115trld water pressure drop

[saltydog]

Have a 2005 Yamaha 115trld w/carbs. I am certain water pump is going out. Tattle tale water pressure lower than normal & gauge shows about 12-15 psi drop from normal. Before I change out water pump, where does the tube coming from the (Yamaha Water Pressure Gauge) connect to the engine? Just trying to cover bases before repairs. No overheating or alarms.

[mitch]

could also be your pressure relief valve stuck open