Seadoo xp 720 won't start back up after riding

[Seadoosxp7201]

Well guys I am so stumped... on this seadoo xp 720, runs great took it out today we had a leak in the o ring head gasket and replaced the o ring and head gasket... the carbs have been cleaned the lines have been all replaced... The fuel is new from this year.. compression is 150.. coil has been replaced.. I am stumped you can run it hard for about half an hour sometimes the lanyard pops off but it seems to start right back up.. Tell I brought it back to the dock and let it sit for couple of minutes and all of sudden it did not want to start... it turned over and did start and than dies right off when I pushed the ski out for my buddy to take ... we thought we fixed it because the o ring seal was leaking out the head well that's not the case probably was another problem.. Not sure what to do??? Anyone I am in desperate need of help to get this running by weekend I will try anything anyone ever had this problem? I'm stumped hope this helps let me know if you need to more thanks!!!

 

[Matt Braley]

Start with a 5 dollar pair of spark plugs.

 

[dieselndoo]

And don't take it to the dock..:rofl:
. Try running it on deserve after new plugs installed

 

[Seadoosxp7201]

Hello Matt, I have tried that multiple times I have spark, we had a head gasket seal that was leaking if you want to give me a call later at 714-470-3299 I can explain it better if not that's okay we have tried new plugs and still nothing it did start when we brought it back and than I pushed it out for my buddy and nothing than was within a few seconds there are different flame arrestors.. I'm not sure if the jetting and needles are not set right..

 

[Seadoosxp7201]

715-470-3299

 

[Seadoosxp7201]

I have tried that multiple times and nothing..

 

[mikidymac]

When were the carbs rebuilt last with new needles and seats? What color are your fuel lines?

 

[Seadoosxp7201]

Haven't had the needles or any of that rebuilt

 

[Seadoosxp7201]

Can you please call me Matt, 715-470-3299

 

[racerxxx]

If you have spark, you need fuel and air to complete the rest. Why not mix up s little pre mix and put some into the cylinders and see if you can get it to start? Your fuel selector switch could be bad shutting off the fuel from getting to the carbs. If you've never serviced the entire fuel system on this ski it really needs to be done. I know you replaced the lines but the selector and water separator need to be either cleaned or replaced.

 

[Seadoosxp7201]

Hello, racerxxx what are the fuel selectors? And water separator ? Just wondering where they are located I will try today would like to get it out by tmr so if you could call me later it would be very helpful. My number is 715 470 3299 Branden

 

[mikidymac]

The fuel selector is the ON/OFF valve and they go bad inside and cleaning typically makes them worse. The strainer is the big white fuel filter and the o-ring that seals the body can leak when taken apart for cleaning.

You also need to rebuild the carbs with only genuine Mikuni parts as the diaphragms go bad over time and the small passages get clogged as well as the tiny internal fuel filters. The needle and seats can leak also when worn and cause the same hard starting. By just replacing the fuel lines you only did about 25% of the fuel system service job. Do the rest and enjoy your ski for many more years.

 

[Seadoosxp7201]

Thanks a million! Gonna go through them and rebuild them!

 

[mikidymac]

I can't stress it enough, only use OEM Mikuni Parts! THe easiest way is to order everything from OSD seadoo as he sells genuine Mikuni parts and complete DIY kits.

FOr a 95' XP 720, You will need (2) carb kits, (2) 1.2 Needle and seats, (2) carb base gaskets, (1) fuel strainer o-ring, (1) fuel ON/OFF valve. I also replace the oil filter and small 3/32" injector lines when I have the carbs off.

If your carbs havent been messed with they should still have the black 80gm springs but if there is any question just order new ones for a couple bucks. A lot of people that don't know put in new springs when they buy a carb kit and don't know the kits don't have the correct springs for the older 2 strokes and they can't figure out why they don't run correctly.

 

[Seadoosxp7201]

Hello, what is the o ring? Fuel Strainer ? And what's the on off valve?

 

[mikidymac]

The o-ring is for the fuel strainer that is the big white filter attached to the hull over the gas tank. It is your fuel filter and water seperator. It needs to be cleaned and once open the o-rings typically won't reseal so you need a new one.

The ON/OFF valve is the valve you turn to go from ON-OFF-Reserve. It is the fuel valve. The internal passages get clogged and rubber parts go bad leaking air.

 

[Seadoosxp7201]

Thanks, I will try that all out I have cleaned the gas tank and the fuel pump!

 

[Seadoosxp7201]

Can you send the link? Does it sound like carb fuel issue? Guys? I have the tank out now and some dirt was in the tank? The fuel filter too the tank was really dirty ? Would any of this effect how the 720 xp runs? I have all the lines replaced still gotta go through the filters and check them out. Thanks a million Guys!! Any new info would be great planning on trying it out when it stops raining haha let me know guys game to try Anything thanks Branden!!!

 

[mikidymac]

Yes, just like I already said.... You need to go through the carbs. If your tank is full of crap and the strainer is full of crap your carbs are full of crap too. You can't cut corners on these.

 

[Seadoosxp7201]

Thanks, tonight I cleaned the tank some dirt was in it.. replaced all the lines missed a couple while back.. I cleaned the fuel selector and replaced the fuel filter and o ring and cleaned out the hose for the fuel tank.. planning on getting the carbs out and rebuilding them and getting them properly jetted with the stock air box instead of the aftermarket ocean pro flame arrestors..