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JPX
07-08-08, 04:51 AM
Do you have any of these symptoms on your carbureted 2-stroke engine? :confused:
- Low revs in water with throttle all the way on
- Okay revs out of water, but low revs in water
- Bogging when going from idle to full throttle
- Surging of revs
- Intermittent or sudden cutting out of engine when at speed

Then you might have a fuel delivery problem. :o Hopefully your use of the search feature in seadooforum.com has led you here!;)

First: confirm you already put new, clean, and properly gapped plugs and confirmed there is spark to BOTH cylinders. As this only costs $2/plug and a couple of minutes, you should do this before moving on.:toetap05:

For those of you with Seadoos made in the 1990s, you should expect to have some type of carb problems if you have the original gray fuel hoses. The hose breaks down internally and the residue accumulates in the filters.

I will break this up into two approaches since not everyone is up for a full fuel system rehabilitation and not everyone is satisfied with piece-meal fixes. Choose what is right for you.


Easy, but limited chance of success guide:
1. Clean out spin on fuel filter. Make sure the o-ring is there. Don't use carb cleaner or you will dissolve the filter's fiber mesh.


http://img2.putfile.com/thumb/7/19411410446.jpg (http://www.putfile.com/pic/5983017)


2. Try running your boat on RES - this would point to a clogged fuel selector valve.


http://img2.putfile.com/thumb/6/18016301257.jpg (http://www.putfile.com/pic/8360842)


3. Remove the fuel selector valve and clean it out with carb cleaner. Blow it out with compressed air in the ON and RES positions.


http://img2.putfile.com/thumb/6/18016301264.jpg (http://www.putfile.com/pic/8360845)


4. Change to new spark plugs. You should have already done that.


5. Pull spark plug wire from boot. Trim 1/4" off the tip of the wire. Reinstall to the boot and ziptie it back on.


6. Make sure your carbs' high speed adjuster is set to fully closed clockwise (zero). Set low speed adjusters to fully closed clockwise, then turn counterclockwise specific turns to your engine. Use the idle screw to set idle speed only - do not use low speed adjusters to set idle speed.


http://img2.putfile.com/thumb/7/18523182971.jpg (http://www.putfile.com/pic/8383490)


7. Check all fuel hose connections are tight and that the check valves freely blow one way, but do not the other (one above the fuel tank and one on the side of the hull from the fuel tank):


http://img2.putfile.com/thumb/6/18016301228.jpg (http://www.putfile.com/pic/8360840)

More complicated, but high chance of success guide:
1. Remove all grey fuel hose (if you still have it) and replace with black automotive fuel hose. The grey stuff breaks down on the inside and clogs the carbs' internal filters. You'll need mostly 1/4" black automotive fuel hose (Coast Guard approved marine grade fuel injected hose is top of the line, but costly). Get 25 feet of it and about 30 stainless steel #04 hose clamps....no zip ties!


http://img2.putfile.com/thumb/6/17704360934.jpg (http://www.putfile.com/pic/8347372) http://img2.putfile.com/thumb/6/17900141041.jpg (http://www.putfile.com/pic/8354427)


2. Remove the carbs and disassemble for cleaning the internal filters.


http://img2.putfile.com/thumb/7/18301390278.jpg (http://www.putfile.com/pic/8372548) http://img2.putfile.com/thumb/6/17202184062.jpg (http://www.putfile.com/pic/8323103)


3. Better yet, plan for rebuilding the carbs


Here are some excellent resources for cleaning/rebuilding the carbs and setting them up properly:
Excellent carb rebuild guide thread by qstorm. (http://www.seadooforum.com/showthread.php?t=3495)


seadoosnipe's carb theory guide thread (http://www.seadooforum.com/showthread.php?t=4151)


Parts finder thanks to SeaDooWarehouse.com (http://www.seadoowarehouse.com/)


JPX's 1996 HX carb rebuild thread with lots of photos (my own personal experience) (http://www.seadooforum.com/showthread.php?t=4809)


- Make sure your carbs' high speed adjuster is set to fully closed clockwise (zero). Set low speed adjusters to fully closed clockwise, then turn counterclockwise specific turns to your engine. Use the idle screw to set idle speed only - do not use low speed adjusters to set idle speed.


http://img2.putfile.com/thumb/7/18523182971.jpg (http://www.putfile.com/pic/8383490)4. Clean spin on external filter, clean out fuel selector valve.


http://img2.putfile.com/thumb/7/19411410446.jpg (http://www.putfile.com/pic/5983017) http://img2.putfile.com/thumb/6/18016301264.jpg (http://www.putfile.com/pic/8360845)


5. Pull fuel baffle from the tank and check for any obstructions on the intake screen. If you have lots of junk in the fuel tank, siphon out the gas and suck out the contaminants, then refill with fresh gas. If your fuel gauge doesn't work or always shows empty, check out this link while you have everything in pieces Fix for Fuel gauge empty or light on when tank is full (fuel baffle/sender) (http://www.seadooforum.com/showthread.php?t=5826)


http://img2.putfile.com/thumb/7/18903000388.jpg (http://www.putfile.com/pic/8402942) http://img2.putfile.com/thumb/7/18903000349.jpg (http://www.putfile.com/pic/8402941)http://memimage.cardomain.com/member_images/6/web/618000-618999/618555_115_full.jpg

7. Check all fuel hose connections are tight and that the check valves freely blow one way, but do not the other (one above the fuel tank and one on the side of the hull from the fuel tank):


http://img2.putfile.com/thumb/6/18016301228.jpg (http://www.putfile.com/pic/8360840) http://seadooforum.com/attachment.php?attachmentid=595&stc=1&thumb=1&d=1215902733

http://memimage.cardomain.com/member_images/6/web/618000-618999/618555_112_full.jpg
Note: This is primarily directed towards carbuerated 2-stroke models, but the principles apply to all gas engines. Those of you more experienced in the RFIs and 4-TECs feel free to chime in so we can include those specific guides on this thread as well.

