water coming out sparkplug hole and in oil

[Nautique88]

I have a 88 nautique with original motor, the guy i bought it from said it was rebuilt but i dont know. The other day i pulled out my spark plugs and out the 3rd plug back on the passenger side water poured out. I took the distribute plug out and turned it over and more water is pumping out of it. I then took of the exhaust manifold and the riseres and they seem to be in pretty good shape not much rust at all. I then did a compression test on all the cylinders and the all read about 100, the one with the water is reading 120s. The oil in the boat was also milky so i drained that. Does any one know what this could be and were i should start to try and fix it? The motor does not over heat and runs great so i dont know what to do.

[Hydrofoilmaniac]

RE: water coming out sparkplug hole and in oil

Yikes, sounds like a bad head gasket.

[surroundsound64]

RE: water coming out sparkplug hole and in oil

Definitely a head gasket.

[richard]

water coming out sparkplug hole and in oil

if the manifold and riser near the end of life,worth to replace it before try other.

[Nautique88]

RE: water coming out sparkplug hole and in oil

Wouldnt the motor have been over heating if there was somthing wrong with the head or head gasket? the boat ran strong at 160. Im wondering if it could just be the exhaust manifold or riser because its weird that water is only in one cylinder. and it doesnt over heat at all or bog out it runs great.

[whataboat]

Probably the riser gasket is shot and leaking water back down inside the manifold when the engine is not running.
The oil was milky as some water would have seeped past the piston and into the sump, contaminating the oil.
If a head gasket was shot, water would be getting into the oil while the engine is running and the oil level would increase as you run the engine as it is being topped up by water

[Nautique88]

^ thats what the mechanic said, the oil didnt get milky untill after the boat was sitting for a while.