1999 Sea Doo GTX RFI - Hydro-locked

[LIBoater]

Daughter 2.0 took the ski out last weekend and, this is a direct quote: "I just stopped to talk to a friend, it coughed and sputtered a bit, then it stopped and wouldn't re-start [not even crank], dad, honest" [yeah, right]... we got it back to the boat, but it would not crank (just a click or buzz from the solenoid). Based on my well-documented recent starting issues, I assumed it was the starter. However, having slept on it, I realized it could be hydro-locked. I removed the plugs and it still wouldn't crank... even by hand (turning the shaft). So, I pulled the ski and brought it home. Sprayed a healthy dose of PB Blaster into each cylinder and let it sit overnight... I then put some vice grips on the shaft and wiggled a bit and the pistons freed. She now cranks good as new, but, with the PB Blaster in the cylinders, I don't want to simply refit the plugs and start her up... as a result of this experience, I have a few questions, which I hope the brain trust on this forum can help weigh in with some answers/perspective?

1. How easy is it for these machines to get hydro-locked, what could have caused it (slowing down too fast and the wake back-washing in to the exhaust (and cylinders?), maybe?) and how can I prevent it in future?
2. What's the best way to make sure all the PB Blaster (and water) is out of the cylinders before I replace the plugs and try and start her up? Just crank and crank and crank until all the discharge from the spark plug holes stops (or reduces to mist?)?
3. I read somewhere about a magic product called "Bombardier Lube"... but I don't think it's made any more. I assume I should spray something (Bombardier Lube? Fogging Oil?) in to each cylinder to displace any remaining water and coat the cylinder sides?
4. Anything else I should consider before putting it all back together and re-starting?

Thanks in advance!

 

[mikidymac]

Sounds like your engine seized, not hydro locked.
IF it was hydrolocked as soon as you pulled the sparkplugs it would have cranked over fast and been shooting water out of the sparkplug holes.

Given the fact that it "just stopped" and you couldn't turn the engine over you have seized pistons or a crank or both. I would pull the head and look for cylinder damage.

 

[LIBoater]

Sounds like your engine seized, not hydro locked.
IF it was hydrolocked as soon as you pulled the sparkplugs it would have cranked over fast and been shooting water out of the sparkplug holes.

Given the fact that it "just stopped" and you couldn't turn the engine over you have seized pistons or a crank or both. I would pull the head and look for cylinder damage.

I got it turning over fine again (thanks the PB Blasted trick)… it Is not seized

 

[LIBoater]

Update: My local Sea Doo dealer gave me some great tips:

1. Take the ski off it's trailer (onto the grass or something soft) and tilt it 90 degrees so the head is above the exhaust (effectively laying it on its side)
2. With spark plugs removed, hold throttle wide open and turn engine over until the spitting from the spark plug holes stops (this evacuates any remaining water/PB Blaster from the heads into the atmosphere/exhaust)
3. Put the ski back on the trailer and spray a healthy dose of Sea Doo lube (see attached photo) into each combustion chamber
4. Crank a few times and repeat step 3, then replace spark plugs and start her up
5. Once you know she runs, take her out for a long, hard ride (to get all the temps up and evacuate any remaining moisture/contaminants)

She was a bit smokey, but started on 2nd crank... will take her back to the water tomorrow night and complete step 5!... thought this might be helpful for any who follow?

Cheers!

 

[mikidymac]

Ok, so if the engine was stuck and you had to use PB Blaster and a wrench to get it to turn over then the engine was defiantly seized and not hydro-locked.
If no water came out of the spark plug holes it wasn't hydro-locked.
A hydro-locked engine will crank over as soon as you remove the sparkplugs, no lube or wrench is needed.

It really sounds like it seized and you broke it free with the lube and wrench. If this is the case you will have a catastrophic failure if you keep running it.

 

[LIBoater]

Ok, so if the engine was stuck and you had to use PB Blaster and a wrench to get it to turn over then the engine was defiantly seized and not hydro-locked.
If no water came out of the spark plug holes it wasn't hydro-locked.
A hydro-locked engine will crank over as soon as you remove the sparkplugs, no lube or wrench is needed.

It really sounds like it seized and you broke it free with the lube and wrench. If this is the case you will have a catastrophic failure if you keep running it.

So what is the “fix”/suggested next steps?… she started last night and ran sweet as ever… I explained what happened to the Sea Doo dealer who suggested it happened more often than you’d think… their suggested approach is listed above… what do you suggest I do instead?

 

[mikidymac]

Check compression.

Yes, getting flooded and hydro-locked happens a lot.

Having to free the engine with lube and a wrench does not.

 

[LIBoater]

Check compression.

Yes, getting flooded and hydro-locked happens a lot.

Having to free the engine with lube and a wrench does not.

I checked compression... 130 PSI rear, 140 PSI front... and both held... I think I dodged a bullet!... according to the Sea Doo dealer, sometimes you "get away with it" and sometimes you don't... thanks for the advice!

 

[LIBoater]

Rain stopped play on the sea trial... will try tomorrow night

 

[mikidymac]

150 psi is perfect and at 120 it typically won't even start in the water.

More concerning would be the 10 psi difference.

If I was to suspect a bad cylinder it would be the 130 psi one. Good luck with your sea trial.

My fingers are crossed for you.

 

[LIBoater]

Hmmmmm despite the ski firing up on first crank when connected to the hose in the driveway and running fine (revs Climbed evenly as throttle increased), when I tried to start her when launched, she cranked a few times, almost caught, then locked and won’t start, so back to square one… have bought the ski home again and now contemplating a top end rebuild… have never attempted such a thing in the past, but I am quite handy… how simple is it and/or are there any other things I should try first? By the way, the shaft is locked again and I can’t turn it (even with vice grips), so I am suspecting the worst… would be interested to know what I should check for, based on the symptoms only recurring once launched? Thoughts?

 

[mikidymac]

Pull the jet pump first since you will need to to remove the engine. You might get lucky and it is just a seized jet pump.

 

[LIBoater]

Pull the jet pump first since you will need to to remove the engine. You might get lucky and it is just a seized jet pump.

What would cause the jet pump to seize between my driveway and the boat ramp?… I hope you’re right btw

 

[mikidymac]

It is unlikely but since it has to come out anyways it is worth checking.

Make sure you remove the stainless hat from the driveshaft carbon seal before removing the pump.