03 rxdi low rpms and speed issue

[Seadoo rxdi]

I just bought an 03 rxdi with 72 hrs on it. Here's the info.. when I test rode it i was only getting 40mph max(used phone gps) on a not too choppy lake. I did not look at the rpms at that time( I forgot). So I pull the pump the wear ring was beyond gone. I replaced it, and dremeled the edges of the impeller because it had quite a few Knicks. Also, about 3 of the pump vanes have chunks missing about the size of a quarter on each of the 3. The rest are fine. Also the intake grate has 1 of the vanes broken off completely, I didnt think this has anything to do with it though. The shoe plate is Intact and the sealant appears fine as well. The carbon ring doesn't leak water so I assume it's fine? I went ahead and changed the spark plugs and did a compression test. I got 135psi on both cylinders. After replacing wear ring and grinding down impeller knicks I took her back out. I'm now getting max 43mph roughly on a somewhat choppy water and 6400rpms. The thing starts up and idles perfect every single time at 1450rpms. Revs up just as it should as well. It gets a pretty good hole shot but I am now wondering If the impeller and/or pump vanes are the cause of my lower speed. I also changed oil in pump. It was not milky and there were no metal shavings

Here are a few pics of the impeller after grinding rough edges.

What do ya'll think? Should I replace it or have it fixed? What about the broken pump vanes? Some say they will cause very minimal performance loss, others say it will be a night and day difference. From what I've gathered this thing should be hitting closer 60mph at 6800rpms, correct?

 

[jhjesse]

You are missing 400-500rpms. Is the prop OEM or Aftermarket?
When you shut off the ski can you hear the raves cycle two times?
Is there any maintenance lights popping up while riding?

 

[Seadoo rxdi]

You are missing 400-500rpms. Is the prop OEM or Aftermarket?
When you shut off the ski can you hear the raves cycle two times?
Is there any maintenance lights popping up while riding?

The prop is oem as far as I know. How could I tell though? The guy I bought it from has not done anything to it other than replace the battery so he claims. Yes I can hear the raves cycle twice when shutting off. No maintenance light. When I put the lanyard on it does beep and continue to beep until started. Is this normal?

 

[etemplet]

Having just going through impeller replacement and pump replacement I can say with conviction your prop and pump are not the issue. Perhaps some effect but not much. This venturi gets me the same speed as the one in good shape. I sure can't tell the difference. Look at the engine and good luck !!

 

[Seadoo rxdi]

The ski doesn't take on water and seems to run extremely well without hesitation or bogging down even when you go WOT from a dead stop. I went ahead and ordered a new pump housing because I am pretty convinced 3 fins with quarter sized chunks missing may be the culprit ($360) and an intake grate($20) I will take the impeller off once the impeller removal tool comes in and take it my local prop shop and have them fix it. Does anyone know any tricks to removing the impeller without the tool? I would like to get it off today and drop it off at my prop guy so I can test it out this weekend with the new jet pump and intake grate and fixed impeller.

 

[Seadoo rxdi]

Having just going through impeller replacement and pump replacement I can say with conviction your prop and pump are not the issue. Perhaps some effect but not much. This venturi gets me the same speed as the one in good shape. I sure can't tell the difference. Look at the engine and good luck !!View attachment 36074

My pump vanes are worse than yours..when I pull it off later today I will get some pics of it posted. There are so many mixed reviews on this..some say the pump vanes wont affect anything and others say it will tremendously. I believe seadoo themselves say it will on their website. What about adjusting the rave valves? Would turning the blue screws out a bit affect my top speed/rpm?

 

[etemplet]

You need the tool absolutely. Matt Braley has performance impellers at great prices. I'd contact him to see what he has for your ski. The impellers I got from him were $125ish.

 

[Seadoo rxdi]

You need the tool absolutely. Matt Braley has performance impellers at great prices. I'd contact him to see what he has for your ski. The impellers I got from him were $125ish.

Is he a guy on these forums? Or does he have a website I can order from? Thanks!

 

[etemplet]

My pump vanes are worse than yours..when I pull it off later today I will get some pics of it posted. There are so many mixed reviews on this..some say the pump vanes wont affect anything and others say it will tremendously. I believe seadoo themselves say it will on their website. What about adjusting the rave valves? Would turning the blue screws out a bit affect my top speed/rpm?

Ha ha... yes there will always be mixed opinions. Opinions are what people have that don't have experience. In this discussion I just went though this personally and swapped parts a few times. I would be surprised if any of the lower end components affect your performance substantially. With a good wear ring and a decent impeller it's gonna work. I played with the raves on my skis but they are carbureted. You can move the opening point a bit but it won't solve your problem. Perhaps you need to take them out and clean them up?

Just some thoughts on the problem. and stating what I have experienced in the last few weeks with my ski. Currently the ski is running its fastest with the damaged parts. LOL Go figure. Good Luck.

 

[Seadoo rxdi]

Ha ha... yes there will always be mixed opinions. Opinions are what people have that don't have experience. In this discussion I just went though this personally and swapped parts a few times. I would be surprised if any of the lower end components affect your performance substantially. With a good wear ring and a decent impeller it's gonna work. I played with the raves on my skis but they are carbureted. You can move the opening point a bit but it won't solve your problem. Perhaps you need to take them out and clean them up?

Just some thoughts on the problem. and stating what I have experienced in the last few weeks with my ski. Currently the ski is running its fastest with the damaged parts. LOL Go figure. Good Luck.