RNispiros
07-13-08, 04:46 PM
JPX, First great informational posts! Being new to PWCs, your posts are helpful and insightful. (As well as Karl's and other folks)

So for replacing the Grey fuel hoses in my 1994 GTSs, are marine grade fuel hoses all created equal or is there a material advantage to one type or another? i.e. fuel hose with an inner liner as opposed to a non-lined reinforced hose. I'll replace the tie wraps with SS hardware.

I plan on rebuilding the carbs as well as I am experiencing the difficult cold start other have posted on various threads. Run great once warmed up, but difficult to get started on a cooler morning. (Compression is good, runs and idles well once warm)

Anyway, thanks again for getting info out there and hope the answer to this post benefits others getting ready to do a similar job. :cheers:

Rich

JPX
07-16-08, 02:38 PM
Reinforced fuel injection hose would be the best, but best comes at a sgnificant cost. I would expect that even non-fuel-injected hose will last for MANY years of service even though it is neither reinforced nor lined.

Maybe in 10 years we'll all be on here complaining about how black automotive fuel hose is contaminating the carbs!:rofl:

RNispiros
07-17-08, 12:41 PM
Thanks! I'm on it. I'm replacing the hoses in the first GTS this evening. I'm rebuilding the carbs once I can locate a supplier for the kits. (Didn't find one in the parts listing above... :()

Rich

illibuz
07-17-08, 07:07 PM
my seadoo is bogging and dying when i give in full throttle, it is also backfiring. Do you think going through the carburetor will fix the backfiring or could it be bad gas?

kustomkarl
07-17-08, 07:12 PM
Replace the fuel and clean the carbs...it's a double wammy...

Karl

Nate Surveyor
07-20-08, 03:16 PM
How to remove the baffle pick up from the fuel tank?

Gads! Seems that ya hafta remove the fuel tank!

I have the steering yoke off, (thought I could pull it up thru the hole) and no cigar!

OK, I got it out. I pressed down hard on the top of the tank, Pushed foreward hard, and lifted it out through the hole from the removed steering yoke, then pushed the bottom toward the back of the Doo, and got it out. Some crud on the bottom of the fuel baffle. The fuel gauge does not work, and it appears the sending unit is shot. Gads. USED one is 30-60 bucks!

:)

Nate

Seadooski041
07-21-08, 10:13 PM
I have a 94 GTS, after i prime it a couple times, it fires right away then dies. After that when i try to start it, the engine just turn. Once I prime it again and give it full throttle the engine turns for a good 5 seconds before you can hear it finally firing. You have to hold down the starter button for another second or so after you hear that and then it fires right up and takes off normally. What could cause this? It has had cleaner through the gas, new plugs gapped at .5, new filters, and the carb has been taken apart and cleaned. Also, more recently, it has started either stalling or cutting out when going over wake or choppy water. A quick punch of the start button fires it right back up again. It is highly annoying playing in the waves and it cutting out all the time. What might cause that? (we had a full tank of gas in it).

You information above is great and I plan on follow ing your instruction, but could you give me more guidance on the carb screws and how exactly to adjust those? I am ok with motors, and can hear irregularities but have no experience adjusting screws besides my lawn mower.

Thanks alot!!

livinlarge
07-23-08, 03:54 PM
Wow,
Just joined and already have a interesting piece of trouble shooting info. The idea about the fuel selector valve is great. Thanks.

Nate Surveyor
08-19-08, 05:22 PM
Looks like a bit O' spam.

Maybe zap it with some carb spray?

:)

N

mricharde
08-26-08, 08:32 PM
Great posting- has kept me busy for several weekends.
I have a '96 GTS, replaced the old grey fuel lines and discovered the neck on the fuel tank was cracked. Checked into a new one and was told it would be replaced for free as part of a recall. That was good news!
My question- now that everything is replaced, I cant seem to get fuel flowing into the carb. Is there a recommended method to prime the system and get fuel flowing again?

Thanks!
:)

hfgreg
06-27-10, 03:07 AM
Bumping this thread.

mmhyson
07-31-10, 09:36 PM
ok this may sound stupid but is the fuel selector valve the fuel valve that allows you to turn the knob to reserve. gas on . and gas off? and where is a good place to get this valve

voodoo
08-01-10, 11:32 AM
This site, and many others have the whole thing 25bux - it can be fixed but if used in brackish water then maybe best to put in a new one.

mmhyson
08-01-10, 11:41 AM
i didnt see if for 25 bucks can someone possible post a picture of the selector valve

ssilcox
09-06-10, 02:31 PM
Does anyone have the pictures that were in the thread originally? Going to work over my 96 GTX, and the pics would come in pretty handy.

