Oil and water milkshake from sparkplug holes

I purchased a 1996 GTX and had tole address some basic electrical issues and replace some components. After ski did the double beep thing I go to turn over and she won't crank while the plugs are in. I took the plugs out today to see if it was a battery or drain issue.
As I was turning over the engine after removing the plugs, an oil and water milkshake spatter was spraying from the plug holes. It must be causing a hydro lock condition while the plugs are installed that keeps it from fullyta turning over.
My question is...
The Ski has been out of the water for some time and wasn't used this past season, so where is the water coming from?
Also, if it is oil injected, and wasn't used last season, why do I get milkshake when I turn it over now?
Could there be water in the exhaust system that is backing up into the cylinders and mixing with the oil that is getting injected while I am turning it over? Could the fuel be contaminated with water and while I am turning it over the milkshake and hydro lock is what is occurring?
I was going to check the fuel tank tommorow for contamination and clean and prime the fuel tank and lines up to the carburetors if that is the case, then continue to crank with out the sparkplugs installed to see if it clears out the milkshake.
Does anyone have any ideas as to the correct way to move forward, or if there could be more damage or cleaning out that would need to be addressed before I try to start it?
Any advice or suggestions would be appreciated as I am a noob and could use all the help I can get.


Active Member
No idea where water came from. Oil likely from leaking crank seals…rotary valve cavity. Milkshake and crank bearings NOT a good mix.
OK, that is a place to start, I will look further in that direction today to find the leak and cause of the water. I appreciate your help Toby. Thank you for your advise


Active Member
You never know what the previous owner did, they may have left it on the hose and turned motor off and got water in the cylinders (not suppose to do that). I would clean everything up, get that fluid out of the cylinders. Try to crank it after a thorough inspection. Get rid of that gas and I would replace the inline gas filter and possible the gas selector switch (could try and see if it works first). Get new plugs, make sure they are the right ones.
If you haven't already DL the repair manual and parts manual for your ski, free on the web. Go though them and read about you issues.

Post back and let us know how it is going.
OK, didn't accomplish as much as I wanted but I was using small amounts of gasoline to pour into the cylinders to clean and flush the milkshake out. Over the course of many sequences of pour small amount, crank engine, sprays out of plug holes, it finally started to clear up. The cylinder on the PTO side seems clean without any more oil or water, just gas. The other cylinder is taking longer to clear out. I just repeated the process over and over.
After I figured the one cylinder was clean, I tried installing only the one plug in that cylinder and expected that it should have at least gotten one full rotation if all the milkshake was cleared out. I had the same result of hanging up before one full rotation completes. By this time, my battery, and spare battery were worn down. Last thing I did was pack up the batteries for recharging and removed the starter and rear support mount.
My rear support is cracked so I will have it welded this week.I also purchased a used, but, OEM starter from a 96 gtx. I will install it upon arrival with the repaired support mount. It has the 8 tooth bendix for additional torque.
If the other cylinder doesn't clear out, or if the problem persists, should I remove the head for access to the actual pistons and cylinders?
Also I am a Machinist and fortunately have access to a fully equipped shop and inspection department. If I have to get intrusive with the removal of the head, would it be a good idea to remove the juggs, fully clean and inspect them, remove the old cylinder sleeves and press in new standard size ones, and re-ring after honing to size?
I figure if I'm in this deep, try to correct everything I can, without breaking the bank, and get the most improvement in reliability and safety as I can. With the installation of new gaskets during reassembly I will have effectively completed a top end rebuild for the most part.
The weather in my area is supposed to be crappy all week. Are there any suggestions as to investigative steps to try to see how serious the damage could already be, or how to find the cause of the water intrusion, or the oil intrusion. Are there any tell-tale signs to look for? Would removing the exhaust system and inspecting it for any leaks or existing water in the system be a good step to ruling out or confirming a possible mistake with water shut off while on the hose last?
I just feel as if the season is fast approaching and have no time to loose.
Thank you for the insight thus far provided, and the advice with my situation. I appreciate the guidance and hope to be able to do the same for someone in the future as I gain experience and education.


Staff member
Once you get the new starter in and fresh battery crank it with your thumb over one of the plug holes at a time. This will provide crankcase pressure and bring more of the junk up to the top of the pistons.


Milk means water intrusion. You must have a leaking gasket somewhere. I can only get my exhaust to seal to the header by coating the gasket with a sealer.


Staff member
Milk means water intrusion. You must have a leaking gasket somewhere. I can only get my exhaust to seal to the header by coating the gasket with a sealer.
Or someone flooded the engine by rolling the ski or flooding the hull, or having the flush hose on with the engine off. Both are more common than leaking gaskets, operator error is real, LOL.


Or someone flooded the engine by rolling the ski or flooding the hull, or having the flush hose on with the engine off. Both are more common than leaking gaskets, operator error is real, LOL.
Yeh, but he should know if he rolled the ski, ... Just saying, oil/gas+water=milk. If the source of the water is unknown, then its a gasket.


Staff member
Yeh, but he should know if he rolled the ski, ... Just saying, oil/gas+water=milk. If the source of the water is unknown, then its a gasket.
He bought it used. All bets are off with a used ski, LOL.
You could be correct but people sometimes do crazy things.

