Seadoo gsx rfi

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Hello, I have a 1999 GSX RFI that was recently rebuilt. I attempted to run it premix only to realize that the rv gear needed oil which cost me two rotary gears. After hooking back up the oil system I ran it with oil still being in the gas which caused the engine to run very rich with oil and smoke a lot as the oil pump is functioning.
I carried it to the lake for a run and it started on first try. When I brought it back on shore and tried to start it i had to open the throttle wide open and hit the starter for a couple of seconds to start. After about half hour of riding it began to bog down on water.
When I pulled it on the trailer it started and is sputtering on idle but revs up to 6500rpm rather well. The rpms also dropped on idle. I then pulled the plugs which were obviously black and fouled due to oil in gas along with oil pump. My question is can too much oil and fouled plugs cause it to suddenly bog down in water and sputter on idle when on trailer??
also, my fuel gauge stopped working which is causing a long beep while riding. I know on Cab models the fix is the f1 chip but how do I go about fixing it on an rfi??

Any help/feedback would be much appreciated
You can't run premix on an RFI ski. You might have caused the injectors to either stick or clog. The fuel baffle is the same fix as the carb model on this hull. You need to pull the steering out, unstrap the tank and shift it forward to slide the fuel baffle out through the steering. Then you'll either find the float dropped out, or it's not floating or the little F1 fuse internal popped. With the float sliding in the baffle you'll be able to test it as good or not before you put it back on the ski.
Thank you for replying. I solved the problem with the fuel gauge and the sputtering/ bogging. I put clean gas in tank and the fouling problems went away. The only problem right now is hard starting in water. When the engine is cold it would start in water no problems but once engine heats up I would need to crank forever to start unless I expose the exhaust to air. Once engine starts it would run great until I shut off again. Any ideas?? Can it be dirty injectors due to having oil in gas or can it be the rv clearance??
Do compression check first which is likely your problem but you could have a rotary valve issue. If there is too much clearance it will be difficult to start. Good Luck with it !
Compression is 125/130. Is that acceptable?? Also I’m going to check the rotary valve but what would be the easiest way to solve a rotary valve problem? Can I just purchase a new valve and hone the cover? Or should I change the cover as well?
Your rotary valve itself may be good but you'll find out when you remove it. Generally I find the cover is worn. I have a lathe at home so I machine the cover. Here is a picture of how the Rotary valve covers wear and you can see how a test of the valve clearance can deceive you. If you don't put the solder in the most likely places to check the true wear you will get a reading that says, "nothing to see here, all is well." :D This first cut I took was probably 005" or so and you can see it has a lot more to go to clean up completely. Probably better to buy a good cover. This is a bit of a pain in the azz but I have a lathe and would be foolish in my mind not to use. it. :D Good Luck.

Rotary Valve Cover Machine (2).JPEG
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With readings like that, if you trust your gauge, I'd do a top end without question. The engine simply will not last with those readings. It's crashing, just hasn't burnt yet. LOL
Oh well guess I’ll be doing a top end soon. When u talk about solder, what are u referring to?? And also, will bad compression cause poor performance, because she runs great once started.
What’s confusing is that this engine has 100 hours and already requires a top end. I know top ends are usually done at 200+ hours. What can be the cause of that?
Maybe your gauge is not reading correctly? You can pull the head and have a look. You never know what happened unless you look. The longer you run it the worse it will get and the more damage it will do. Instead of a top end you could be looking at a crank replacement.

If you didn't do the fuel system or injectors you could have a lean condition. Best to nip it in the bud. Good Luck. Not telling you what to do of course.
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Took the rv cover down and doesn’t look too good but not too bad at the same time. Do you think this can be fixed by replacing the rv plate and honing the cover (face and outer edges)??


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When I see lateral lines that are consistent that means there is little to no wear on the cover. From the picture looks like the cover is in excellent shape to me. I can't tell about the rotary valve but if the cover is good the valve should be good also. If the rotary valve is flat, no distortion, and fairly smooth you should be good to go as is. This is a good opportunity to get the timing right were you want it.

If you remove your rave valves you can take a peek at the cylinder bore and the side of the piston. You won't see much but I've found reasons to do a top end looking through that port. LOL I'd definitely test the compression with another gauge just to be sure. As you say.. 100 hours isn't all that much time on a top end but damage can be done by improper warm up, oil starvation, running lean, leaking crank seals, etc.... Good Luck !!
Oh I thought those lateral lines were signs of wear because I was going to machine it tomorrow but I guess I’ll just change the rv plate. I’ll also try another gauge for compression.
If you have tools you can measure the depth. Should be (.103") roughly from the bottom of the o-ring groove to the surface of the cover. Gotta have special tools for the measurement. Why do you think you need a new valve plate.
It's the clearance issue that will create hard starting. Even then, I've had some damaged rotary valves and the wear you see in the picture and the ski really wasn't that hard to start. A little bit out of tolerance won't make much of a difference. This rotary valve pictured is out of my personal GTX. I didn't rebuild the engine just rode it. Ski started fine and ran good. I never could get that extra RPM up high. I'm not sure this was the problem but bad as it is, it may have contributed. This is just representative of the kind of clearance that doesn't affect starting. So if you are worried about a few thousands of an inch or a small amount of wear.... well... just look at this one. LOL 1996 GTX 787.

I had a 717 that was a little ornery starting. It needed some choke and finessing but always started without too much trouble but took 3 or 4 tries. The valve was about like this one in shape maybe not this bad... it made a huge difference when I fixed that one. Good Luck !!

Rotary Valve Bend  warped bad (1).JPEGRotary Valve Bend  warped bad (2).JPEGRotary Valve Bend  warped bad (3).JPEG
Ok thanks for all your help so far. As you said, clearance is the main problem when out of spec, so I’ll measure my clearance tomorrow and hopefully get to a conclusion.
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