Super Jet What the heck? Hydro-lock

[Yami-Rider]

I have a 1998 SJ with 728, mild p/p, factory b mod pipe, stock waterbox(i think), Stock rear exhaust, dual cooling.

So the problem is: i was out last weekend and the ski ran great all day, i took about a 10 min break in the water sitting in my tray, talking to my buddies i ride with and when i went to start it, it was hydro locking....! How did this happen? Ran great the rest of the day was i got the water out of the motor. Had this same problem happen to me two years ago, but i thought i had it fixed, i guess not.

 

[tor*p*do]

hydro lock with lake water or gasoline?
is your b-pipe top screw open?

 

[augustaf]

Water may have entered through the x-manifold to cyl. gasket. That is usually just enough to get plugs wet. Maybe water entered through air filters?

 

[Yami-Rider]

hydro lock with lake water or gasoline?
is your b-pipe top screw open?

Lake Water

Top and mid screws are close with bottom 3/4 open.

Water may have entered through the x-manifold to cyl. gasket. That is usually just enough to get plugs wet. Maybe water entered through air filters?

Water filled the cylinders while i was sitting still with the bildge pumps on, so ex-manifold is a option, current gasket is about 2 years old, but like i said it filled the motor almost full of water in about 10 min.

Is it possible me sitting in the tray had enough water pressure to fill the motor?

My buddy has the same water/pipe setup as me and he sits around in the lake all the time with no issues.

 

[Vumad]

I sit in my tray and have never had a problem. Did you shut the ski down while still traveling at a decent speed? The cooling system would still be loaded and fill some stuff up. I would check the exhaust and head gaskets. Sitting in the tray with a leaking exhaust gasket could do it.

 

[ajmps1]

It runs well? Maybe there is a crack somewhere

 

[Wakerider26]

I've done the same thing on an 07 SJ I had. I floated for about a minute, then some bubbles came up, and the motor was hydrolocked when I went to start it. Looking back, I never really figured it out, but my guess was scupper.

 

[Yami-Rider]

I sit in my tray and have never had a problem. Did you shut the ski down while still traveling at a decent speed? The cooling system would still be loaded and fill some stuff up. I would check the exhaust and head gaskets. Sitting in the tray with a leaking exhaust gasket could do it.

I was at a idle when i turned the ski off.

It runs well? Maybe there is a crack somewhere

Ya i have drag race ski's recently with simular setups and my ski usually wins. Smooth solid power all the way threw the RPMs like has always been.

I've done the same thing on an 07 SJ I had. I floated for about a minute, then some bubbles came up, and the motor was hydrolocked when I went to start it. Looking back, I never really figured it out, but my guess was scupper.

I dont have a scupper and my dual 800 gph pumps were on.

 

[Dmac80sc]

Is it possible that when you stopped the ski had some water in it. Then when you went to go sit on the ski you tilted it to the side enough to let some water get into the carbs and down into the motor?

 

[KTM434]

Did you pull the plugs to verify there was water in the cylinders or is it possibly a faulty starter or electronics cutting out while cranking and making it sound like the engine is locking up?

 

[Yami-Rider]

Is it possible that when you stopped the ski had some water in it. Then when you went to go sit on the ski you tilted it to the side enough to let some water get into the carbs and down into the motor?

The bildge area was dry, I am running dual rule 800's.

Did you pull the plugs to verify there was water in the cylinders or is it possibly a faulty starter or electronics cutting out while cranking and making it sound like the engine is locking up?

Yes i pulled the plugs and saw water in the cylinders and was spraying out of the cylinders when i cranked it over.