95 seadoo xp 717 fuel problems?

[Scottmoon92]

Good morning all,
Let me get started by saying I have read 100s of post and have tried everything now I'm looking to the pros. About 3 months ago I purchased two 95 xps for a great deal and then the real fun had began. I took them out and they both ran like crap one only ran with about half choke and the other one wouldn't pick up unless I pulled the choke and let go real fast. So I started where everyone would and did a full rebuild on both carbs using mikuni parts however I did use a diffrent brand needle and seat. Both popoffs were set to 45 even though I cant find exacts on the pop off presure. Keep getting diffrent info from diffrent sites on what the actual popoff is supposed to be. For now I will just talk about one seadoo. The one where I would have to pull the choke and let go. I figured it was a popoff pressure issue so I took the carbs back off again and lowered the pop off pressure by putting in a diffrent spring and brought it down to 35 this helped the issue alot and she started running much better. After a short ride I noticed it wouldn't stay at full throttle it would bog down to about 5000 rpm and I limped it back. I let it sit for 20 min and tried again and it was good till I took hard corners and it went right back to the same issue. So I checked the voltage everything seemed normal wouldn't go over around 14.5 so I knew the voltage regulator was good. I took the carbs off again and made sure all was good which it was. I then decided to pull the fuel tank clean everything including the fuel selector and put everything back together. The ski ran much worse at this point it would rev up fast and hit a plain fast then bog down and almost die. So I bypassed the fuel switch and the fuel filter by plugging in the reserve directly to the carbs for a TEST it ran much better guess I'm getting air from there. It didn't want to pick up well but would go to full speed and hall ass again. However after 20 seconds at full speed it cuts back fast and acts like its overfueling pulling the choke makes things much worse and once I slow to a idle I can do it all over again. That's where it currently sits. This ski is running premix due to someone breaking off the oil pump cable that connects to the carb. I did do a janky fix to hold it on there but incase it breaks again I would rather run oil rich then lean so it's my temp fix. Unless that's what's causing my problems. Compression test at 130 and 135. I also replaced the upper exhaust gasket the one on top due to leaking water and cleaned the round donut copper one and put all back together. I did have a slight oil leak only when out of water coming from the PTO shaft but it has gone away since I have been testing. Sorry for making it long but I have been reading and reading and trying new things figured I would try and cover everything without having to reply a million times. Also forgive the punctuation I typed this out on my phone. Fyi the other ski is in the exact same boat lol
Thanks for your time,
Scott

 

[JeremyD615]

The first place to start is the aftermarket needles and seats. Replace those with OEM, and go back to the original spring. The factory popoff is high on the 95’s. The spec is 40-56psi... You also need to replace the fuel selector when you go back from your test setup. They’re really not worth cleaning, as they oftentimes leak even worse when they’re clean...

 

[Scottmoon92]

I will order in the factory ones right away I have been worried about that being the issue. However from my understanding they would only be in play for the initial popoff and to 1/4 throttle? I am going to order a new fuel selector due to both of them being bad. The person before me did a carb rebuild and used new springs to begin with and it was some knock off carb kit smh. So I don't have the originals. I have seen a few post saying the popoff pressure is high on these but the Manuel says otherwise. Seems like a confusing battle there. Another thing I noticed is one ski has 135 mains which i do believe is stock and the other has 130 mains I wonder why it was jetted down?

 

[JeremyD615]

You should have the 135 jets on those carbs. If one of them has a 130, I would suspect that someone may have replaced one of the carbs without checking the jet sizes. If they pulled one from an SPX, GTI, or an HX, it would have had a 130 jet in it.

As for the springs, I believe the 95 had the shiny silver 65g spring from the factory with a 1.2 needle. You can order replacement springs from OSD if you need them.

 

[mikidymac]

Also replace the strainer or at least the O-ring.

You have to get the correct springs in these regardless of what you want the pop-off to be.

 

[Scottmoon92]

I have bypassed the fuel filter for Testing and I cant seem to just find the springs any idea on where I can get them. Cant find them on osd

 

[mikidymac]

OSd Seadoo...80 gram springs

 

[Sportster-2001-951C-Stock]

Take note of the orifice diameter of the metering needle seats and confirm they're correct. When installing a seat, I highly recommend using a new/good o-ring.

 

[Scottmoon92]

Do I need 65 gram or 80?

