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My lemon 96 GTX 787 :(

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rshaw

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Hello everyone! (tl;dr at bottom)

History:
I purchased my GTX in a pair which I went in on with a friend, a 96 and 97 GTX. I was told the 96 had a new engine (mid 2012) so I thought it would have less issues, but I was so wrong. After purchasing it need a new battery because the one it had was always flat, so that was a nice start. Go to grease it and find out that there is not grease fitting where the fitting is suppose to be! Buy one and grease it a decent amount. A couple weeks later blew a piston. Fixed the piston myself even though I've never worked on a jet ski but it turned out well and everything ran once replaced (). After that was fixed a hole in the exhaust manifold coming off the top end magically appeared - I honestly don't know how it got there - and the hole was deep enough to go into the cooling system and pump water into the hull of my jet ski. You see when I replaced the piston I didn't remove the engine out of the craft or the exhaust pipe coming off the top end and it was on the bottom of the pipe! So anyway I patched that with some marine exhaust patch stuff from Canadian Tire and seems to be holding well enough.

Today:
This year I was hoping my problems had stopped and it would just run, but it was not to be. A week ago it starts to cycle between 5500-6500 when at full throttle, so I changed the plugs and it went away for a day and then almost immediately came back. Check the plugs and they are black so I figured I'd adjust the carb's high and low speed screws. On going to do that I look and it there seems to have been a minor explosion of sand coloured liquid, with the consistency of a very thick oil, out of the oil pump! This could have only come from the oil pump as there was a spray on the lines in front of it and on the gas tank as well as dripping from the base where the pump attaches to the engine. I also noticed that the oil lines were still the old ones. Not knowing what to do or check in that area I just wiped it down and did nothing else and I haven't seen that liquid since. (I'll be replacing the oil lines tomorrow with new ones tomorrow if the weather holds.) So after adjusting the high speed and it running even worse I put them back where they were and opted for the low speed. The manual said tighten and then let off 1/4 so I did and that made it all worse with one exception - it stopped cycling between 5500 and 6500 and would mostly run at a steady 5500 sometimes dipping to 5200 and back every 30sec or so but never above 5500. Another thing that I noticed after adjusting the low speed screws was an increase in power on left turn (up to 6300rpm) and decrease on right turn (3500rpm) which wasn't happening before. Left cylinder has 120psi. Right cylinder has 123psi It also now hesitates when you go from standstill to full throttle.

That's where I am right now, I'm tired of trying random things and am looking for some advice! Thank you in advance.

Current Symptoms/Info (TL;DR):
- Max RPM 5500 and occasionally drops to 5200 and then goes back up
- Hard right turn = power loss (down to 3500prm) Hard left turn = power increase (up to 6300rpm)
- Switch fuel gauge from Fuel to RES and the ski doesn't run
- I messed with the low speed screws and am having a hard time finding where the sweet spot is again :(
- Hesitates from stop to full throttle
- After hesitation it will jump up to 7000rpm for around 2sec before falling to the regular 5500.
- Left cylinder pressure is 120psi Right side 123psi
- There was a one time sand colour liquid that sprayed out of the oil pump area and dripped down from where the pump attaches to the engine. Has never happened or leaked again. It's definitely still using oil.
 
No, had all clear lines when I bought it except for two old grey lines running off the oil pump they must have missed.
 
Gotta pull the carbs and clean and rebuild them. So if it ran last year you shouldn't have messed with the carb settings. Replace the fuel selector. You really have to thoroughly go thru the fuel system. It's the fastest way to kill a 2 stroke.
 
That ski is not a lemon, most of the issues you ststed are common Seadoo issues, especially when one has been run in salt water
 
FYI, You shouldn't just clean the carbs. You need to rebuild them with new parts as it sounds like it is starving for fuel at high RPM's.
Also your oil lines should not be gray.
 
[MENTION=53237]mikidymac[/MENTION] - I figured it be best to do a rebuild if I was pulling them off anyway so I ordered the rebuild kits yesterday, just gotta wait for them to come in. Yeah I know, I don't understand how they could replace all the lines but two. In any case I had some spare fuel line laying around so I replaced them.
[MENTION=29781]Spimothy Leary[/MENTION] - I pulled the raves and they had a ton of build up on them so I grabbed some carb cleaner and a wire brush and now they are spotless! When I tore down the engine before I didn't think to clean them because I didn't think it was a big deal but after going through some posts on here I realize it does effect performance.
 
Make sure you get new needle and seats too as they don't come with the kits and reuse your springs as the ones in the kits are not correct.
 
[MENTION=53237]mikidymac[/MENTION] - I figured it be best to do a rebuild if I was pulling them off anyway so I ordered the rebuild kits yesterday, just gotta wait for them to come in. Yeah I know, I don't understand how they could replace all the lines but two. In any case I had some spare fuel line laying around so I replaced them.
[MENTION=29781]Spimothy Leary[/MENTION] - I pulled the raves and they had a ton of build up on them so I grabbed some carb cleaner and a wire brush and now they are spotless! When I tore down the engine before I didn't think to clean them because I didn't think it was a big deal but after going through some posts on here I realize it does effect performance.

generally dirty raves won't create that surge you described, but when you mentioned 5500 rpm a couple of times it made me think of them and I thought it was worth mentioning. I still tend to think its fuel related but maybe the raves are sticking and unsticking ? (probably a stretch)
 
Make sure you get new needle and seats too as they don't come with the kits and reuse your springs as the ones in the kits are not correct.

I've rebuilt the carbs with new needle and seats and using the old springs like you said and also tried cleaning the fuel sector the best I could with some carb cleaner. What I found odd though was that after cleaning the fuel selector I ran some water through it to see if it was clear and it seemed to flow almost as good as when it was turned to fuel but when I put it on reserve while running the jet ski it would just stall out like nothing was going through it at all. I've ordered a new fuel selector to make sure that's not the problem. In the end it's working better than it was before the carb rebuild but isn't quite there yet, now it cycles between 5800-6400rpm. Anything else I can check while I wait for the new fuel selector to come in?
 
No one said anything about the 120 compression on each lung? I would recheck that and if that is correct, that is a major problem
 
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