1989 waverunner 500 water in cylinders

dan2744

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Waverunner keeps fouling out, when I I check plugs they are covered with water. Compresdion 130 on both cylinders. Where could could water could watered getting in?
 

dan2744

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How many places can water get in? Where would it most likely crack? Water jets were full of sand but I am not seeing a definitive crack, it may be a hair line crack somehere, i also had a questionable spot on the head gasket. Would a blown head gasket give a good compression reading because of water in the cylinder?
 

alldodge

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Water seals up cracks and increases compression. From what your saying, I would pull the head and see what you have
 

dan2744

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Pulled head, cylinders look better than any motor I have ever pulled a head off of. I am leaning towards a bad head gasket. I dont see any indication of anything, I am looking for some sort of exhaust leak that pulls water in cylinder on down stroke. Can that happen?
 

alldodge

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Your not going to suck water in from the exhaust with a 2-stroke. The read valves allow air and fuel mix to be drawn thru the intake, around the crankshaft (to lube crank) then up into the cylinder to burn. The burn gases are expelled when the cylinder starts back down.

Your water can be because the block has a crack. The pic below is a crude image and doesn't show the water jacket which surrounds it. So if the block is leaking water in the crankshaft area, the water gets sucked into the cylinder along with fuel and air.

Was the motor winterized?

2 stroke.jpg
 

dan2744

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Im not sure if it was winterized or not, I would guess no, I have it apart right now and cant find a crack, I will keep looking, its obviously internal if its there.
 

dan2744

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There was no thermostat, that does not make me happy. The water running through there was really cold, it may have flooded the engine during flushing.
 

dan2744

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I did the correct flushing sequence, will that let in to much water? I would imagine that the thermostat would restrict flow, maybe the pressure was to much?
 

alldodge

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I did the correct flushing sequence, will that let in to much water? I would imagine that the thermostat would restrict flow, maybe the pressure was to much?

If you started the motor, then turned on the water, and turned off the water before turning off the motor, I would say this should not have allowed water in. Now if you have some very high water pressure, it could let water in. A 2 cycle just as a 4 cycle, can be run for short periods without water (maybe 2 minutes)
 

dan2744

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Well, it starts, I am fouling plugs do to the 2 stroke oil bath that I gave the crank, its taking time getting the oil out, but, it is running. Is there a plug on these crank cases that I can unscrew to drain it? If not, I guess I will keep turning it over with plugs out and let it shoot it out the cylinders.
 

dan2744

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Here is a video of it running on a hose, it seems fine, I ran it for about 10 minutes like this. The black oily water that was coming from exhaust changed to nic e clear clean water now, no overheat, no wet plugs.
 

alldodge

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No drain that I know of, and it appears to be doing OK now. Maybe your out of the woods
 

dan2744

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I hope so, thanks for the help, I'm gonna try for a water test soon. Supposed to be 65 and sunny here in Michigan tomorrow. I cleaned out the water jackets very carefully with one of those tools you use to get nuts out of the shell.
 
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