Thanks!

JPX
09-07-10, 01:13 PM
Does anyone have the pictures that were in the thread originally?

I've re-hosted the photos. So here is an updated posting on this topic with the photos:

Do you have any of these symptoms on your carbureted 2-stroke engine?:confused:

- Low revs in water with throttle all the way on
- Okay revs out of water, but low revs in water
- Bogging when going from idle to full throttle
- Surging of revs
- Intermittent or sudden cutting out of engine when at speed

Then you might have a fuel delivery problem. :oHopefully your use of the search feature in seadooforum.com has led you here!;)

First: confirm you already put new, clean, and properly gapped plugs and confirmed there is spark to BOTH cylinders. As this only costs $2/plug and a couple of minutes, you should do this before moving on.:toetap05:

For those of you with Seadoos made in the 1990s, you should expect to have some type of carb problems if you have the original gray fuel hoses. The hose breaks down internally and the residue accumulates in the filters.

I will break this up into two approaches since not everyone is up for a full fuel system rehabilitation and not everyone is satisfied with piece-meal fixes. Choose what is right for you.


Easy, but limited chance of success guide:


1. Clean out spin on fuel filter. Make sure the o-ring is there. Don't use carb cleaner or you will dissolve the filter's fiber mesh.

http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554047_medium.jpg (http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554047_large.jpg)
2. Try running your boat on RES - this would point to a clogged fuel selector valve.

http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554114_medium.jpg
3. Remove the fuel selector valve and clean it out with carb cleaner. Blow it out with compressed air in the ON and RES positions.

http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554011_medium.jpg (http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554011_large.jpg)http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554010_medium.jpg (http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554010_large.jpg)
4. Change to new spark plugs. You should have already done that.

5. Pull spark plug wire from boot. Trim 1/4" off the tip of the wire. Reinstall to the boot and ziptie it back on.

6. Make sure your carbs' high speed adjuster is set to fully closed clockwise (zero). Set low speed adjusters to fully closed clockwise, then turn counterclockwise specific turns to your engine. Use the idle screw to set idle speed only - do not use low speed adjusters to set idle speed. (717cc HX carbs shown below)

http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554075_medium.jpg (http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554075_large.jpg)
7. Check all fuel hose connections are tight and that the check valves freely blow one way, but do not the other (one above the fuel tank and one on the side of the hull from the fuel tank):

http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554113_medium.jpg (http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554113_large.jpg)

More complicated, but high chance of success guide:


1. Remove all grey fuel hose (if you still have it) and replace with black automotive fuel hose. The grey stuff breaks down on the inside and clogs the carbs' internal filters. You'll need mostly 1/4" black automotive fuel hose (Coast Guard approved marine grade fuel injected hose is top of the line, but costly). Get 25 feet of it and about 30 stainless steel #04 hose clamps....no zip ties!

http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554019_medium.jpg (http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554019_large.jpg)http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554112_medium.jpg (http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554112_large.jpg)
2. Remove the carbs and disassemble for cleaning the internal filters.

http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554072_medium.jpg (http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554072_large.jpg)
3. Better yet, plan for rebuilding the carbs


Here are some excellent resources for cleaning/rebuilding the carbs and setting them up properly:

Excellent carb rebuild guide thread by qstorm. (http://www.seadooforum.com/showthread.php?t=3495)

seadoosnipe's carb theory guide thread (http://www.seadooforum.com/showthread.php?t=4151)

Parts finder thanks to SeaDooWarehouse.com (http://www.seadoowarehouse.com/)

JPX's 1996 HX carb rebuild thread with lots of photos (my own personal experience) (http://www.seadooforum.com/showthread.php?t=4809)

- Make sure your carbs' high speed adjuster is set to fully closed clockwise (zero). Set low speed adjusters to fully closed clockwise, then turn counterclockwise specific turns to your engine. Use the idle screw to set idle speed only - do not use low speed adjusters to set idle speed.

http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554075_medium.jpg (http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554075_large.jpg)

4. Clean spin on external filter, clean out fuel selector valve.

http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554047_medium.jpg (http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554047_large.jpg)http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554011_medium.jpg (http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554011_large.jpg)http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554010_medium.jpg (http://carphotos.cardomain.com/ride_images/1/2475/1109/6185554010_large.jpg)
5. Pull fuel baffle from the tank and check for any obstructions on the intake screen. If you have lots of junk in the fuel tank, siphon out the gas and suck out the contaminants, then refill with fresh gas. If your fuel gauge doesn't work or always shows empty, check out this link while you have everything in pieces Fix for Fuel gauge empty or light on when tank is full (fuel baffle/sender)

http://memimage.cardomain.com/ride_images/1/2475/1101/6185550112_large.jpg
http://memimage.cardomain.com/ride_images/1/2475/1101/6185550115_large.jpg

ssilcox
09-07-10, 01:33 PM
Incredibly helpful. Thanks so much!

jjarrett
09-13-10, 11:07 PM
This is a great post! Now my 97 XP runs so much better. It's amazing how much blue-green crud came out of the internal filters. I was having problems with the carbs starving for fuel at high speed. The PTO carb seemed to have more of the line crud in the filter. I would like to add that you need several feet of 8mm or 5/16" tubing for the fuel lines from the pick-up tube to the fuel selector and then to the filter. I couldn't get the 1/4" tubing to fit the larger nipples.

mrwolf
01-10-11, 08:35 PM
Great Thread, i think this is what i need for my HX. I am experiancing issues with the ski starting, either from cold or warm. Once the ski starts it runs well until you stop and then it will stall or not restart. Could this be a fuel problem?

