help 96 gsx died while running. cant start, wont turn.

[fubada]

Hi All,

Hours on engine: 170
Model: 1996 GSX 787

After about a half hour on water this Saturday, I took a 5min swim, I get back on my 96 gsx, start it up normal, open the throttle, go about 15yards and then I heard a semi loud snap/pop, and the engine dies. Can't start her anymore, wont turn, pulled the plugs still wont turn by hand, no compression in either cylinder. Can someone tell me if I am correctly assuming that this is likely a bent piston? What does it take to fix this? Do I need a rebuilt engine? How can I rule out fuses, starter, etc.

Thank you!


Recent changes:

Recently switched to another fully synthetic oil brand. From OEM to Walmart Quicksilver.

Recently had a salt water hydrolock, ran the ski about 7 hours since then.

When I bought this ski 3 weeks ago, each cylinder tested at 145-150 psi.

 

[chazdo2]

Without knowing much more I would guess you are going to have to pull the jugs and see whats what. Sounds like a piston or rings blew and is jammed in the cylinder or maybe the crank. I guess the only way to start is to pull the jugs

 

[gsxgtxman]

If you didnt get the premium Quicksilver to may have got the wrong kind for SeaDoos. Sea doo uses an low ash oil. The other brands use ashless oils marked with the TCW-3 logo. The worst thing we can do in these oil tanks is mixing oils. Using the wrong stuff and mixing can cause the oil to gel, thus clogging up the oil pump lines and causing catastrophic failure of the motor. Pull the oil lines coming from the pump to the motor, and turn the pump and see if any oil is coming out.

You say no compression? Is that verified by hearing or through a compression test.

 

[fubada]

gsxgtxman: I bought Quicksilver PWC Premium fully synthetic 2stroke oil. Matching the requirements for my SeaDoo. I did not drain the previous fully synthetic Bombardier oil, mixed the two together. I highly doubt this mixture would gel and clog the lines/pump.

Upon further inspecting the engine I discovered a giant gaping hole in it, with piston pieces scattered all over the hull

What can cause this?

 

[gsxgtxman]

Oil starvation. Running too lean. Not taken care of? Numerous things. I suppose that thing isnt rebuildable?