Mercruiser water pressure sensor

It appears that my water pressure sensor is faulty, which I understand is a pretty common problem. I found an older thread on another forum discussing possible alternatives for the "OEM" sensor, which costs about $140, and New Eagle was mentioned as possibly being the sensor manufacturer. I was wondering has anyone been able to figure out how to order one and from where?

Alternatively, does anyone know how to successfully bypass this sensor? Again I found multiple discussions in older threads, but thus far I haven't been able to find the correct resistor value... If anyone can shed some light I would really appreciate it.

This sensor cause my engine to go into Guardian mode yesterday at the worst possible time (crossing a choppy inlet) and it wouldn't let me go above 1200RPM.... I really don't want this happening again, and if these sensors are known to flake out, I would much rather bypass the sensor altogether and rely on my temperature gauges (analog and VesselView).

P.S. Since you guys are probably going to ask, the engine is a 2005 Horizon MPI 350 Bravo, serial 0W3285##

Change the sensor with the OEM part. Check the plug and make sure it is not corroded. Most pressure sensors fail in range, when and if they fail. Accurate water pressure readings are a must.

Replacing the sensor with the "OEM" part is definitely an option, however I will try to source it directly from the manufacturer first, before I spend $140 for the same thing, but in a Quicksilver bag. More importantly, I would like to understand how frequently these actually fail? Based on what I have read on multiple forums, it appears that the failure rate is rather high, thus quite a few people carry a spare on-board. If that's truly the case then I would much rather prefer to bypass this sensor by using a resistor with the correct value to keep the ECM happy. I don't find the water pressure readings to be important whatsoever - all I need are the basics - temperature, oil pressure and RPM.

Good luck.

2004 350 MAG [FONT=&quot]#0W010098

I guess the water sensor is something I should consider replacing for 2020 as a maintenance item? Its a FW lake boat[/FONT][FONT=&quot] [/FONT][FONT=&quot]raw water system. Also where located on engine? The cost is not the issue when compared to everything. P/N? I'll guess I'll find it the Mercruiser [/FONT][FONT=&quot]IPB. Thanks
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sab said:

2004 350 MAG #0W010098

I guess the water sensor is something I should consider replacing for 2020 as a maintenance item? Its a FW lake boatraw water system. Also where located on engine? The cost is not the issue when compared to everything. P/N? I'll guess I'll find it the Mercruiser IPB. Thanks

Click to expand...

The revised part number is 8M6000623 and the sensor is located on the power steering cooler on the back of the motor. The earlier versions were white (at least mine is) and the new one is black.

Should the sensor fail, I have been told you can disconnect it and your engine will still be in Guardian mode, however the power output will only be limited by 10%. I haven't tested that personally, but I plan on doing so next time I go out.

Thanks will scope out the job when take the boat out of the water to winterize.

Thanks will scope out the job when take the boat out of the water to winterize.