Water coming out exhaust manifold (thermostatstuck open?)

[hyd-n-seek]

Hi, <br /><br />Yesterday, I noticed water sputtering out of the exhaust manifold on my 250hp OX66 right after I started the engine. It seemed to stop after I had run the boat for a short while. <br /><br />I'm guessing, based on what I've read in other posts about thermostats being stuck closed that I have the opposite problem -- mine is stuck open. Does this sound right? If so, <br /><br />-- what would I be looking for (debris, corrosion, etc.) as the cause of the problem?<br />-- is the process for removing the thermostats (I understand there are two on this engine) pretty straightforward? <br />-- Is it a mandatory gasket replacement if I remove them?<br />-- Do I also have to disassemble the pressure control valve assembly?<br /><br />Thanks in advance for your help.