1996 GSX bogging-pulling my hair out- FIXED-UPDATE

Will start & idle but as soon as I give it gas, it boggs, shakes @ hesitates. It used to occasionally give me trouble at the high end, so I added Seafoam (accidentally added 2x as much as should have), ran it for 10 minutes. Ran fine. 1 week later, I ran it and It would jump for a second then bogg down. I time it ran strong to 5000 RPM then cut in and out. It bogged from the get go ever since. Here is what I done so far: Took carb apart. I was going to rebuild but everything looked immaculate (including filters).
Checked in-line fuel separator (it was clean). Checked resistance between plug wires (in line with specs), checked OHM reading on coil (normal range is .3-.6) READING CAME IN AT .9. Put in new spark plugs. After 1-2 minutes of running time BOTH WERE BLACK AND WET. I also noticed small leak coming from RAVE valve(rear by muffler).
Some questions I have are: Could too much Seafoam cause my issue? ( I've read this should not) or was this just a coincidence that issue occurred when it did?
Could coil being slightly out of spec allow engine to start but not accelerate?
Could blown crank seal be the cause? ( no oil coming from cylinders when turning over w/o plugs so unlikely)
Could pop-off in carb or any of the RAVE valves cause my problems? I tried looking on internet how these may impact my situation with no clear understanding of what these things do or how they relate to my problem. If RAVE is issue, is it the 1 by muffler or 2 on engine?

I am 68 years old. The ski has been in the family for 25 years. Now I enjoy taking grand kids for a ride so hard to let go. The ski has way too many small issues that I deal with so I can't pour a lot of $$$ into it and nearest mechanic is an hour away. Any intelligent feedback would be greatly appreciated.
 
When you took the carb apart did you check the three holes to verify gas was flowing through them all? Those clog often. Do you have the low and high speed screws at factory? Read over the carb rebuild sticky on this site and see if anything stands out.

Also, higher resistance lowers current, which is not good. I would look at changing the coil out, try and use an OEM unit, aftermarket parts are not reliable.

The water valve that is leaking is not a culprit with your running issues but you should rebuild it or repair leak soon. You don't want water leaking in your hull.
 
Thank you for your reply ! I only know of the main jet & the pilot jet which were clean as a whistle. Where is the 3rd one? All screws factory set both before and after carb teardown. Thanks for clarification of water valve, (one less thing to focus on) How about any of the 2 RAVE valves on engine, any thoughts? Will most likely change out coil, however will welcome more input first, as I try to get a consensus first.
 
Try disconnecting the rectifier. I'm not sure on 1997 but there's a red wire on 1996.

It won't charge the battery but it'll run for a while disconnected. If it runs great without the rectifier you need a new rectifier.
 
Thank you for replying. Boy, I didn't see this one coming. Bad news- doesn't sound quite like my situation. Good news- seems like an easy enough test. I'll try it! Thanks again.
 
Thank you for replying. Boy, I didn't see this one coming. Bad news- doesn't sound quite like my situation. Good news- seems like an easy enough test. I'll try it! Thanks again.
With all the hell you've been through troubleshooting, it's a good and easy one to rule out. Engine bogging above 2500rpm was what mine was doing when my rectifier failed (twice now). Basically the bad rectifier either sends AC or too much voltage to the mpem which causes the engine to start missing.

Raves open around 5k rpm so if it's bogging at the 4-5k mark you could try cleaning them. But I think if they're clogged it won't bog as much as just top out at 5k instead of 7k.
 
Rectifier is a free and easy check.
My money is on the carbs/fuel system.

Also a compression check would not be a bad idea.
 
Compression is good.

You can't just "clean" these carbs.
Get the rebuild kits from OSD Seadoo and follow the Carb Rebuild Sticky.
 
Yes, That is my worry. Pulling out carb was real rough on my 68 year old back. I want to check out all possible culprits before getting down in the pit again, Thank You
 
Since you said you didn't understand the rave valves...

The RAVE valves are exhaust valves that open above around 5k rpm. If you make the exhaust valves too large then performance and efficiency are poor at low rpm, and if too small, it suffers at high rpms.

So the point of the rave valves is they're spring loaded and open at higher rpms, giving you about 20 extra hp at the top end.

They should be cleaned as part of yearly winterization. They're accessed by the plaatic covers on top of the engine. Plenty of videos on YouTube.

I don't think raves are your issue. Agree that a compression check is the next step.

Also, just because the carbs look clean doesn't mean the components aren't worn. If you do a carb rebuild, check the carb rebuild sticky thread and ONLY use genuine Mikuni.

Have you ever replaced the fuel lines or are they still the grey ones? The grey can deteriorate and should be replaced, but if they were doing that your carb filters would not be clean, so I don't think this is your issue.
 
Since you said you didn't understand the rave valves...

The RAVE valves are exhaust valves that open above around 5k rpm. If you make the exhaust valves too large then performance and efficiency are poor at low rpm, and if too small, it suffers at high rpms.

So the point of the rave valves is they're spring loaded and open at higher rpms, giving you about 20 extra hp at the top end.

They should be cleaned as part of yearly winterization. They're accessed by the plaatic covers on top of the engine. Plenty of videos on YouTube.

I don't think raves are your issue. Agree that a compression check is the next step.

Also, just because the carbs look clean doesn't mean the components aren't worn. If you do a carb rebuild, check the carb rebuild sticky thread and ONLY use genuine Mikuni.

Have you ever replaced the fuel lines or are they still the grey ones? The grey can deteriorate and should be replaced, but if they were doing that your carb filters would not be clean, so I don't think this is your issue.
Thanks for clarification on RAVES. Some posts said if they are "stuck" either open or closed(I don't remember) that could pose a bogging issue.
Compression is very good 145-153. I'll have to check out this rebuild sticky thread, however, diving back into the carb again will be the last thing I do. Very difficult for an old guy like me.
 
If you haven't cleaned your raves recently, do that. Yes, if stuck open it might make it run poorly at low rpms--honestly not sure.

But you should clean them if you haven't in years.

Have you replaced the original grey fuel lines?
 
Lothsahn, I tried pulling off red wire from rectifier to MPEM. Guess what? It ran GREAT out of water. Will order new one and hopefully will get same results on the water. A BIG THANK YOU!
 
Lothsahn, I tried pulling off red wire from rectifier to MPEM. Guess what? It ran GREAT out of water. Will order new one and hopefully will get same results on the water. A BIG THANK YOU!
Very welcome. Hopefully that's the problem... Sometimes only see problems in water!

You can run the ski for at least 30m with that wire pulled if you need to test in water, FYI. Just disconnect the battery and top it off with a charger before heading out to the water.

Did you ever replace the fuel lines? If not, you REALLY need to. Maybe enlist some of those grandkids.
 
UPDATE on fixed. Seadoo ran great a couple of times with new rectifier, however started to act up again. Instead of assuming rectifier was bad, I pulled a 4 connections and loaded each with dielectric grease. Works great again. Lesson learned.
 
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