Super Jet SN dying when putting weight in the tray(rear)?

[Vumad]

If it's a stock exhaust, it's going to have a lot of water coming out of it on the hose. There's no way to see how much water is coming out of it in the water so you must be doing it on the trailer. Running the stock motor and pipe on the hose for about 30 seconds, then hitting the throttle, it's going to dump loads of water out. It's designed to be quiet, not work good. It's probably not excessive. It's just stock.

You did not answer the question about the tilt. Does the thing die as soon as you tilt it even at an idle? Or does it die when you give it gas? Does it run okay strapped to the trailer in the water and continue running when you hit the throttle? Can you put the ski in the water, put the nose up against a sign or some other stationary object, keeping it flat and hit the throttle?

The tilt is probably not related in any other way than you have to tilt it before you ride it.

 

[hink320]

It started up right away today after sitting over night and had water pouring out the pipe after all the water got out I put a rag In the exhaust and it died so that would be pressure related? Would that be a blown gasket?

Any ski will die if you stuff a rag in the exhaust. Maybe try doing that again with the hood on and sealed tight and as soon as it dies pop the hood off and see if the engine compartment is full of smoke. That would be a good indicator of an exhaust leak.

 

[Vumad]

It started up right away today after sitting over night and had water pouring out the pipe after all the water got out I put a rag In the exhaust and it died so that would be pressure related? Would that be a blown gasket?

I bet if every time you went to exhale, someone held a rag over your face, you wouldn't run very long either.

 

[phreeride215]

Put a new one way valve on the tank vent, and drill a 5/64 hole in the bottom of the water separator drain plug.

 

[NorCalSJ]

It is dying when tilted in the water at idle but will run out of the water tilted just fine. Soon as tray is pushed down under water it starts to sputter right away and dies when load is put on motor.

 

[Tyrant1919]

I'd check everything at this point. Does it idle fine in the water? should put it on a stand/trailer somehow and put it under load with the exhaust above water.

 

[NorCalSJ]

Yeah it idles fine runs fine in or out of water but dies when put under load

 

[phreeride215]

have you tried running it on the reserve pickup? have you pulled the return line off to check for flow in the "on" position? have you worked on anything since it was last ridden? did it sit with water in the engine and freeze over the winter?

 

[phreeride215]

All you need to run is fuel, spark, and compression. if it ran before, check these things first.... fuel flow as i described, compression test, and pull the plugs and check for spark before you go chasing some crazy problem. keep it simple.

 

[Vumad]

Yeah it idles fine runs fine in or out of water but dies when put under load

Start simple and work to more complex.

Run with hood off, look for exhaust. Run with hood on, remove hood quickly, look for exhaust. If in doubt, run with go-pro under hood, look for exhaust.

Pull carb. Check pop-off. Clean all carb internals and replace what is necessary. Open up fuel pump and clean fuel filter. Inspect fuel pump for damage.
Flush fuel lines with fuel and clean petcock.

Replace plugs. Confirm spark in both plugs. Check compression.

Most of the time, the problem is somewhere in the above.

The likely hood of you ski not running because the exhaust is under the water and there is too much back pressure is very low. It is possible, but it is much more likely one of the above is the cause. You need to work on diagnosing the problem by ruling out the much more common problems. Your problem is most likely due to a boggy low performing motor.

Your jet ski is a giant weed eater. The weed eater has a clutch, so when you get a vine stuck on it, it bogs. The Skis direct drive doesn't allow the motor to bog. If the water is heavier than the power of the motor, the motor can't turn and the ski dies. They always run fine on the trailer, no load.

 

[aytee]

It started up right away today after sitting over night and had water pouring out the pipe after all the water got out I put a rag In the exhaust and it died so that would be pressure related? Would that be a blown gasket?

yea.. i didn't mean go to the extreme of completely plugging it... just put your hand over to create some resistance... not plug it... any engine will die if the exhaust is blocked completely...

maybe just get a video with sound of everything from start to kill and post it.. might shed some light one exactly what it's doing...

btw the only thing i haven't read a report on is cylinder compression... if it was me, i wouldn't waste time anywhere else until i had a gauge on each hole...

 

[Captain PegLeg]

leave the ski strapped to the trailer on the boat ramp and back it into the water where the pump is under a load, fire it up and test... this should duplicate the tilting in the water and give you a stable platform to work on. this is how i check carb tweaks, issues, ect...

 

[Quinc]

Bump! did you ever figure it out?

I had this same issue with my Blaster 1, you could even gun it and it would want to take off, but as soon as you tried to climb up the back it would die. I doubt its related but there was about 3ft of fishing line wrapped around the prop and after I removed that it worked fine. :shrug:

 

[Nemo]

btw the only thing i haven't read a report on is cylinder compression... if it was me, i wouldn't waste time anywhere else until i had a gauge on each hole...

X2. Start the trouble shooting flow chart...

 

[NorCalSJ]

It ended up being a broken reed, I know this is a really old post, but maybe it will help someone. Funny thing is my ski is now having similar issues.