Ha ha... yes there will always be mixed opinions. Opinions are what people have that don't have experience. In this discussion I just went though this personally and swapped parts a few times. I would be surprised if any of the lower end components affect your performance substantially. With a good wear ring and a decent impeller it's gonna work. I played with the raves on my skis but they are carbureted. You can move the opening point a bit but it won't solve your problem. Perhaps you need to take them out and clean them up?

Just some thoughts on the problem. and stating what I have experienced in the last few weeks with my ski. Currently the ski is running its fastest with the damaged parts. LOL Go figure. Good Luck.

Well maybe I just wasted $360 then haha...time will tell I suppose. I thought about testing the fuel pump pressure but i doubt that would be the culprit because it will rev up quickly over 7000 to the limiter with reverse bucket down. Is it normal for it to go really slow in reverse even with high rpms like that? Figured they weren't meant to go very fast in reverse. This is my first ski but have lots of experience with inboard boats and cars.

 

[Seadoo rxdi]

Does anyone know if I can just take out the inline fuel filter and put a t fitting with my gauge to test the fuel pressure?

 

[mikidymac]

I wouldn't run it without a filter but you should replace both fuel filters. There are part numbers here on the forum to get them at an autoparts store.

 

[Seadoo rxdi]

I wouldn't run it without a filter but you should replace both fuel filters. There are part numbers here on the forum to get them at an autoparts store.

I figured for just a few seconds wouldnt hurt anything but I guess that's all it could take to clog up some injectors too..it seems to just be a generic fuel filter that most vehicles use. I'll hook up my gauge and post my numbers. If it checks out good I'll check the air pump compression..some how..not sure how I'm gonna do that one just yet

 

[Seadoo rxdi]

Here is the inline filter I pulled out of there. I'm gonna assume this is not oem. There Is not even any part numbers on it. Just says OUT and MODEL OF JAPAN

 

[Seadoo rxdi]

Here's a pic of the gas in the tank..doesn't seem to be any particles floating around but it does look kinda yellow

 

[bdesim2]

Check the water regulator on the waterbox. A not properly operating one would cause the loss of around 4-500 rpm. Take it apart check for leaks or any pinholes in the diaphragm.

 

[jhjesse]

Fuel filter is not OEM. Replace with a wix 33095 and you will be fine there. Order an Airtex FS220 as well as a FS242 for the fuel pump while you are in there.
The previous post was where I was going if none of the other things I said to look at were the problem. Check the WCV on the water box for leaks.
TPS might be out of spec, but you would need a candoo pro to check.
Look in the air intake at the reed valves.

 

[Seadoo rxdi]

Check the water regulator on the waterbox. A not properly operating one would cause the loss of around 4-500 rpm. Take it apart check for leaks or any pinholes in the diaphragm.

So I may have 1 tiny hole in there but it's hard to tell. Idk what I'm looking at tbh. Is this bad? How do I test it? And how can this cause a 400 to 500 rpm and speed loss on the water? On the trailer it'll rev all the way to redline(only did it briefly dont worry)

 

[Seadoo rxdi]

I just got done pumping out all the old fuel and putting new 93 octane in, changed inline fuel filter and took off the filter to insert my fuel gauge. I am getting 27 without running. Once started It bounces between 90 and a bit past 100 on IDLE. if I rev it up even slightly and hold it, it pegs out my gauge and holds steady. Gauge only goes to 100psi. This leads me to assume my fuel pump and air pump are working properly.

 

[Seadoo rxdi]

Here are the raves. Look fine and intact to me just very oily. I'll clean them up but would this have anything to do with my rpm and speed loss? I wouldn't think so but I'm not too savvy on 2 strokes

 

[mikidymac]

You need to get the correct gauge as you have to verify it is at exactly 107 psi when running.

Reving it on the trailer tells you nothing.

And your water regulator diaphragm has a hole in it causing your loss of rpm. Get s new diaphragm and spring clamp or safety wire.

 

[jhjesse]

Raves look good. WCV not so much. Fuel pressure is probably close because it runs good, but I would check it anyway with a new gauge.
On the WCV as stated above I would get a new diaphram. Also think about maybe using a zip tie on the WCV overhaul.

 

[Seadoo rxdi]

You need to get the correct gauge as you have to verify it is at exactly 107 psi when running.

Reving it on the trailer tells you nothing.

And your water regulator diaphragm has a hole in it causing your loss of rpm. Get s new diaphragm and spring clamp or safety wire.

Is it normal for the gauge to be bouncing a bit on idle but steady when rpms slightly increase? The gauge numbers stop at 100 but the needle can keep going past it a bit. Looking at the others numbers on the gauge it has to be at 107 for sure when just barely increasing revs. I will try and get ahold of a higher reading one tomorrow though and post a few pics of first connecting lanyard, cranking but not firing (will unplug coils and injectors),and finally running on idle.

 

[Seadoo rxdi]

I'm still trying to wrap my head around exactly what the water regulator does besides control water flow to exhaust. Ive been reading up on it but just can't understand. Does this thing have to be adjusted once taken apart and reassembled? How does this cause a loss of rpms? And does it do damage to anything by not operating correctly? I've read someone using rtv silicone to seal up the pinhole in the diaphragm. Thoughts on that?

 

[mikidymac]

Just get a new diaphragm and spend the $30. Don’t bandaid a problem.

It dries out the pipe at high rpm changing the sonic wave in the pipe and tricking the engine into thinking it has a larger pipe for more rpm. It is a 2 stroke so it’s like changing the expansion chamber to a rev pipe and is a very cool way to get another 500 rpm out of an engine while still getting good bottom end.