The ski has the old grey lines which going by this post need to be removed as a first then rebuild the carbs.

The ski also has compression of 120 in both cyclinders, which i think is on the low side, could this cause the starting issue?

Cheers
Matt

cbr1000dude
04-28-11, 12:01 AM
I have a 97 GTI that has been trouble free and a joy to own. It's always run fine. Well, yesterday I took it for it's first run of the year, and it ran great up to 40 mph, then bogged down and died. It restarted right away, but wouldn't take much throttle. So today I reread this thread, and got up the courage to change the gray fuel lines. Not too bad once I got the air box off, why they need 12 bolts and 6 clips is beyond me. The lines were loose, and had green goo on the ends. They had to be sucking air. Runs fine out of the water......well see.
I'll try it this weekend. If it still bogs, I'll get a carb rebuild kit.
Thanks for the info.
Edit...I checked with the Ski Clinic in Antioch, and they had a base gasket and carb kit for $60, so I took it off and replaced the internal filter and rubber parts. There were some fine particles, but no goo. It looked great for a 14 year old carb. Now I feel better about launching it this weekend. A 5 mm hex socket on a shortie ratchet sure speeds up the r and r. Also, the carb hold down bolts (6 mm hex) had some sticky sealant on them and in the holes. It came off with lacquer thinner which made reinstalling a lot easier. Not some bolts you want to cross thread for sure! I used blue loctite on all the threads.
Edit 4/30/11 We took it out to sugar Barge and launched it today.......runs great! The only problem was the wind was blowing about 35 mph! Hopefully tomorrow it will be nicer. It's suppose to be near 90 degrees later in the week! Yeah!

Brunaveli
05-21-11, 07:56 PM
I am trying to take out the carbs in my 97 XP. Seems pretty self explanitory but I am still having difficulties. Any help?

Brunaveli
05-21-11, 07:59 PM
My XP runs great and is in mint condition, but the last time I was out it was kind of bogging out a little, and when me and my friends were out whenever we were take turns riding it we would turn it off to exchange, then back on like a minute later but sometimes it wouldnt start right back up and the start button would have to be held for a little bit and give it some gas. I have read that the lines or filters might be clogged with some gunk. I am just unsure of how to take the carbs off as I am very new to this

Brunaveli
05-21-11, 08:13 PM
Can I just unscrew the 4 screws on the fuel pump to access the filter without the other steps, just to check the filter?

oldbuck
06-15-11, 02:17 AM
Can I just unscrew the 4 screws on the fuel pump to access the filter without the other steps, just to check the filter?

Just cleaned my filters today on a GSX which I think is similar to your XP - you can't get to the back carb/filter without removing the front carb. Easy job though.

Lake Anna
07-25-11, 07:22 PM
I have used the procedures below and have identified the problem as the fuel selector valve. This has been a great help. I have one question, is it possible to have the blockage at the fuel pickup at the bottom of the Fuel baffle screen that is only blocking the main pickup and not the reserve pick up. I have not pulled out the Selector valve to clean it but i see the diagnostic as identifying the blockage as somewhere between the main pickup in the fuel tank baffle and the fuel selector valve. I could not tell from the pictures what the filter/screen at the bottom of the baffle looks like. If that filter would screen anything going into to baffle then the problem would have to end up being in the fuel selector. Any help with the baffle filter would be appreciated. This has been a big help:thumbsup:

Dakota881
08-03-11, 12:38 PM
Great help thanks to all

tom.lbi
09-05-11, 01:42 PM
I have a 98 GTX , will the same fix apply and are the carbs the same?

Pau1
10-11-11, 12:23 PM
My 97 GSX had partially plugged inlet filter to the rear carb. The material I pulled out of that little filter had the texture of wool fibers. It reminded me of the old auto seat horsehair stuffing. The odd thing is that the front carb filter was very clean, so the contamination most likely did NOT flow in with the fuel. The rear carb filter was 80% full of fibers and then front carb filter was empty!

tom.lbi
10-11-11, 01:35 PM
I started to replace fuel lines with auto gas lines (much cheaper than Seadoo lines or Marine grade lines) I only did what I could do without doing anything to the Carbs. I cleaned the filters and the fuel reserve switch, this was full of gray line gunk. I took the ski out for a test run But ran great for about 20 min. than bogged down. End result fix the Carbs and try again. I did check the fuel pick up filter in the gas tank . No problem there it was clean.
After taking the carbs out and rebuilding them, I replaced all fuel lines . I got out on the water and low and behold same problem !!!! I found a great mechanic and told him over the phone the whole story.
He said It could be lack of oil ( this ski is oil injected ) I took it to him and after a top end rebuild it runs great. The cylinders and pistons were scored up very badly, causing it to cease up. (bogg down )
The oil pump quit working unknown to me, also their was a hole in the oil line. If the psi in the cylinder is not around 150 you may have this problem

suprajake
06-26-12, 08:29 AM
What a huge help, thank you! It was the fuel selector valve on mine, after bogging at WOT. While out I decided to go all the way and replace ALL the fuel lines since I had the valve out to begin with. Not sure if it was covered or not, but before you remove the valve what does work is tying a string to the screw that holds the knob on, and when you pull it through to the rear it pulls the string also, and you have an easy way to return the valve to its home when you replace it.

