2012 Mercury 40 HP 4 stroke- Water pressure at idle

[Reservoir Runner]

Just curious as to what the idle water pressure should be on this motor. It is putting out a good stream and the guage is showing almost 10 psi. I had the guage replaced about a 2 years ago cause it wasn't showing the correct pressure. The water pump has not been changed as I only have about 10 hours on the motor.

[Mike Cork]

10 PSI is pretty strong at idle. Most motors use 10-14 as a minimum at WOT.

[Reservoir Runner]

Ok, Thanks Mike!

[Princeton_Man]

Suggestion; if it's been more than a couple of years, go ahead and replace the water pump.