As far as diameter I do believe it was correct but they were a diffrent brand already bought new ones from osd along with new jets both 135 and 67.5 because I chipped one of the 67.5s

 

[Sportster-2001-951C-Stock]

I believe most if not all 717's were specd' with the 1.2 metering seat. (Update, looks like they used 1.2,1.5 and 2.0, over the production run. That may require a different spring, depending.) The specs did change somewhat over the years depending on model and exact carbs used (single carb or dual carbs) for many of the Rotax motors, so it's wise to confirm and duplicate as close as possible.

I'm not a big fan of shooting for a range for pop-off, I feel it's either correct for the combination or incorrect. That said, what works best for you may not be perfect for someone else, I feel an experienced tuner can improve in some cases over the factory tune that was attempting to obtain decent performance within the limits of mandated emissions and certainly fuel types have changed over the years.

The Mikuni part number for the black 80g spring is 730-03033, Seadoo part number 270500267, according to my notes.

The resource compiled at this site link is fairly comprehensive and a good reference for the most part, I cannot speak for all of the info but mostly I've discovered it's correct:

Sea Doo PWC Carburetor Reference

 

[Sportster-2001-951C-Stock]

As I recall, my 717 was very well mannered with the factory tune. It may have been single carb, I don't recall exactly but from memory it was dual carbs?

 

[Scottmoon92]

Both of mine are 95s and have dual carbs. one of them "not the one I have been talking about" looks pretty stock and it has a pop off value of 45 both have the 1.2 metering valve. However I did change both of them due to leaking popoff pressures. After the rebuilds they both seem to have the exact same issue though with the power just dropping after 20 seconds of full throttle.

I ordered both spring sets just to make sure only 10 bucks wasted plus shipping.

I am optimistic about this fix just because they were running pretty well after some tinkering and the rebuild then just started to go downhill from there. But I know everything needs to be OEM so I'm headed in a good direction.
Is it possible that the fuel pick up tube could be leaking air into the fuel lines? I only lean this way because it seemed to be much worse when the petcock valve leaked and it's kinda the same feeling just can stay at full throttle for 15 seconds longer now, But like mentioned before I have all new parts on their way just to rule them out.

 

[mikidymac]

An air leak in the fuel system from anywhere will cause the issue at WOT. Fuel selector, hose clamps, fuel strainer.

 

[Scottmoon92]

Hmmmm is there a good way to test for these leaks? I put pressure into the tank and it held when the petcock was still installed but It still was a problem

 

[mikidymac]

Soap and water on all the joints while under pressure and check for leaks.

 

[Scottmoon92]

I will be trying this for sure. Sounds like the same idea for looking for a nail in a tire.

 

[Scottmoon92]

What's a good way to presurise the tank blow into the one way check valve at the top of the handle bars?

 

[Sportster-2001-951C-Stock]

Both of mine are 95s and have dual carbs. one of them "not the one I have been talking about" looks pretty stock and it has a pop off value of 45 both have the 1.2 metering valve. However I did change both of them due to leaking popoff pressures. After the rebuilds they both seem to have the exact same issue though with the power just dropping after 20 seconds of full throttle.

I ordered both spring sets just to make sure only 10 bucks wasted plus shipping.

I am optimistic about this fix just because they were running pretty well after some tinkering and the rebuild then just started to go downhill from there. But I know everything needs to be OEM so I'm headed in a good direction.
Is it possible that the fuel pick up tube could be leaking air into the fuel lines? I only lean this way because it seemed to be much worse when the petcock valve leaked and it's kinda the same feeling just can stay at full throttle for 15 seconds longer now, But like mentioned before I have all new parts on their way just to rule them out.

Yes, if it's falling on it's face like it's running out of fuel, it probably is. So anything that can starve fuel is the suspect.

I can't speak for your 45psi pop, have those carbs been rebuilt previously and do they have the original or replacement springs? Low pop isn't going to cause a flat lean top end (won't cause lack of fuel).

 

[Scottmoon92]

Yes, if it's falling on it's face like it's running out of fuel, it probably is. So anything that can starve fuel is the suspect.

I can't speak for your 45psi pop, have those carbs been rebuilt previously and do they have the original or replacement springs? Low pop isn't going to cause a flat lean top end (won't cause lack of fuel).