JPX
06-27-12, 12:59 AM
What a huge help, thank you! It was the fuel selector valve on mine, after bogging at WOT. While out I decided to go all the way and replace ALL the fuel lines since I had the valve out to begin with. Not sure if it was covered or not, but before you remove the valve what does work is tying a string to the screw that holds the knob on, and when you pull it through to the rear it pulls the string also, and you have an easy way to return the valve to its home when you replace it.

That's a great tip on getting the fuel selector valve back into the hole. For some hull shapes, this is easy to reach by hand. But your string technique would certainly help those with more challenging hull shapes - or shorter arms.

Glad to see this thread helped you out!

blauther
06-30-12, 08:45 PM
I recently went through my carbs...cleaned out all the shmeg-ma...followed the carb tricks from this site (Thank you by the way).

The ski runs and idles...didn't put it in the water to test it yet, so i don't know how well it runs.

Something bothers me about the rebuild though...On the rear carb (the one without the fuel pump) the nipple that the fuel return line attaches to is pretty well plugged. When i had it apart, i had trouble blowing through it. When i looked into the aluminum body...there was just a pin hole for fuel to pass through. I tried carb cleaner and even acid, but could get much flow through it. If i filled up the nipple with carb cleaner...then put 100lbs of compressed air to the other side...it would stop the flow of air and maybe get a bubble that would come up every few seconds. In my opinion...not nearly clear enough for gas to pass through.

Is this normal? any help would be greatly appreciated.

95 Seadoo explorer
2 stroke
Dual carbs
657


P.S. I am new to this site, and forums in general. If i posted in the wrong spot can you please get me to the right spot...Thank you.

jdtox
07-05-12, 10:51 AM
Hello all I am new to here! I just returned from the holiday weekend and started looking for solutions to my issues with my 95 SPX and it led me here.

Unfortunately I don't have it front of me, to be able to look inside to see what color the hoses and stuff are, but I just wanted to explain my symptoms and see if you think the info in this thread could help me.

It starts up fine, but wont go much faster than idle with throttle fully depressed. However, when out on the water if I catch a wave just right or if I stand on the back and bounce the machine it seems to do something that makes it go fast like normal as long as I hold the throttle down. As soon as I let off the gas it will only go slow again. I don't know whats going on when that happens, if its sucking in air or what.

Does this sound like a fuel delivery problem?

Hoosier 2001 LRV
07-10-12, 10:34 PM
This post is to thank everyone on this forum for really helping me help myself get my ski running great. I also wanted to share what I did in case in helps a rookie like me.
I read many posts that all contributed to my trouble shooting and fixing. I did find something new that may help people just short of getting into the carbs.
Recently bought my first PWC, 2001 Seadoo LRV with 150 hours. It has the 947 carbureted engine. Took it for a trial run about three weeks ago to see how it ran before our family 4th of July week's vacation. It had the classic fuel problem symptoms of hitting 5,000 RPM then drop in power, back up to 5,000 RPM, drop in power, etc.
I had already cleaned the fuel filter prior to the test. One other thing I should have done was drain the fuel but I did not. After the test I:
+ Rebuilt the raves, one had a melted rubber bellows and both had their red caps screwed down tight. I cleaned everything and used replacement kits and from SBT and then put red caps flush (I read that was the standard position)
+Bought a new fuel control valve. Unfortunately it had small fittings (about 1/4 inch) and my lines were the 8 mm lines. I did not have time to get more line. I ended up cleaning my existing fuel selector valve. I did notice that during my test drive that it ran better on reserve which I understood was a symptom of this being a potential issue. So still have original valve but cleaned up and put back in service
+Gray fuel lines. Due to my procrastination I did not have time to replace the grey fuel lines prior to vacation. Mine are ugly and no doubt part of my problem. That is my next project.
+Carbs. I bought rebuild kits from SBT. When I took off the rubber covers and spark arrestor I saw that my carbs were black and shiny. i was working till late every night and decided to not get into the carbs since they looked new. I took my tools on vacation just in case it was necessary but i lucked out and did not have to rebuild (or even clean the carb fuel filters)
+Took ski on vacation for 4th of July week. We camp on a river. I filled up with 93 octane fuel. The first day I initially had the surge problem but then by end of day it was not so bad. Day two (and 13 gallons of more 93 octane fuel) it ran even better. I could get up 6,000 rpm before losing power. By end of day two I was told by a rider they thought it was now fine. Day three (and 15 gallons more 93 octane fuel) my ski was running great. We could get up to 6,500 rpm and no surge issue. Day four with more fuel it was running fuel out at 6,800 to 6,850 rpm which I understand is what to expect. Three "large" adults full out no problem. We also pulled two people on a tube no problem. Next test is pulling up a skier.

