93 spx will not stop running

[oldwill]

Hi everyone. I have done tons of research and tackled all kinds of issues from info on this site. I have done all my preventive maintenance and then some from info from here but have finally run up against something I need some help on.
Here's the problem. 93 SPX has been running fine for years, no issues. Took out to lake, ran fine for 4 separate trips. Each trip stop ski with kill button. On 5th trip, ski ran normally came in to shore, tried to shut down with kill switch on handle bar, nothing happen, Pulled lanyard, nothing happened. Jump off ski, took off seat and pulled a plug wire (got good shock as I was standing in 3 feet of water, did not think to just pull choke. What ever doesn't kill you makes you stronger but pulling choke much better option although family got a good laugh) Restarted ski, same issue, had to use choke to stop. Removed lanyard, engine would not turn over so lanyard switch works. Place lanyard on and pushed kill switch and tried to start engine, would not turn over so kill switch works.
So where do I look now. Am I having a lean fuel condition that just started on that trip? Is it the MPEM? Replaced MPEM early this year for a Rev limiter issue, no spark, fixed problem and have had no issues till now. Have used the ski for at least 30 trips this year. I have another 93 ski that I could swap MPEM, but will wait to see what you guys have to say before doing. Thanks

 

[JJinSC]

Sounds like a lean runaway. When is the last time the carbs have been cleaned? Also if cranking back up right and experienced again then this could be an air leak.


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[Dr Honda]

I don't think it was a lean run-away. That's a high RPM issue. (it will take off)


On the 93... it may not have an MPEM. If it has a independent rev-limiter, then it could have gone bad. OR... the kill wire simply broke inside the steering assembly.

 

[oldwill]

Thanks for the input. The 93 has the rev limiter as part of the MPEM. After doing some research here on the site and your input I looked at a possible lean condition. A quick look at the intake side seemed liked everything was as it should be and no apparent leaks. Before a disassemble down to the intake I adjusted low speed air/fuel mixture. Seems like problem was an extreme lean condition at idle. Has been running like that for years, just not lean enough to cause a problem till now. Only time ski idled was quick start up on trailer before putting in the water and in no wake zone. Other than that ran at full speed or close to it when on the water. High speed jets were adjusted correctly and never had a lean condition except at idle.

 

[skisil]

I have similar issue with my 97 GTI. There is another post with same issue on older GTS (similar engine).

See links below. If you come up with an answer/solution, please let me know. I am ready to install a separate kill switch but not sure what circuit to install on.

http://www.seadooforum.com/showthread.php?78513-1997-gti-will-not-shut-off
http://www.seadooforum.com/showthread.php?72689-2000-GTS-717-engine-will-not-shut-off

 

[oldwill]

Update
Problem was a lean air/fuel mixture at idle. Adjusted mixture and now Ski is running normally. Didn't think it was running that lean. Always pulled plugs after use and they looked great. I guess it never idled long enough to show a lean condition. I always started them on the trailer with a shot of brake cleaner in the primer port on the intake so it always started right up. Looking back, the ski after start up would always start to run to fast at idle, just never let it idle long enough to realize it was running away and had a lean condition. Thanks again for input!