I bought a pair of 97' GSX's from a really nice guy that was tired of paying for storage. I went to look at them and noticed the drain plugs were in both skis. Said he hadn't been out with them in 5 years. When we pulled the seats they were full to the carbs with water just from rain.
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I tend to agree with mikidymac, maybe it was just flooded somehow. I am not sure but if the exhaust is full of water
it might prevent cranking ? I would make sure all water & bad oil is out, cylinders clear of milkshake, exhaust clear,
good oil, and try to start. If it does start I would check oil very very frequently.
Good afternoon everyone. Due to other responsibilities I haven't been able to get on the ski in a bit. However, I did recieve an original seadoo starter from a 96 gtx. I have heard that aftermarket are iffy and oem create more torque. Hopefully with a fresh battery and the oem starter it will reduce the timeframe required tommorow to finish any remaining flushing of the one cylinder, and the drawing of the new fuel from the tank(fresh fuel) through the lines to the carbs. I am anticipating at least a firing condition tommorow. I will then hook it to the hose, restart, then turn the water on.
I do have a couple questions though.
1. I figure it should smoke till any residual oil left in the cylinder burns off. How long should it smoke heavily to burn off the oil? I will try to use the observation of how long it smokes, and how it behaves as an indication of whether it is continuing to have water enter the system or if it is clearing up.
2. When I do run the ski to clear it out, and flushing in general, how long can I run it on a hose?
On my sterndrives, I flush for about 7 mins at low rpm. I read that jetskis are supposed to idle out of the water at 3000 rpm and I don't want to do any damage to what may be a bad situation making it into a catastrophic situation.
I greatly appreciate all the insights of the members here. The opinions and experiences of fellow members have been more helpful than I can say, and have been driving the way I am moving forward.
Sincerely, thank you for all the help. I will post the results as soon as I finish tommorow.


5 min per 2005 GTX op manual
Directions for Flushing, note that hi revs 4000-5000,
may just be to flush, may not be needed for what you are doing.
It says hi revs for 20 seconds, 5 min max, but does not specify
a min rpm. I am not sure but I would not think that 3000 is needed.

All Models

To flush the exhaust cooling system,
start the engine then immediately
open the water tap.
Certain components in the engine
compartment may be very hot.
Direct contact may result in skin
burn. Do not touch any electrical
parts or jet pump area when en-
gine is running.
CAUTION: Never flush a hot en-
gine. Always start the engine be-
fore opening the water tap. Open
water tap immediately after engine
is started to prevent overheating.
Run the engine about 20 seconds at a
fast idle between 4000 - 5000 RPM.
CAUTION: Never run engine with-
out supplying water to the exhaust
cooling system when watercraft is
out of water.
Ensure water flows out of jet pump
while flushing. Otherwise, refer to an
authorized Sea-Doo dealer for servic-
CAUTION: Never run engine
longer than 5 minutes. Drive line
seal has no cooling when watercraft
is out of water.
Close the water tap, then stop the en-
CAUTION: Always close the water
tap before stopping the engine


Also found this: so you need to clear intake manifold also.
Submerged Watercraft

To limit damages to the engine, per-
form the following procedure as soon
as possible.
Drain bilge.
If it was submerged in salt water,
spray bilge and all components with
fresh water using a garden hose to
stop the salt corroding effect.
CAUTION: Never try to crank or
start the engine. Water trapped in
intake manifold would flow towards
the engine and may cause severe
damage to the engine.
Bring the watercraft to be serviced by
an authorized Sea-Doo dealer as soon
as possible.
Installed the oem starter and was like night and day torque wise. She tried to start right up. Had a dog sitting home with her legs crossed, so I had to get home for her, and made an early evening of it. But happy with today's progress and excited with the results overall.
I will drain the old fuel and get fresh fuel up to the carbs. Swing by the marine shop and get a gallon of Seadoo oil, lube up all the control cables and put it in the water this weekend and let it idle. I really don't know what to expect once it is running, except an initial burning off of excess oil from the residual stuff left in the cylinders.
Can someone who has been following my situation give me some pointers about tell tail signs that may raise concern of additional serious issues?
If the smoking doesnt clear up and it continues to sound ok, what could that signify? I will shut it down immeadiately if the crank case starts to sound ugly. Is there a way to tell what may be an issue, say with the rave valves sticking? Is there a specific type of noise to look for that would point towards jet pump issues? or drive shaft ? Other than veiwing the oil flowing in the tube from the pump, is there a way to recognise an issue from the oil injection system? With the ski being as old as it is, i am worried how much repair work was attempted by someone who has like no experiance, or a solid clue about proper repair and maintenance like me. Any input about things to look out for, anything additional i am missing, some safeguards i can put in place ect. just to make it go smoothly on start up day, would be greatly appreciated. I would like to thank every member who was kind enough to take the time and comment on my questions and offer the insight of their experiance to assist a noob like myself who has only just joined the group. I hope to be able to assist someone in the future and pay it forward.
Good afternoon everyone,
Had a mixed day Wednesday, tried to start after changing out the fuel. Seemed like it wasn't getting any gas. I pulled the carbs yesterday and cleaned them today. Pretty messy in there. The fuel inlet bowl on the MAG side was full of sediment and crud. Spot rust and old fuel deposits throughout both carbs.
I cleaned both and I will reassemble with existing gaskets. If that fixes the starting issue, I will get a fresh rebuild kit for each on order. Next nice day here is Sunday so I will let the group know how it went.
Thanks again for all the advise and direction during this project.