Water Pressure Sensor Alarm

Sep 8, 2018
43
Boat Info
240 Sundeck 2006
Engines
5.0 Mercruiser w/Bravo III Drives
Just wanted to thank people on this forum. First time out on my new to me 2006 240 Sundeck the water pressure sensor alarm went off, I checked the digital reading and the water psi was fine, a quick search on my cell led me to posts on here where it seems it is a common issue. Back home I researched the site some more and ordered a replacement part along with a 1" deep socket. Took 5 minutes to fit the new part on the boat and since then no more alarm. Thanks for the info!
20180925_113535.jpg
20180925_113558.jpg
20180925_113607.jpg
20180925_113637.jpg
20180925_113641.jpg
20180925_113644.jpg
 
Curios how much you paid for that? Mine is starting to act up. Did you buy it from a dealer$$$
 
I keep a spare on my boat now. I believe they are right around 100$, no need to buy at dealership. Just search for your specific part/engine and get it online. Although, if you are in a pinch, some/most dealerships will have them in stock for same day purchase.
 
What was the psi when it was alarming and what is it now ? Got to love that price
 
What was the psi when it was alarming and what is it now ? Got to love that price

It was reading 0.0 psi when alarming, last time out I think it was running at about 3 psi (I may be wrong) but I will check when I'm out on it this weekend. Engine temp, oil pressure etc all run as normal. I will probably buy another one as a spare to keep on the boat in case it happens again.
 
It was reading 0.0 psi when alarming, last time out I think it was running at about 3 psi (I may be wrong) but I will check when I'm out on it this weekend. Engine temp, oil pressure etc all run as normal. I will probably buy another one as a spare to keep on the boat in case it happens again.

Just wondering if this part from Amazon is still working for you. My boat is doing the exact same thing, and I think I am going to give your solution a try. Also, on the photo where your camera is zoomed out showing the entire engine, it's tough for me to tell where to look for this part. Generally speaking, is it left side, right side, front, back, etc.? I could probably locate it quickly once I get to the dock, but just trying to be prepared for what to be looking for.
 
It is still working for me, never had a problem since (thankfully). The part is located in the middle section (approx) of the back of the engine. It was easy to replace and I have no mechanical knowledge to speak of. You really do need a 1" deep socket set and some kind of blanket to put over the engine as you will more or less be lying on top of it.
 
It is still working for me, never had a problem since (thankfully). The part is located in the middle section (approx) of the back of the engine. It was easy to replace and I have no mechanical knowledge to speak of. You really do need a 1" deep socket set and some kind of blanket to put over the engine as you will more or less be lying on top of it.
Excellent! I ordered the part on Amazon and will report back on whether I have the same success as you.
 
Excellent! I ordered the part on Amazon and will report back on whether I have the same success as you.
I am having a similar problem water psi is reading 0.0 but engine is cooling.
Engine cutting out at 2300 rpm.
I will try this sensor replacement.
 
I am having a similar problem water psi is reading 0.0 but engine is cooling.
Engine cutting out at 2300 rpm.
I will try this sensor replacement.
If your water psi is reading 0 then you may want to look at replacing the water pressure sensor. Just had mine done at the marina as it was reading 0 and now everything is back to normal. I believe the part is approx. $164 give or take. I didn't replace mine, the mechanic did, so I can't tell you how easy or difficult it is to do. I'm sure there will be a YouTube video on it though!
 
I tried the Chinese knockoff from Amazon it still read 0.0.
I bought the original from a mercury dealer and it fixed the problem.
Pressure read 2.3 immediately on idle and went up as I picked up speed.
No more knockoffs for me
 
Just want to say thanks for the info - I changed this sensor in less than 10 minutes. Would be great to have a 1" deep well socket but the box end on my combination works. Sensor on my 5.0L is just to the left behind the distributor. This link shows an OEM part (claims to be Merc) for $16 with free shipping. It works on my boat and we'll see for how long, but I won't be spending big $$ on this sensor and plan to order a spare. Oh yeah, you have to remove a 1/8" pipe thread adapter which adds about 50 seconds ;)

https://www.discountstarterandalternator.com/p/new-oem-pressure-sensor-mercury-marine-881879/

And damn its nice not hearing the buzzer every minute or so.
 
I’ve just had an alarm for 0psi with good water output on my STB engine after having replaced the sensor last year with a cheap Chinese one. I see Mercury have since upgraded the design of the sensor and it is up & running beautifully again. Lesson learned buy cheap get trouble! Never again will I buy anything other than OEM
 

Attachments

  • IMG_0029.png
    IMG_0029.png
    1.7 MB · Views: 32

Forum statistics

Threads
112,948
Messages
1,422,806
Members
60,930
Latest member
Ebrown69
Back
Top