02 GTX DI Bogging

[ecpunk]

LONG TIME lurker, first post.

My 2002 GTX DI was running awesome until about a month ago. It has 230 hours on it, and I've always kept maintenance up on it - I have the shop manuals and follow a lot of the suggestions from this board.

I put the ski in the water after filling up with 100% gas, and it ran great for a half hour, then bogged and died. It started right back and slowly started to run rougher and was turning less and less RPMS (all of this happened within a minute). It quickly was running so poorly that it would start and idle for about 5 seconds, then die. I let it sit and took it out the next day to work on it. Ran great for 3 minutes, then the same quick loss of power and 5 second intervals that it would run.

I pulled the plugs, totally fouled (BLACK). I pulled the fuel rail and checked things. I soaked the tips of the injectors and cleaned them. The rave valves are nearly polished, plugs were replaced, fuel pressure 107, cylinders 123 each. Ran it again, same thing... 3 minutes of run time, then bleh. Fouled the plugs again in that short amount of time.

At no time did I get an alarm or limp mode.

I took it to a place in Knoxville, they plugged up and saw some fuel rail related codes (wish I would have asked for specifics). They said that an o-ring on the fuel rail was in rough shape, so for $215 they replaced it. Apparently shop towels have gotten expensive. Got it home, same thing. Ran like crap. Took it back, and they said the stator was not putting out full output - quoted me $1100 to replace, so I did that one myself easily. One phase of the stator was reading 1.1ohm, so technically out of spec. I did the math and it would have pushed the output down considerably. Ski still ran the same - glad I didn't pay the $1100 for the dealer to replace.

I took it to another shop. Plugged up the computer, said an injector related code would pop occasionally, but the ski never ran bad on the trailer. He cleaned the injectors with cleaner, so not a true clean and balance/check, and the codes stopped popping. Ran great. The 100% gas smelled funny, which had only been in the tank for 3 weeks, and came from a very new and reputable gas station... but I had him drain it anyway. Ran FANTASTIC for 3 minutes. It actually turned more RPM's than it ever had, and I gained about 3mph, which was awesome. Until it loaded up and fouled the plugs and ran like junk again.

The last shop said that the injector cleaning may have been just enough of a fix to get it going. I can't understand why I can run it for 3 minutes every time until it is good and warm, then it sucks wind. The thing ran fine for the mechanic for 15 minutes with no load.

I've considered buying a used rail/injectors/etc for testing - new injectors are $250 each, and I can get a used setup from ebay for $200. I'm not sure how reliable some used equipment would be, but I may determine quickly if something is right/wrong.

I'm at the guessing stage now, so any help or suggestions are greatly appreciated.

 

[Fosta]

Im also have running problems with my DI but mine are slightly different, mine is hard to start then it runs like crap for 10 minutes then I get around 1 minutes of awesomeness! then it starts running like crap again and if turned off it wont start back up again!

if you suspect injectors then I would get them cleaned properly by an injector cleaning specialist, I think its called ultra sonic cleaning (don't hold me on that just what ive read on car car forums) .

I wish you the best of luck with this as I know myself its very frustrating!

 

[ecpunk]

I've considered the injector cleaning, but wasn't 100% sure if a normal automotive injector operation was set up to clean the SeaDoo injectors. I really don't know if the orbitals are fundamentally different from an automotive injector. Maybe someone else can weigh in on that. Thanks for the suggestion!

 

[jhjesse]

LONG TIME lurker, first post.

My 2002 GTX DI was running awesome until about a month ago. It has 230 hours on it, and I've always kept maintenance up on it - I have the shop manuals and follow a lot of the suggestions from this board.

I put the ski in the water after filling up with 100% gas, and it ran great for a half hour, then bogged and died. It started right back and slowly started to run rougher and was turning less and less RPMS (all of this happened within a minute). It quickly was running so poorly that it would start and idle for about 5 seconds, then die. I let it sit and took it out the next day to work on it. Ran great for 3 minutes, then the same quick loss of power and 5 second intervals that it would run.

