Water in cylinders 99 250 OX66

[jf123]

I am picking up water in cylinder #3 and #4. I plan on pulling the exhaust plate but notice on the scematics that the 250 does not use an inner divider. Does the 250 use a dividing plate and it is just not listed or some other means ? Cylinder heads were already removed and inspected. Any other suggestions on where to look for water intrusion? intake side?

[boats.net]

No it doesn't have an inner plate but pull cover and look for corrosion or holes.