is therefore letting air get sucked into the jet pump when you accellerate or try to go fast... but I believe these things also leak water into the hull pretty badly when they're worn out???) or your OPAS paddles are stuck in the down position all the time causing excessive drag. The dealer would need to pressurize the OPAS system pressure lines to check them for correct operation, I believe.

I'd let the dealer look at it again... but be sure to ask what the diagnostic charge will be for looking at it 1st!

- Michael

+1 Best advice!!

 

[NetBret]

If the OPAS paddles aren't rising up automatically as they should, they could cause some drag. They are held in the down position by springs, and water pressure from the pump pushes them up at higher speeds so they won't cause drag.

I think you aught to take it back to the dealer and describe the symptoms to them and see what they say... they may need to check the OPAS system for correct operation. You may have to pay them some for a diagnostic, but you could spend alot of time trying to figure this out on your own by trial and error. You shouldn't need to put grease of any kind on the carbon ring, the whole idea of it being a "carbon" ring is that the carbon provides both the seal and the lubrication for the seal.

You shouldn't be feeling any cavitation upon accellerating unless 1) the carbon ring is letting air get into the water flow (either not tight enough or possibly the carbon ring is just worn out) or 2) you have excessive space between the wear ring and the impeller (but you had the wear ring changed out with no improvement, so seems unlikely) or 3) you have really bad dinged up impellor blade(s) (which the dealer said looked just fine when they changed out the wear ring).

I kinda think this leads us to suspect either the carbon ring has worn out (and is therefore letting air get sucked into the jet pump when you accellerate or try to go fast... but I believe these things also leak water into the hull pretty badly when they're worn out???) or your OPAS paddles are stuck in the down position all the time causing excessive drag. The dealer would need to pressurize the OPAS system pressure lines to check them for correct operation, I believe.

I'd let the dealer look at it again... but be sure to ask what the diagnostic charge will be for looking at it 1st!

- Michael

The more I think about it your probably right to get the proper diagnostics first just to save time and wasting even more money during the process. I feel confident that we're getting close to a couple of areas and should be running great soon. So I'll go ahead and get it back to the dealer this week.

Thanks to you and everyone that has posted on this so far, everyone's help has been invaluable! I'll let you know know what they find.

 

[Michael211_2000]

Great! And yes we'd would love to hear what they find out about it so please come back and follow up with whatever they find out!

- Michael

 

[NetBret]

Hey everyone...after a couple of months of being in and out of the dealer with my ski, I wanted to give a report on my findings.

Right now I've had the following parts replaced to fix my performance issue (top speed dropped to 60mph 7200rpm).
Wear Ring
Neoprene Seal
Reducer (piece that goes between the pump and the hull)
Rebuilt Supercharger (full rebuild)
Fuel Filter

The dealer also tested the fuel pressure and found that it dropped slightly (why fuel filter was replaced) when they tested it in the lake, and tested the OPAS system and found it to be functioning properly.

Now at this point, I'm running a top speed of 63.4mph (used Garmin GPS) and my performance from a dead stop has been returned to what I'm use to experiencing. It definitely launches when you go WOT. The dealer said that they have tried everything possible and found that all the parts related to this problem have been replaced. I figured that right now I just wanted to run it for this season before it's over and possibly try again with some other things later toward the end of the season.

I'd be willing to look at some more options but I would like to give my wallet a break...

 

[Michael211_2000]

Nice avatar! Nice looking machine, I'd like to have a green RXT someday to go with my red one!

Why'd the wear ring need replacing? Did they have anything to say about the condition of the impeller? What's top rpm now?

- Michael

 

[Scottohno]

im also experiencing this problem. it seems as if my RXP takes longer to accelerate, and if i REALLY try on very smooth water i can hit 67mph on the factory speedo. i have some pretty bad cavitation, more noticable with 2 people riding. i was really leaning toward a wear ring but if i have it replaced i may also have the carbon seal replaced too. i have no shop manual, i have the dealer do everything. i can hit 7600RPM no problem, but getting there is a pretty grueling process.

one thing i think MAY HAVE made a VERY SLIGHT difference is i checked the antifreeze level and topped it off. it seems to have a bit more power now, but with the heat index at 105* the loss of power could be the extreme temperature, the 242 hours on it, the wear ring neding replacing, or that carbon seal (which i believe to be original)

i would like to thank you guys for your input in this thread, and say that though im new to the community i do feel welcome here. THANKS!

