Water Pressure sensor

B

Bam073

New Member
Mar 1, 2008
177
Long Island
Thanks to GMAN in the general forum section I think after further research that I've found the problem. I'm getting two beeping sounds every few minutes.

Anyone have this problem? Any insight would be greatly appreciated.
 
had a problem with the low water pressure alarm a week ago...boat wouldn't overheat, but guardian kept shutting me down........tech replaces sensor, problem solved (except for $250 they charged me for parts and labor)
 
The part is #mm881879010 cost $90 takes less than 5 minutes to change with a 1" deep socket or open end wrench. Coulda saved yourself $150.
 
petern said:
had a problem with the low water pressure alarm a week ago...boat wouldn't overheat, but guardian kept shutting me down........tech replaces sensor, problem solved (except for $250 they charged me for parts and labor)
Click to expand...

That's the difference, I wasn't being shut down. The boat operated as it normally does. I know my marina is going to come back and say it was faulty and something stupid that triggered the alarm. Then reality sets in and says nope, you'll be billed at least $300 for this something stupid that I think it is!
 
daddyox said:
What does the actual sensor look like? How do you find it? Your engine different than mine?
Click to expand...

About 1-1/2" long with a 1/8" npt and a 3 wire harness connected at the top. It's located top left rear of the engine on the power steering cooler and is easily visible.
 
You'll need a long socket (sorry forgot the exact size), extension bars and possibly a flex socket adapter. You will need to lay on the engine so remove the cover, arrestor and anything else that looks like it may break when yo are on the engine. A mover's blanket folded over several times is a good way to safely lay on the engine in comfort. The sensor should come out rather easily. Might have to warm up the engine a bit if it does not. Be sure to remove the electronic connector first (It can only go in one way).

New sensor will come with red thread sealant on it - if not, you'll need to add some of the red stuff to the thread, just a drop. Might get some water come-out of the opening but not enough to keep you from screwing in the new sensor. Do this by hand if possible or you may ruin the threading!

... And lastly, this is where the little bugger is if you were looking at the back of the engine...
 

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i figured that out when I saw the dead one the tech left behind........lesson learned.....also, flflatrate says he can get them for $60. I need to chat with this shop....I need them to be there for me over time, but I don't need to fund his entire retirement in one season..........
 
Great forum! I googled water pressure sensor and 350MAG and searched for hours with no avail...I joined Club Sea Ray and found help in minutes.

I have the same 2 beeps and a message that the water pressure sensor is faulty. gerryb's picture was great it confirmed where I thought the sensor was. I will tray and clean it or replace it soon.

Thanks all!
 
Removed the sensor and found a few grains of sand. Rinsed with water and blotted dry. Replaced it and ran the engine 3 times for about 5-10mins. No more beaping and error message. I'll take it for a spin tomorrow. It may be a coincidence, or maybe the sand was clogging the hole to the sensor.

Either way, it really does only take 5mins to replace. A 1" deep socket is the only tool needed.

Thanks again
 
I've posted regarding faulty water pressure sensors several times. Because of the frequent replacement issue I have also had, I'm planning to keep my old sensors, and the next time the new one goes I plan to put a little solvent (methyl hydrate) down the sensor hole and blast some high pressure air into the sensor. Maybe, just maybe they can be cleaned. They are easy to replace once you know how, but at $60-$150 bucks each and $150/min one hour labour, depending on who you ask, it's not that cheap when it's happening a few times a year. I also read here on a forum that it could be due to running in shallow water which admittedly I do quite frequently in the Cayman Islands-we anchor just off shore quite a bit and it's a sandy bottom. Hope this info helps.

sundeck 260
 
What would happen if I don't replace it, as long as I monitor and have constant temperature between the 2 engines?
 
WatPres2.jpg
http://i107.photobucket.com/albums/m305/SeaRay300/WatPres2.jpg

The part# is 881879010, and it lists for $107.50.

The range is 0-50 PSI.

Make sure they don't confuse it with the oil pressure sending switch, who's part # is 881879011, one digit different.
The list on it is $109.17, and the range is 0-100 PSI.

Don't ask me how I know this...
 
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Just sent you back a pm. Price is $100 Shipped to the U.S. Don't have them at the price I had on here a few years ago.
 
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