I pulled the plugs, totally fouled (BLACK). I pulled the fuel rail and checked things. I soaked the tips of the injectors and cleaned them. The rave valves are nearly polished, plugs were replaced, fuel pressure 107, cylinders 123 each. Ran it again, same thing... 3 minutes of run time, then bleh. Fouled the plugs again in that short amount of time.

At no time did I get an alarm or limp mode.

I took it to a place in Knoxville, they plugged up and saw some fuel rail related codes (wish I would have asked for specifics). They said that an o-ring on the fuel rail was in rough shape, so for $215 they replaced it. Apparently shop towels have gotten expensive. Got it home, same thing. Ran like crap. Took it back, and they said the stator was not putting out full output - quoted me $1100 to replace, so I did that one myself easily. One phase of the stator was reading 1.1ohm, so technically out of spec. I did the math and it would have pushed the output down considerably. Ski still ran the same - glad I didn't pay the $1100 for the dealer to replace.

I took it to another shop. Plugged up the computer, said an injector related code would pop occasionally, but the ski never ran bad on the trailer. He cleaned the injectors with cleaner, so not a true clean and balance/check, and the codes stopped popping. Ran great. The 100% gas smelled funny, which had only been in the tank for 3 weeks, and came from a very new and reputable gas station... but I had him drain it anyway. Ran FANTASTIC for 3 minutes. It actually turned more RPM's than it ever had, and I gained about 3mph, which was awesome. Until it loaded up and fouled the plugs and ran like junk again.

The last shop said that the injector cleaning may have been just enough of a fix to get it going. I can't understand why I can run it for 3 minutes every time until it is good and warm, then it sucks wind. The thing ran fine for the mechanic for 15 minutes with no load.

I've considered buying a used rail/injectors/etc for testing - new injectors are $250 each, and I can get a used setup from ebay for $200. I'm not sure how reliable some used equipment would be, but I may determine quickly if something is right/wrong.

I'm at the guessing stage now, so any help or suggestions are greatly appreciated.

From the description of the plugs is sounds like fuel is not atomizing properly. Have you checked the air pressure from the air compressor? Should read about 80psi. With 230hrs the air compressor piston and rings could be worn and need replacing. Also possibly the air injectors are clogged.

 

[ecpunk]

I have not tested the air pressure, but agree based on the plugs that it is getting plenty of fuel... just in blob form rather than a mist.

I've never checked the air pressure, nor know how to do that. I can look it up though and will check. I'm fairly certain the air injectors appeared to be in clean shape upon visual inspection. I will look at them as well and get a better idea if I can clean/service them anyway.

Thinking about this some more, it makes sense that if the fuel injector is doing sub par, that there would be the eventual buildup of fuel causing the foul and bog. Upon letting the ski sit for a few seconds, excess fuel would evaporate, and the ski would run for a few seconds. I think this is feasible to explain the symptoms.

Thanks!

Former load augmentee at Ramstein! Loved the flight line. If I only had 3' of it right now.

 

[Fosta]

yeah my plugs are also black but I just guessed that was due to the oil getting at them. how do I check the air compressor and where is it located?

thanks fosta.

 

[ecpunk]

**Bad info here. I pointed you toward the regulator, not the compressor**

If you're looking from the side of the ski from the left side, you can see a green thing with tubes running in and out of it tied to the hull of the ski, just above and to the left of the fuel rail. That is the air compressor. No idea yet how to check it.

How do you ever get on the water in Sunderland? I was in Hull last year and it was freezing... only thing good about Hull was Grimsby chips

 

[Fosta]

Ha ha ha it's actually quite warm this time of year plus I wear a wetsuit lol

 

[Fosta]

Is this not normal for plugs in our skis?

 

[ecpunk]

Usually that nice brown color is ideal in higher performing two strokes if you have just held it wide open and then killed the motor. On bikes at least, they call it a chop test. How long have they been in the ski?

A fouled plug will be a nasty black color, and usually will remain pretty wet after running the engine for a minute or two.

