Hunter 386 freshwater tank sending unit help

[BroncoJohn]

My freshwater and black holding tank level indicator is not working. I removed everything to access the freshwater sending unit and was surprised to only see 2 wires going into the middle side of the tank 7" apart. I was expecting a sending unit mounted from the top.
I will test the wires to measure the resistance but do I service this by drilling a new hole from the top and installing a vertical sending unit?

 

[Ralph Johnstone]

Pretty difficult to tell what level sensor you have as this is an after market installation. Always ensure you identify your equipment as these are boats, they're not cars. Each Hunter or Marlow Hunter boat coming off the assembly line will have differences, both small and large.

The attached manual is for a New Providence sensor which I installed on my holding tank. It will tell you everything you want to know about foil external level monitors. However it won't be exactly the same as yours as it's unlikely to be the same make.

 

[jssailem]

It could also be a SCAD sensor. They are a pair of copper foil strips that attach to the side of the tank. The wires do not go into the tank. They are taped to the side of the tank and send a signal of the conductance of the tank fluid back to the controller. Very good sensors.

TM™ Tank Monitors | Technologies LLC

www.scadtech.com

 

[flightlead404]

I replaced my wema gauge and sensors with the scan tech external ones. Happy

 

[BroncoJohn]

Great feedback!
They look like a great alternative without having to install float sensors.

 

[ice breaker]

Looks like the old snake river stuff. On our boat the foil had come unglued from the side of the tank in a few places. I repositioned them and then filled in behind them with expanding foam. They have work flawlessly for the last 13 seasons.

 

[BroncoJohn]

Would the white block that came unglued from the tank cause the sensor to malfunction?
Hopping I can get a Ohms reading empty to see if my problem is the sensor.

 

[Ralph Johnstone]

Would the white block that came unglued from the tank cause the sensor to malfunction?

No. Not unless wires have come disconnected in the junction box.

Are you going to tell us the make of the sensor and display, or is this on a NEED TO KNOW only basis ? How do you know your display unit senses resistance? Has your display unit worked in the past.

Did you ever hear the saying "help us to help you" ? You've offered no information on this sensor and readout so IMO you're on your own.

 

[BroncoJohn]

I believe everything is original to the boat. It is a 2002 Hunter 386 with less than 500 hours. I have had the boat for a bit over 4 months. Attaching a picture of the holding tank monitor.
Both my black water tank and fresh don't register on the monitor. I have tried filling the fresh water tank and resetting the monitor but it errors out or when it did take the reset it did not last for long as I remember.

 

[jssailem]

Have you inspected the wires and all the connections, cleaning and then reconnecting the connections?

 

[BroncoJohn]

I wanted to provide a final update.
I replaced the external tank sensors that with new ones and replaced the Snake River tank display with an iSeries Tank Systems Monitor. Everything seems to be working fine now.
the old sensors were serviceable but the aluminum foil strips were deteriorating and the copper sensors patch was oxidized.
Also the previous owner had purchased a new iSeries tank monitor display and I found it in a box of parts.
Apparently my whole problem was that the previous owner disconnected the diesel tank wires and ran a new gauge to the helm. I think monitor was reset by a battery change and it thought the fresh water was the disconnected diesel tank and my fresh water was reading my holding tank.
The iSeries monitor was easy to configure and I now have access to the tank levels.
I may add a secondary external sensor to the diesel tank later.

 

[Enrique Cortes]

Hello everyone, I'm trying to figure out what is going on with my tank monitor system, the one that is not working properly is the fuel one, sometimes mark a couple of lines sometimes full tank and now is just empty, i notice that the LED on the sender at the tank are not on, any ideas how to check this???? i really appreciate your help.

LED on the

 

[Ralph Johnstone]

Hi Enrique and welcome to the site. For the best response to your question, I would suggest you copy it and then paste it as a new enquiry. I would also suggest you indicate the year of your boat.

Your question becomes difficult in that unless someone with a similar year to your boat replies, we have no way of knowing who manufactured your fuel gauge as Hunter doesn't make fuel gauges, they only install them in boats as they manufacture them.

Do you have the boat's manual ?

 

[jssailem]

Hello Enrique. Welcome to the forum.

 

[ice breaker]

You will need a new sender. Check with WEMA. I believe that the ohms on the hunter system (snake river)are not standard, so make sure they understand that you have. I would also suggest that you pull it to make sure you order the right length. Mined died at year 6. I replaced it with a round WEMA gauge and new sender. All is good 14 years later.