low water pressure

[retiredhans]

I have a 1999 90hp C90tlrx outboard that developed low water pressure in recent years and also starts to run hotter when running over half throttle.
I have replaced the water pump kit several times which did not correct the problem.Thermostat and pressure valve have also been replaced.The tell-tale-hole shows good discharge.On a recent flush with "Ear-muffs" I noticed a discharge of cold water from the front of the lower casing where it bolts to the middle case near the speedo nipple.I am wondering if that coult be related to my problem

[boats.net]

May have bad powerhead gasket, pull powerhead and inspect gasket and water tube grommet.