**I gave some bad info earlier about the air compressor. I was thinking the regulator in my head for some reason. I honestly do not know much about the compressor other than it is driven by the engine itself. I think the counterbalance shaft.**

 

[ecpunk]

With the ski hooked up to a hose and 50 degree water pumping through it, it ran perfect at idle to 4000 rpm (mixing it up) for 5 minutes. The output water never actually warmed up, and it died. The entire engine was cool. It would crank and start for 2-3 seconds and die. I let it sit for 3 minutes, and it started back up again and ran for an entire minute and I killed it and pulled the plug. It went from being a new plug when I started to black and very wet - sooty too.

That being said, someone mentioned the compressor. The braided air hose was about 130 degrees when the ski was running while the engine was ice cold. It got hot very quickly, which may be normal, I don't know. I pulled the top off of it and.... it had a pretty good layer of water/oil mix in it, in the air line, and into the fuel rail!!! What could be allowing water and oil to mix for one, and how is it getting into the top end of the compressor?

 

[Fosta]

With the ski hooked up to a hose and 50 degree water pumping through it, it ran perfect at idle to 4000 rpm (mixing it up) for 5 minutes. The output water never actually warmed up, and it died. The entire engine was cool. It would crank and start for 2-3 seconds and die. I let it sit for 3 minutes, and it started back up again and ran for an entire minute and I killed it and pulled the plug. It went from being a new plug when I started to black and very wet - sooty too.

That being said, someone mentioned the compressor. The braided air hose was about 130 degrees when the ski was running while the engine was ice cold. It got hot very quickly, which may be normal, I don't know. I pulled the top off of it and.... it had a pretty good layer of water/oil mix in it, in the air line, and into the fuel rail!!! What could be allowing water and oil to mix for one, and how is it getting into the top end of the compressor?

View attachment 27052

Yeah ive been reading up for the last 3 weeks trying to work out what my problem was with mine and the only thing that i could see being the cause was this! Water in the air compressor. This explians poor running and small water droplets on my rave valves. Im going to finally take mine apart and i expect to hav the exact same problem.

 

[jhjesse]

ecpunk
Disconnect the air hose from the fuel rail. It is the one that comes into the fuel rail from the PTO side. Put a pressure gauge on it and crank the ski over. Should build to 80psi. If no air pressure then trace the hose down on the right hand side of the motor beside the PTO. What the hose goes into is the air compressor. Inside the air compressor is a small piston and rod that bolts to the end of the counter balance. The piston, sleeve and o ring is probably worn and will need replacing. You will also need to clean your fuel rail really good. DI's don't like water.

My son is a C-130 Loadmaster at Dobbins AFB in Marietta, GA. He loves it!

edit: Put your plug wires on the grounding posts before cranking.

 

[ecpunk]

ecpunk
Disconnect the air hose from the fuel rail. It is the one that comes into the fuel rail from the PTO side. Put a pressure gauge on it and crank the ski over. Should build to 80psi. If no air pressure then trace the hose down on the right hand side of the motor beside the PTO. What the hose goes into is the air compressor. Inside the air compressor is a small piston and rod that bolts to the end of the counter balance. The piston, sleeve and o ring is probably worn and will need replacing. You will also need to clean your fuel rail really good. DI's don't like water.

My son is a C-130 Loadmaster at Dobbins AFB in Marietta, GA. He loves it!

edit: Put your plug wires on the grounding posts before cranking.

Pulled it apart. Doesn't look great . I was reading about getting the piston out, and it looks like I have to pull the flywheel. Fun. I took the bolts out of the compressor access panel and there is no way to squeeze it by the flywheel, so I can't pull the rod/piston out. I'll see if I can figure out the easiest way to pull the flywheel - either unmount the engine or pull the driveshaft out the back.

**edit** PTO coupler is what I'm referring to pulling off.

 

[jhjesse]

Hopefully you can fix for cheap.

http://www.watercraftsuperstore.net/sea-doo-shim-pack-gtxsc-sportster-rxp-4tec-2002-08.html

 

[ecpunk]

Hopefully you can fix for cheap.

http://www.watercraftsuperstore.net/sea-doo-shim-pack-gtxsc-sportster-rxp-4tec-2002-08.html

That is a really good deal on the compressor rebuild compared to what I have found. Thanks for the link!

