Don, 400 Verado water pressure alarm

[32regulator]

Ok, brand new 400r with sportmaster LU. went to lake for testing today. Boat jumps on plane , but once on pad won't go above 4500rpms. Then you start to feel her lose power (RPM) and soon after water pressure alarm goes off. Neither water pressure on merc monitor or analog gauge move.....stay at 0.9 psi. Think they moved to 1.4psi, but again just stayed there. Then received SVS check engine alarm. Water pressure looks good streaming from engine. Some sort of sensor bad possibly???

[iron banks]

32, I have the 350 verado on my Jaguar. When it was new I had an intermittent over heat alarm. Brought it to dealer and they went through everything. Turned out to be a loose engine harness. They unplugged it and plugged it back in and it has worked flawlessly ever since. Check that and make sure it is making a good connection because that will play hell with the electronics making it appear to be other issues.

[EuropeanAM]

Please see the Forum Announcements, and be sure to provide the REQUIRED info when posting. Thanks!

For this instance, don't rely on the telltale.

Need to verify the actual pressure available to the Block Pressure Sensor (with a known-accurate analog gauge). Could be a sensor problem- or could actually be low pressure.

If this is a brand-new engine, your nearest Verado-Qualified Mercury Dealer is equipped to address this concern.