Replace a Bad Block Pressure Sensor mercruiser 350 MAG Boat Engine - 8M6000623

Part # 8M6000623
Make sure to Get Genuine Quicksilver - Mercruiser 8M6000623, 710-8M6000623
Don't get a Chinese Copy they don't work.
So while on my Monterey 340SY 2014 I was having some Weird Guardian Alerts Issues and one of the issues was a Bad Block Pressure Sensor on my mercruiser 350 MAG Engine. In this video I will show you how to figure out if yours is bad it's easier if you have a Dual engine like mine so you can compare your starboard engine vs your port engine and if one is way off then it's time for a new sensor. At first i got a Cheap Chinese replacement on Amazon but that still gave me issues so i purchased a Genuine Part and that fixed it once and for all.

[walterballantyne]

So the SmartCraft Gauges are actually missing a decimal, if it shows 65psi that is actually 6.5 psi and so on. I have the exact same setup and when reading it with a Scan Tool like the Rinda Techmate Pro you will see 6.5 while the gauge shows 65. Good info on the location and replacement though! Thank you for posting

[TeenagedSky]

Can this sensor be changed with the boat in the water?

[paprt]

Did that replacement take care of the fault code? After replacement was everything normal?

[ibrahimhoblos]

Hi would the location be the same on a 4.3mpi v6 mercruiser ? Thanks

[ScoutyBoyO]

I see the for sale sign. Are you buying a cat boat? LOL

[kylebernholz]

What was the fault code displayed when it went into guardian mode?

[lukefennell]

Dude the calibration of the sensor on the dial is wrong. You don't have anything like 71PSI raw water pressure when idling. It will be more like 15-20 at most. Get someone to check it for you.

[thomascarlsen]

I did the replacement, still having 2 beeps