Water tanks location

[Udi]

Hi. I own a Hunter 45DS model 2009/10. the boat have 3 water tanks.
I am experiencing some problems with the quantity display that isn't accurate, and I want to check the sensors.
I know the location of the forward tank which is located at the bow, and the location of other tank which is located under the floor near the sink at the galley.
The problem: I don't find the third one and how to reach it in order to take out the sensor for inspection.
I'll appreciate any help.
thank you.

 

[jssailem]

I am not a Hunter owner. I would expect that the water is located under the sole of the main cabin. The manual talks about 3 tanks. Here is the image with the locations found in the manual. If a previous owner modified the boat, they may have been moved or removed.

Source: https://sbo.sailboatowners.com/downloads/Hunter_45DS_980957.pdf

 

[Udi]

Hi. thank you very much. I am trying to find the sensor location of the forward tank (the one that near the aft) but I can't find it. maybe it needs a dismantling of the floor and not only simple opening a piol.
I'll check again this area.
thanks again.

 

[jssailem]

There are a couple of sensor styles. I do not know what was used on your boat or if a previous owner may have installed special.

One type is a float inside the tank. Wire are attached to the top of the sensor.

Another is a copper strip attached to the outside of a plastic tank.

What is the issue you are having with the sensors?

 

[Udi]

My type of sensor is the first one and its original.the issue is sensing the water height at the tank.

 

[jssailem]

If the sensor is functioning you can measure the electrical resistance with a digital voltage meter using the Ohm meter function. This link looks at a float sensor in a diesel tank. The float sensor in a water tank works the same way. As the float moves up & down electrical resistance is measured in the sensor. The wires between the sensor and the digital display pass that measurement to the display and you see it as level of liquid in tank.

Testing A Marine Fuel Sender - Marine How To

Empty - Arm Down = 240 Ohms The fuel sender, for the typical US standard used in a marine application, is a simple device that presents a resistance reading to the gauge with which it is paired. For US fuel gauges, from the

marinehowto.com

Testing the Ohm value will let you know if the sensor is working. If it is then inspecting the wires identifies if the signal is being transmitted.

The sensors sometimes fail and need replacement. Do the test to determine what is working and what is not.

Hope this helps.

 

[Udi]

Thank you very much for the info and suggestions.i'll try that and see. many thanks.