Exhaust in water

[hossn1]

I have been going through a 1990 dt 75 that i bought used. I pulled the thermostat out to check it and decided to start motor with the housing off to see if i had a good water flow. I noticed that I am getting an exhaust or compression coming out of smaller hole where the water goes thru head when thermostat opens. Is this normal? I have 140 psi compression in all cylinders so I beleive head and gaskets are O.K. Any help would be appreciated.

[boats.net]

Check the inner exhaust plate on side of engine block for holes in it.