Inconsistent water pressure on 2014 250 ProXS

[Tidewater Bass]

Guys,

I have a 2014, 250 Pro XS (2B113454) with inconsistent water pressure. When starting at the ramp I'll have 3.5 - 4.0 psi at idle and engine cold. Engine temps climbs to 120-124 and stabilizes. I make a run and water PSI is between 16-22 psi at 5000 rpm with temps in the mid 80s. Once the throttle is brought back I've been letting her idle for a minute or so and notice my water pressure is now at .8 - 1.5 range? (The thermostats, water pump, and poppet valve were renewed apx 10 hours ago a the 100 hour mark by Mercury dealer. This as done as a preventive maintenance item not due to cooling issues.) Once the engine cools the PSI improves (thermostats should have closed). I haven't yet but do plan on pulling the thermostats to see I they have any sand, wood or other "stuff" in them. Am I missing anything here? Anyone else see these same symptoms? What did you do to correct?

[Tidewater Bass]

Sorry forgot to say water PSI as displayed on Smartcraft.

[Fishysam]

My analog gauge acts like your saying, but when I come off plane idle for a few seconds in gear then feather the pedal back I for a second I get full pressure 4-5 again. I feel like there may be air in the LU that gets removed by the feathering. Try that next time your out

[Fishysam]

Don ?

[willymac]

I can watch my water pressure and temp on merc monitor and see when the tstats open and close. I'm not sure where the pressure reading comes from in the cooling system, but it would make sense for the pressure reading to drop with the tstats open if the pressure sensor is upstream of tstats.

[Fishysam]

T-stats open does make some sense to me since I had one get stuck open and I only had .5-1psi water pressure. Still hoping to hear more.

[Tidewater Bass]

This afternoon I removed both thermostats and found wood in the port/left bank valve that was not allowing it to close. I was surprised at how much and what size material was stuck in the valve. I also cleaned the compressor strainer but didn't find much there. I hope to get her underway this weekend to see what the water pressure looks like now.

[Tidewater Bass]

Ran the boat today and all seems fine.