[LoganJack]

I recently purchased a jet ski, it is a 1996 SeaDoo SPX all stock with a Rotax 717. I took it out in the water today and it was running fine, felt like it was missing some top end acceleration. After riding for about 20 minutes I pulled it up onto the beach. I sit for a minute, then it started to make this extremely loud, obnoxious, ear piercing alarm noise. The speaker that it came from is under the handlebars. I couldn't get it to stop so i had to ride it back home and disconnect the battery.
Any ideas why it is doing this and wont stop? how can I fix it?

Another issue is that it was missing a little bit of low end power and a lot of high end. After riding for a little bit it lost a ton of low end and basically I was stuck putting around at 20mph on and off. Could the carb not be tuned correctly? Maybe spark plugs? Also, What spark plugs does this take?

And last but not least, im not sure that the Variable Trim System is working correctly, is this an important feature or can i do away with it?

Thanks. Any feedback will be appreciated.

 

[YamaDoo]

The alarm you heard was most likely the overheat sensor going off. Was it hot under the seat? The very first thing to check is your compression it should be 145-150psi. Then work your way to the fuel system. Does it have the original grey tempo fuel lines. If so those will need to be replaced as they turn into a green slime on the inside and can clog your carbs.

 

[LoganJack]

The alarm you heard was most likely the overheat sensor going off. Was it hot under the seat? The very first thing to check is your compression it should be 145-150psi. Then work your way to the fuel system. Does it have the original grey tempo fuel lines. If so those will need to be replaced as they turn into a green slime on the inside and can clog your carbs.

No, it was not hot under the seat. It kept ringing even after we let it sit to cool down just in case. But the alarm kept going off. We took out the battery so it would stop, then we put it back in later and the ringing was slot more quiet, then it just stopped. Could it be a bad sensor?

 

[YamaDoo]

No, it was not hot under the seat. It kept ringing even after we let it sit to cool down just in case. But the alarm kept going off. We took out the battery so it would stop, then we put it back in later and the ringing was slot more quiet, then it just stopped. Could it be a bad sensor?

Could be. Did you feel the engine to see if it was hot. It should ideally not be more than just warm to the touch.

 

[LoganJack]

Nothing other than the usual heat. It was pretty cool. Of course the exhaust made thengine compartment really warm. I thing the alarm may be broken?

 

[bmwbirdman]

Loud noise

I had the same alarm problem with an SP one time and I found that it was a bad temperature sensor. It sits right between the 2 spark plugs on the head and you can easily unplug it which is a lot easier than pulling the battery. The missing is probably either bad gas or bad spark plugs or both. Your plugs should be NGK BR8ES if it is same as most Seadoos of that year.