I have decided that I am going to pull the motor tonight and clean everything up/etc. I want to find out how the oil/water was mixing into the air compressor chamber. I know that water circulates around the head of the compressor, air is brought in the large black hose from **** (not sure) and maybe oil comes in from the crank/eccentric. I'm thinking the rings are bad (oil on TOP of the piston), the head is cracked, who knows. It has to be something fairly catastrophic for there to be air/water/oil all mixed together though. I'll let you know what I find.

 

[ecpunk]

I'm putting a parts list together. It looks like I had a small failure in the head gasket AND in the rings...

Does anyone know a good place to source the 4.3mm hose to the rave valves. I think $10 per meter is kind of excessive.

 

[jhjesse]

I think you can use 3/16 hose and it can be purchased at just about any Home Depot, Lowes, Ace hardware. It's been a while since I replaced those hoses, but I think that is what I used. It was like 5 bucks for a 10ft roll...or something like that.


Edit: Found some with 0.177" I.D.
http://www.homedepot.com/p/Watts-5-16-in-OD-x-3-16-in-ID-x-20-ft-Clear-PVC-Tubing-SVFD20/100181788

 

[ecpunk]

Engine was toast. 120PSI per cylinder, scored walls. I had SES rebuild it. I was pretty sure this was not the cause of my issue, but it needed to be done to ensure I was diagnosing one issue. I had the classic fuel pressure issue. Works great on the bench, dies out after a minute or so ONLY on the water under load. Engine would shut off, no code, no bogging. New Highflow pump totally cured it. I also installed a permanent fuel pressure gauge in the glove box. Ski runs great now. Thanks for all the help.

 

[donkey]

glad you got it sorted out! do you have a part number for the pump you put in?

 

[racerxxx]

That's cool, can you post a pic of the gauge set up? I'm sure some other members would like to see/duplicate it. Congrats on keeping the ski alive!

Sent from my SGH-T889 using Tapatalk

 

[ecpunk]

HFP-342DI is the part from highflowfuel.com. It is a perfect fit, and as others have said, they added a stainless reinforcement tube for you, so it's plug and play - I did have to solder in the pig tail, but that took 2 minutes.

Concerning the gauge setup, the ski is on the floating dock right now, but I need to pull it out tomorrow to change the oil pump flow. I will take pics then.

About the oil... I have done 0 research on this, but it appears to be true. I was told by SES that the oil pump moves little to no oil at the stock setting. This may be a well known thing, but I took dude's advice and you can shorten the oil pump cable on the throttle body end of the cable - same as you would a bike hand brake. Anyway, you can see oil trickling through at idle now, whereas before it was dead still. I think no oil is bad, and I idle at all the no wake zones. There is an alignment mark on the front of the pump, and I'm a 1/16 past it now.

Pics to come soon of the pressure gauge mounted in the glove box, but it is very loosely based on this - I modified to make it pretty and permanent:

No need for a liquid filled pressure gauge thus far - not enough vibration to matter.

 

[ecpunk]

That's cool, can you post a pic of the gauge set up? I'm sure some other members would like to see/duplicate it. Congrats on keeping the ski alive!

Sent from my SGH-T889 using Tapatalk

The GTX DI is turning into another part of my body it seems. They're quirky, but never throw one away . I will be buying another 02 later this year as I've grown attached to the model! I plan to wetsand and buff/polish the bottom this winter as well. I will re-gel and fix the larger spots. Man, this thing is much smaller and easier to buff than my other toy! I will likely also rework the jet pump as well. I change the pump oil with OE oil regularly, but the impeller has some dings in it, and hasn't been a priority.

I am seeing 6700RPM's, and gaining a little more slowly, but that has almost stopped. I think it may top out at 6750 when I dial the oil down a little and it isn't running so rich. Speed is around 54mph tops right now, but when I make the bottom into a baby's butt, I may see 1-2 mph gain there. It'll never be a speed demon, but it will be right as it can be.

My fast toy for those of you who like fast (which is a DI motor btw! Compressor, air injectors, the works):

 

[ecpunk]

That's cool, can you post a pic of the gauge set up? I'm sure some other members would like to see/duplicate it. Congrats on keeping the ski alive!

Sent from my SGH-T889 using Tapatalk

I bought the 160PSI OWG gauge from Amazon and the fittings locally at Ace.