Still a lot to do on my LRV and I understand I got lucky. I just wanted to share that using good gas may help a situation. I also used the recommended full synthetic oil.

Thanks again to everyone. I also want to promote SBT. I made a few orders to them and they always shipped same day and were great on the phone actually being knowledgeable about what they sell.

Bill

receveur
07-17-12, 01:45 PM
did anybody respond to jdtox's post? i have exactly the same problem w/ my 97 gsx.

carl1269
07-17-12, 03:55 PM
Can any help diagnose this "lack of power" and rough running issue? This is a 96 sportster with a 717 engine here is a link to the audio file. This is the 3rd engine, 3rd set of carbs. we were mired with a "neutral safety" switch that was limiting the revs, but it has been bypassed. This engine starts instantly every time, and idles well, it will barely plane with one person in the boat, and feels like it wants to go, but is starving for fuel. we have changed all the lines, filters, and cleaned everything, the screws on the carbs are set @0 and 1 1/4 respectively (no the screws are not set backwards) all the fuses in the MPEM are good, there are no restrictions on the movement of the linkage (carbs are opening all the way). If I had to put a number on it, i would say the engine is @ 70% power WOT cold. after 15- 20 min, that seems to drop to about 60% power WOT. If I have posted this in the wrong place, please let me know as i am new here.
Thanks
Carl

http://www.youtube.com/watch?v=vuRoAuADpkE&feature=youtu.be

lamajama
07-19-12, 01:46 AM
Is this fuel line OK as replacement line for the gray OEM lines?

http://www.watercraftsuperstore.net/mm5/merchant.mvc?Screen=PROD&Product_Code=714SB001&Store_Code=wcss&search=fuel+line&offset=&filter_cat=&PowerSearch_Begin_Only=&sort=&range_low=&range_high=

marioseadoo
08-12-12, 05:41 PM
To any one who might be able to help me, or the person who made this post, i have one of the problems mentioned at the beginning, that is, when i go full throtle it will run for about 30 seconds and then power gets cut off, then i try giving it gas and it just sort of floods and dies, then i have to restart it and it will turn on fine but at this point i will not be able to get the full throtle power i got on the first run. This is my first jetski, 94 seadoo xp i believe the engine is a 650cc, the guy i bought it from had aftermarket racing carbs and filters

cadyshac
08-12-12, 06:06 PM
First, thanks to those who have initiated and posted on this thread.
I am new to pwc but not new to boating or doing major mechanical repairs and maintenance. I have a 96 GTI that I purchased used for a neighbor friend. It still has the original grey fuel lines. The carb's were said to be rebuilt 2 years ago but the fuel lines are still the original ones and the factory fuel filter is the only one, no inline filter nearer the carbs (yet). The problem I am having is bogging down going from part to full throttle, sometimes even stalling. When stalling occurs it takes a lot of cranking with the choke on to get started again, so not enough fuel getting to the carbs. The factory spin on filter looks ok, not very dirty. I have not had a chance to try running in reserve yet. The flame arrestor needs a good cleaning too. I guess my question is do I have to pull the carbs to check their internal screens or can I spray carb cleaner thru them while running? or add a good fuel system cleaner, like techron, after changing the fuel lines? I should have added that the idle is pretty rough, but the first couple times out it ran fine, just this last time we started experiencing the bogging going to full throttle. That makes me thing we have run enough fuel thru it to clog the carbs? or maybe I got lucky and the clog is before the carbs?

carl1269
08-12-12, 06:42 PM
Our issue turned out to be, we think, a plug wire-boot connection issue. I was puzzled because the thing started so well- i mean instantly! to the gentlemen who has issues going from 1/2 throttle to full. Make sure your neutral safety switch isn't acting up. if you start the motor, and then UN-plug one of the wires, you will eliminate the switch. if you run fine- change the switch- if not and you are sure your Plug wires are making good contact inside the boots, and your plugs are new, then we need to look at fuel delivery. Do not put carb cleaner in the tank, or spray it through a running engine. these are 2 stroke motors, and the cleaners will cause the oil to not adhere to the moving parts they are supposed to lubricate. after you remove the breather, you should see the carb adjustment screws. the one with the caps on it should be closed, and the other out 1.5 turns or so. if you think you have dirt in the carbs, with the engine off, pull the screws and shoot carb cleaner in there. you can take the end of the carbs off where the fuel comes into the carbs, and pull the little filter out can clean it. if you are not well versed in these carbs you shouldn't start pulling them apart-anyway like everyone says, the grey lines have to go- good luck!

silver z
08-12-12, 10:35 PM
To any one who might be able to help me, or the person who made this post, i have one of the problems mentioned at the beginning, that is, when i go full throtle it will run for about 30 seconds and then power gets cut off, then i try giving it gas and it just sort of floods and dies, then i have to restart it and it will turn on fine but at this point i will not be able to get the full throtle power i got on the first run. This is my first jetski, 94 seadoo xp i believe the engine is a 650cc, the guy i bought it from had aftermarket racing carbs and filters
Its sounds like you have a fuel starvation issue imo.
Sounds like while its sitting and the bowls/lines are full it runs great until you use the fuel up. Then it runs bad because it can not keep the fuel coming.... Make sense? id check the filters/lines/carbs to make sure theres no blockage anywhere. also try running it on reserve then just on to see if there a difference.

