2012 Super Jet Taking on Water

[SJET11]

Hey Everyone,
My super jet is taking on water at low rpms. Need some help.
The ski runs fine once the water is out, but bogs when the hull is filled with water. No water enters the hull when it is off and drains its self when at higher rpms. I would say it is about 4-6 seconds that the bilge runs at 500gph before it is empty. I can feather the throttle until it is empty and it wont cut off, but usually just run the bilge. when I take the hood off there is also smoke in there which leads me to maybe an exhaust coupler but haven't checked it.
Somewhere along the line the water is pumping into the hull rather than a leak.

Specs are:

• mild built 760 ported
• factory b-pipe
• 144 mag pump
• jet maniac water box
• dual 44mm mikuni

Any input would be appreciated. Thanks!

 

[bkspeedwerks]

run it strapped to the trailer in the water with the hood off. should be pretty obvious where your issues are

 

[SJET11]

run it strapped to the trailer in the water with the hood off. should be pretty obvious where your issues are

Good Idea. I keep it on a lift but should be able to throw some straps over it.

 

[KMN]

Sounds like a supply hose from the bulkhead to the exhaust manifold or some hose on the pipe, maybe on the head, or stinger or on the bottom of the head pipe. Check all those connections.

 

[SJET11]

Sounds like a supply hose from the bulkhead to the exhaust manifold or some hose on the pipe, maybe on the head, or stinger or on the bottom of the head pipe. Check all those connections.

Thank you! I'm hoping it is just a loose connection. Could it be the midshaft or if that were bad would it fill up just sitting in the water?

 

[KMN]

Thank you! I'm hoping it is just a loose connection. Could it be the midshaft or if that were bad would it fill up just sitting in the water?

Could be, wouldn't count it out, but run it on the lift and look around.

 

[Baja 252]

Feel the water, warm or cold? That will narrow it down. Has duel cooling been added, that's another place to look.

 

[SJET11]

Feel the water, warm or cold? That will narrow it down. Has duel cooling been added, that's another place to look.

Yes it has dual cooling

 

[SJET11]

But both spouts have water coming out so it shouldn’t be related to that.

 

[Big Kahuna]

Hook up a flush kit, turn it on (This is out of the water on trailer or work Stand)........ Look in engine bay to see if any water is leaking out of any of the waterlines or motor parts........................

 

[bored&stroked]

Bogging is probably the smoke in the engine compartment. I've fought that a few times on different ski's.
Water could be anything. Bad hood seal. Bad midshaft seal. Leaking cooling system. Cracked waterbox.
Ski looks sweet though!!!!

 

[SJET11]

Bogging is probably the smoke in the engine compartment. I've fought that a few times on different ski's.
Water could be anything. Bad hood seal. Bad midshaft seal. Leaking cooling system. Cracked waterbox.
Ski looks sweet though!!!!

Thanks!
I haven't thought of the smoke in the ski being the bogging. However, the rubber fitting between the header and expansion pipe had both of the hose clamps come loose so tightening that up got rid of the bog and most of the water but I still have about a half gallon of water go into the ski. I don't really run into any issues with it now that it doesn't bog.
I don't think it will hurt anything to run it for the summer and then tear some of it down this summer to pin point the issue and I will be more willing to change the complicated parts when it's cold out.

 

[bored&stroked]

We chased a water issue on my buddies square nose all last year. Could always see water dripping off the exhaust pipe. Never could find the issue. Then this sunday we had the hood open trying to start it in the water. Finally noticed the engine coupler was throwing the water in the hull onto the pipe. Seems like its probably the midshaft seal.

 

[Sparkplug]

You can fill the ski up with water on a stand. And start it. It will be very apparent where any leaks in the hull or midshaft are

 

[faceplant2]

I had a leak once. It turned out to be the exhaust behind the water box.

 

[SJET11]

We chased a water issue on my buddies square nose all last year. Could always see water dripping off the exhaust pipe. Never could find the issue. Then this sunday we had the hood open trying to start it in the water. Finally noticed the engine coupler was throwing the water in the hull onto the pipe. Seems like its probably the midshaft seal.

I have a feeling it is the mid shaft seal because i can’t see any water running in from the front. Just seems like all of the sudden it is there. Visually i can’t even tell the water is building up but the bilge pumps will spray water when turned on for a few seconds.

 

[be_lain]

Tighten all your hose clamps on the exhaust system

 

[Big Kahuna]

Since monday have you tried any suggestions..............

 

[SJET11]

Since monday have you tried any suggestions..............

Yeah! I ran it strapped to the lift with the hood off and looked for leaks. Saw some coming from the exhaust coupler.(which was warm) That reduced some of the water but I still have some coming in and it doesn't seem to be coming from under or in front of the engine which makes me think its the midshaft seal. I will swap it out over the winter. I have quite a few other things I want to do to it as well but I want to enjoy the few months of summer we get as the ski is running fine currently. I forgot to test if the water was warm or not that was coming in after I sealed up the exhaust. I can do that maybe this weekend if I remember.

 

[SJET11]

Tighten all your hose clamps on the exhaust system

i did this it helped with some of the water.