XP 717 problems

[Adzy110]

Hey everyone, so i bought 2 skis a few years ago, both in parts and one is together and working however it has problems. It is a 1995 SeaDoo XP 717 (720) and the problem is as follows. It will start perfectly fine and idle, but once i hit full throttle it will rev out to around 7k rpm and then die for a few seconds and it will only rev to around 4K at about half throttle, anymore throttle and it dies again. After riding for a few seconds i can hit full throttle for again for about a second before it dies again. If i get the throttle in the right spot and the choke partly on, it will comfortably sit at 6k no worries. To me this seemed like fuel starvation so i have pulled the carbs apart and put all the best parts out of these carbs and the ones from the other ski i got. Still had the same problem so i installed an electric fuel pump and its still doing the exact same thing. The ski has a new MPEM and new spark plugs. Yesterday i pulled the carbs apart to check the jet sizes. The pilot jet is a 70 (67.5 stock) and 135 main (135 stock). Does anyone have any ideas? Also the engine was rebuilt by the previous owner this oversize pistons but i dont know how big

 

[Mickirig1]

DO NOT RUN THAT SKI ! The fuel brings oil to the engine. When you run lean, it is not getting enough OIL to the working parts. Use the search function to read about fuel problems and tests you need to do. Off hand I would say you need to do pressure test on fuel system. Read about carbs and the filter in it. Your carb probably needs clean real good and new parts installed. Repair manuals can be found for free on the Internet.
Do not fly blind on repairs on these machines! They are high strung machines that are engineered to get the max performance out of the machine. READ READ READ here to learn about these critters.

 

[Adzy110]

Thanks mate I'll see what i can find

 

[mwat65]

Have you changed the rectifier? It will sometimes act like fuel starvation if the rectifier is bad. The 720 rectifiers don't go bad as often as the 800s but they do sometimes go bad. Also a weak stator will do the same thing if it isn't properly charging your battery. As the battery gets weaker you will lose Rpms. Is your battery good ?

 

[Matt Braley]

Only 1996 787's have the rectifier problem. Others failing is random and do not cause the same symptoms. Those symptoms are different from these though. I agree that it's a fuel starvation problem.

You need a pop off tester, 20 feet of 1/4" automotive fuel line, a fuel valve, 2 OEM carb kits and needles & seats. Your fuel filter can be washed with soap and water but needs to be replaced it the screen tears obviously.

Now you can follow the steps in the carb sticky and achieve a perfect running ski. It's a great model and worth saving for sure.

 

[Adzy110]

cheers for the replies. That's where i was heading next, although i did find bigger jets in carbs from the xp 800 i have that doesn't run so i was going to try that before spending any more money just yet. I dont have the highest hopes for this working but its free so may as well try it

 

[Mickirig1]

You have to remember that the systems are all tuned to work together. The air box regulates the air flow,the carb jets, the fuel flow. So one changes, the other needs adjusted too. Does it have the factory air box? That can be a problem too. The carb needs cleaned well and new parts and seals replaced. It's a 95, may never been touched. Pop off needs checked. OSD.Com has a $25 tester. You just need a bike air pump to power it. They have carb kits with all the parts. Like I said you need to read,read,read and ask questions. It's easier to suck air the fuel. You have a fuel delivery problem.

 

[Adzy110]

yes it does have the factory air box. Only problem with living in Australia is everything for these jet skis are about twise as much as they would be for you in the states.