bigdawgdw
08-17-12, 09:55 AM
i have a 97 gsx that idles and takes fuel great on bottom but surges in and out on high.ive replaced fuel lines and been thru carbs.internal filters are spotless. from reading this im hoping its in the filters or selector valve .thanks for the info

marioseadoo
08-17-12, 10:31 AM
Thank you silver z, well i decided to pull one of the fuel lines that enters the carbs and i saw a green goo, inmediately made me suspicious of ethanol eating up the inside of the fuel lines and possibly all that goo has gotten inside the carbs and this is whats giving me problems, so im getting new fuel lines and had a friend who works at a boat shop clean the carbs for me. Hopefully after this is done the jetski should run fine, im a firt time jetski owner and did rode it the first time when i went to buy it and it was great. Also i should mention the last owner told me he had the engine rebuild and has performance carbs and air filters, so if i can get any suggestions or comments on this would be appreciate it.

DEEz
08-20-12, 01:40 AM
I want to thanks those for the info they have posted throughout the site & I will post what I have done.

I have in the past 2.5 weeks cleaned the carb filter & replaced my gray fuel lines, added a inline fuel filter & replaced my float & soldiered my fuel sending unit.
I let brake cleaner soak in my fuel selector valve & then slowly applied pressured air & blew the rubber blockage out (shot out like a bullet LoL). Replaced my battery & the killswitch cord.

smirnoff
09-17-12, 10:34 AM
Great thread.....have a 1996 XP & 1998 SPX (both 800's) that started bogging/missing this season. Changed plugs & siphoned the old gas, still had issues.

Found this thread & changed all the Grey fuel hoses with Goodyear fuel line (the SPX had 5/16" fuel lines). I also pulled the fuel tanks which was simple & glad I did. Remnants of deteriorated fuel hose were floating around from the fuel return lines in both, also found a screw at the bottom of one of tanks.

1996 XP: A black tar like substance was found in the fuel baffle, fuel filter, & internal carb filters (also smelled like tar). Green slime was found at the fuel selector, along with the fuel hoses between the carb's.

1998 SPX: Grey pieces of deteriorated fuel hose were found at the bottom in the fuel filter & a plugged fuel selector, green slime was found in the fuel hoses between the carb's & also inside of the carb's.

I have never pulled the carb's before.....but, it was not that difficult. Glad I did, because this could be a routine maintenance item. I also added inline fuel filters to help prevent the carb's filters getting clogged in the future. Over the winter, I am going to fix the fuel baffles (fuse on the SPX), not sure yet on the XP (only 2 bars show).

marioseadoo
09-25-12, 04:21 PM
To JPX: what year and model did those carbs come off? i have a 94 xp 657cc and they are not even close to what mine look like. Does anyone have a 94 xp with the carbs i need to see how do the fuel lines go

smirnoff
09-29-12, 10:44 PM
Great thread.....have a 1996 XP & 1998 SPX (both 800's) that started bogging/missing this season. Changed plugs & siphoned the old gas, still had issues.

Found this thread & changed all the Grey fuel hoses with Goodyear fuel line (the SPX had 5/16" fuel lines). I also pulled the fuel tanks which was simple & glad I did. Remnants of deteriorated fuel hose were floating around from the fuel return lines in both, also found a screw at the bottom of one of tanks.

1996 XP: A black tar like substance was found in the fuel baffle, fuel filter, & internal carb filters (also smelled like tar). Green slime was found at the fuel selector, along with the fuel hoses between the carb's.

1998 SPX: Grey pieces of deteriorated fuel hose were found at the bottom in the fuel filter & a plugged fuel selector, green slime was found in the fuel hoses between the carb's & also inside of the carb's.

I have never pulled the carb's before.....but, it was not that difficult. Glad I did, because this could be a routine maintenance item. I also added inline fuel filters to help prevent the carb's filters getting clogged in the future. Over the winter, I am going to fix the fuel baffles (fuse on the SPX), not sure yet on the XP (only 2 bars show).

Also - before I replaced the hoses & pulled the carbs, I went & talked to a couple of reputable SD authorized service shops to have them quote a price. Both quoted T&M, not a fixed price, which came to $1000-$1200 in labor not including parts for each machine.....:leaving:

36cfjoe
06-14-13, 12:32 AM
Quick question...I have a seadoo SP...the basic lowest model. It has only one carb....so on the carb, which fuel line is return and which one is fuel to the carb. The lines are stacked top and bottom and not labeled on the carb.

DEEz
06-14-13, 12:37 AM
Quick question...I have a seadoo SP...the basic lowest model. It has only one carb....so on the carb, which fuel line is return and which one is fuel to the carb. The lines are stacked top and bottom and not labeled on the carb.

On my 1998 GS.
On the carb end.
Top line goes to tank ("return"),
Bottom line comes from the fuel screen filter under the hood ("fuel feed line").

