saltwater in combustion chamber piston #3

[carlosbch]

A few weeks ago returning home from fishing engine started to sputter. Got home did all my regular wash down flush system and decided to check plugs . The #3 plug was fouled in a white crystal like chalk. i tasted and it was all salt. I replaced the two gaskets and its still the same. Is there another way that water can get into the chamber other than the gaskets?
Engine is a yamaha 225 2001 0x66 I'm so confused..

[boscoe99]

Cracked head for one.

[TownsendsFJR1300]

+1 ^^

A leak down test should help narrow it down.

Pulling the outer water jacket cover again(atop the head), pressurizing the cylinder (leak down test), and spraying some soapy water on the head (if the heads cracked), should bubble up big time. You'll hear it too..