Thats what I have been trying to figure out, but i know i need OEM parts so that's getting done. I dont know if it's a lean issue, it feels the same but I remember pulling the choke and it didn't help at all. I'm wondering if lean or rich,and it's weird that is goes away right away and then runs normal again after 1 second of idling.

 

[Sportster-2001-951C-Stock]

My quick fuel line leak check is to remove the fuel line supply from the fuel pump on the casrbuuretor and blow back toward the fuel tank while listening for air bubbles coming from the pickup tube submerged in gasoline (like a fish tank air pump). I usually find them this way.

Otherwise, to leak check a piece of tubing plug one end off and pressurize from the other end. 5psi is more than enough, don't want to damage anything.

 

[Sportster-2001-951C-Stock]

Thats what I have been trying to figure out, but i know i need OEM parts so that's getting done. I dont know if it's a lean issue, it feels the same but I remember pulling the choke and it didn't help at all. I'm wondering if lean or rich,and it's weird that is goes away right away and then runs normal again after 1 second of idling.

There are some things that might cause it to be pig rich, just not as common as lack of fuel.

If for instance, there was no o-ring seal around the brass metering seat, fuel would bypass the metering seat and flood the carburetor and intake.

Running out of fuel - If all of the fuel is gone and the fuel lines are completely empty, even pulling the choke doesn't provide more fuel.

 

[Sportster-2001-951C-Stock]

OEM parts are the correct parts, assuming someone hasn't swapped them for something inferior. I hope it the label says Mikuni, it actually is.

Some of the parts are critical, but just throwing parts at something without taking time to diagnose can be wasted money.

 

[Sportster-2001-951C-Stock]

Anyway I almost forgot to point out, the 95 XP is the same ski I owned! Man I loved that ski and still kick myself for selling it 15~20 years ago. Yes, it uses the black spring and 1.2 seat, which I calculate should be 56psi pop. ie: I'd expect to see 56psi with the top of metering arm adjusted flush with the surrounding casting using the black 80g spring and 1.2 seat.. Drag a razor blade across the chamber over the arm and see if the arm is barely contacted by the blade as it crosses over the metering arm, this is flush.

'95 XP is well documented.

 

[Sportster-2001-951C-Stock]

I'm wondering if lean or rich,and it's weird that is goes away right away and then runs normal again after 1 second of idling.

This makes me think it's lean and running out of fuel. If there was an air leak there'd be more air in the fuel line at WOT while fuel consumption is highest and it's most critical than part throttle.

I'm surprised pulling the choke didn't help though.

When you disassemble the carbs, make sure all the passages are clear, the large venturi is where fuel is flowing at WOT, could be a chunk of something is stuck in this passage. That would just be one carb doing this, the other cylinder would still be running.

 

[Scottmoon92]

My quick fuel line leak check is to remove the fuel line supply from the fuel pump on the casrbuuretor and blow back toward the fuel tank while listening for air bubbles coming from the pickup tube submerged in gasoline (like a fish tank air pump). I usually find them this way.

Otherwise, to leak check a piece of tubing plug one end off and pressurize from the other end. 5psi is more than enough, don't want to damage anything.

I will perform a leak test on it just to rule it out for sure

There are some things that might cause it to be pig rich, just not as common as lack of fuel.

If for instance, there was no o-ring seal around the brass metering seat, fuel would bypass the metering seat and flood the carburetor and intake.

Running out of fuel - If all of the fuel is gone and the fuel lines are completely empty, even pulling the choke doesn't provide more fuel.

The seats were new I put them in I had to use the old o-rings due to the new ones were to big but they felt like they made a proper seal.
I agree with running out of fuel but I also imagine she wouldn't just pick right back up after falling to idle and not even dieing such a strange occurence.

This makes me think it's lean and running out of fuel. If there was an air leak there'd be more air in the fuel line at WOT while fuel consumption is highest and it's most critical than part throttle.

I'm surprised pulling the choke didn't help though.

When you disassemble the carbs, make sure all the passages are clear, the large venturi is where fuel is flowing at WOT, could be a chunk of something is stuck in this passage. That would just be one carb doing this, the other cylinder would still be running.

That's what I have been thinking too. i have tried backing off a little to see if she would pick back up but it happens so fast I only have about 3 seconds to make a decision. This ski has really stumped me on whether or not its lean or rich conditions.