VaDeerHunter
06-22-13, 09:38 AM
Okay guys, again this is the best when it comes to help for newbies. I have a logic problem or maybe just to fearful of breaking something. I have a 96 XP and I am trying to get the fuel selector off so I can clean it and can't make any headway. As for a retainer all I see is a single screw in the exterior selector switch knob and no amount of prying seems to get it to come off. Am I going about this the wrong way to get the valve off? Also I assume the internal filters in the carbs are right under the fuel line intakes and can be cleaned without having to rip the whole carb apart. Can you remove them to clean them without taking the carb off the engine? Oh one more question, are the high speed adjustment on the top or the bottom of the carb when looking from the top of the engine? And can I adjust those for more flow? What I am betting is breaking down at high speed and out of the water a lot of oil smoke, almost like its getting more oil than gas. I have cleaned the bowl filter which had some crap in it and cleaned the plugs.

Thanks,

Pat

DEEz
06-22-13, 12:48 PM
I know on my 98 GS that knob was very hard to remove off the metal its slipped over.
I broke the large plastic retainer (under the selector knob that your trying to remove) that holds the fuel selector to the hull.
I replaced both the retainer & knob (the knob ended up in poor condition once I finally got it removed LoL).

Now on my 98 GS the stock carb fuel filter is internal & I had to unbolt my carb so I could lay it over to get to the very tiny internal fuel filter.

Coastiejoe
06-22-13, 01:04 PM
Okay guys, again this is the best when it comes to help for newbies. I have a logic problem or maybe just to fearful of breaking something. I have a 96 XP and I am trying to get the fuel selector off so I can clean it and can't make any headway. As for a retainer all I see is a single screw in the exterior selector switch knob and no amount of prying seems to get it to come off. Am I going about this the wrong way to get the valve off? Also I assume the internal filters in the carbs are right under the fuel line intakes and can be cleaned without having to rip the whole carb apart. Can you remove them to clean them without taking the carb off the engine? Oh one more question, are the high speed adjustment on the top or the bottom of the carb when looking from the top of the engine? And can I adjust those for more flow? What I am betting is breaking down at high speed and out of the water a lot of oil smoke, almost like its getting more oil than gas. I have cleaned the bowl filter which had some crap in it and cleaned the plugs.

Thanks,

Pat

Single screw in center of knob. Once you get the knob off you will see the screws that hold the valve to the hull.

VaDeerHunter
06-24-13, 03:38 PM
I did finally get it all off, Blaster really helped! Strangely though, after a thorough cleaning the reserve side is fine but it seems no amount of effort or carb cleaner could get the main side to flow well. So I ordered another valve. It also looks like all the lines are newer but still the Tempo gray crap so they will all be changed to Ethanol rated fuel hose. Next project is to pull off the carbs and drop the bowls, clean them a bit and replace the inside filters. The main filter had some crap in it but not much and mostly dark flakes. At that point all that could be left is the rectifier but it seems fine for most runs then just stops, starts right back up though. Very strange thing the plugs are black not the soft brown you would expect from running lean.

Thanks,

Pat

Toyotaron
08-08-13, 10:44 PM
Thanks for the details. Helped out a nagging fuel problem I have been chasing all spring.

A B Able Truck
06-17-14, 10:36 AM
Old thread - Great info
My 98 GS has the bogs down at high RPM after warmed up issue
Question;
- Are all gray fuel lines an issue? - My fuel lines appear fairly new & look to have a black inner lining - Is there a date code or run number on the gray fuel hoses that will give a clue to age?

smirnoff
06-17-14, 08:01 PM
I had to replace all the gray fuel lines on my '98 SPX - while they appeared in good shape from the outside, you will quickly see all of the green "slime" deterioration upon examination.

lordoakley
07-02-14, 04:36 PM
I have gotten around to tearing my whole 97 GSI apart and rebuilding it from scratch, I am now to the fuel reassembly and come to find out, my hoses that were apart so I know where they go are moved on me. I remember this thread having pics of the baffle showing what goes where and id in the pictures. It seems I can see the image in google images but then it comes back here and I can't see it. Are they still available? I do not want to get the fuel lines mixed up. Any help would be appreciated. Thanks

A B Able Truck
07-02-14, 05:50 PM
Try this;

http://www.seadoopartshouse.com/oemparts/a/sea/500d8c13f87002090825868b/fuel-system

lordoakley
07-16-14, 12:58 AM
Try this;

http://www.seadoopartshouse.com/oemparts/a/sea/500d8c13f87002090825868b/fuel-system

Thanks for the pics. I have the service manual and the parts manual. but it is the individual hoses from the baffle that I need help on.

clacka
08-06-14, 12:00 PM
I was having issue with my 99 GTI and replaced the fuel lines and cleaned the carb. The machine ran like new, but now loses power randomly at full throttle.

Do I check for gunk in the fuel tank now?

LouDoo
08-06-14, 12:19 PM
I was having issue with my 99 GTI and replaced the fuel lines and cleaned the carb. The machine ran like new, but now loses power randomly at full throttle.

Do I check for gunk in the fuel tank now?

Try starting a new thread in the 2-stroke PWC section, we'll be glad to help, it's just going to get lost here.

Lou

clacka
08-06-14, 04:46 PM
just ordered a replacement fuel selector valve, only thing left. Hope that works

LouDoo
08-06-14, 06:07 PM
Closing this thread, the thread is intended for information only.

Lou