 

[Michael211_2000]

The wear ring is easy to replace, all you need is a freezer and pair of pliers.... pull the pump (again, easy it takes about 10 minutes or so), put the pump in a freezer overnight along with the new wear ring, remove pump from freezer and use pliers to pull on edges of wear ring and it'll slip right out. Remove new wear ring from freezer, push it right into the pump. Now re-install the pump (takes maybe 20 minutes).

The carbon ring is a little harder to replace, but only because you have to pull the driveshaft out the back of the hull (undo 1 clamp at PTO, push the retaining clip off the driveshaft at the stainless steel disk, then slide the driveshaft out the back of the hull). Still, it's only a 30 minute job if you already have the pump out. If it's not leaking (at idle or at anchor) and not sucking air under hard accelleration, I'd leave it alone.

- Michael

 

[NetBret]

Nice avatar! Nice looking machine, I'd like to have a green RXT someday to go with my red one!

Why'd the wear ring need replacing? Did they have anything to say about the condition of the impeller? What's top rpm now?

- Michael

It's kinda funny buy I was looking to buy an 06 RXT that was red. Unfortunately when I went back to make an offer (a couple of hours later) he already sold it. I'm still happy with the 05 and I like the green color.

Also, the reason the wear ring was replaced was that it had some scoring on it from ingesting some seashells last season...this was the first thing they replaced but didn't change anything. The dealer looked at the impeller and said it looked fine. I'm not sure about the top rpm since I was focusing on the speed, but I'm going to ride it this weekend and I'll get back with you on the rpm's.

 

[NetBret]

im also experiencing this problem. it seems as if my RXP takes longer to accelerate, and if i REALLY try on very smooth water i can hit 67mph on the factory speedo. i have some pretty bad cavitation, more noticable with 2 people riding. i was really leaning toward a wear ring but if i have it replaced i may also have the carbon seal replaced too. i have no shop manual, i have the dealer do everything. i can hit 7600RPM no problem, but getting there is a pretty grueling process.

one thing i think MAY HAVE made a VERY SLIGHT difference is i checked the antifreeze level and topped it off. it seems to have a bit more power now, but with the heat index at 105* the loss of power could be the extreme temperature, the 242 hours on it, the wear ring neding replacing, or that carbon seal (which i believe to be original)

i would like to thank you guys for your input in this thread, and say that though im new to the community i do feel welcome here. THANKS!

You acceleration was exactly what mine was doing to a degree. When I started troubleshooting the problem, I actually was leaning toward the supercharger, but from the outward appearance it looked fine (no slip when trying to spin the s/c). when I had the s/c removed the dealer initially thought that the washers were worn so we started off with that (was rebuilt once due to a washer failure around 30hrs). Once I had it back in the water nothing changed. The dealer then rebuilt the entire unit...no additional labor since they misdiagnosed the problem and also didn't charge me for the 1st rebuild kit. After this was done my acceleration was back and launches you from the line again. Have you had your washers replaced yet? How many hours to you have on it?

 

[Scottohno]

\Have you had your washers replaced yet? How many hours to you have on it?

243 hours, had the SC replaced twice, engine replaced once, and the washers replaced. it seems to be cavitating pretty bad now. the revs are fine, but i seem to have no traction.

 

[Michael211_2000]

Check the seal, try to pull the bellows back... it should be very hard to pull it back from the stainless steel disk that's on the driveshaft. It may simply need to be tightened up. If it's too loose hard suction (from accelleration) will open it up and suck air into the pump.

If not that, I'd go ahead and pull the pump out and check the wear-ring and impeller for foreign objects (say, a rope either around the driveshaft or wound up thru the impeller) or excessive wear (grooves in wear ring, dings in impeller blades leading edges). This is all easy stuff to check, just pull it under a shade tree and get to it!

- Michael