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FUEL TANK SIGHT GAUGE
Author Last Post
Richard

Thanks.

Van
Joyful Noise
Selene 54

 

Douglas Van Nostrand, MD, FACP, FACNM

Director, Nuclear Medicine Research

MedStar Research Institute and Washington Hospital Center

Professor of Medicine, Georgetown University School of Medicine

Suite GA60F

110 Irving Street, N.W.

Washington, D. C. 20010

Office:  202-877-0300

Office Fax:  202-877-6601

Cell:  443-765-8300 (new)

Home: 443-817-2307

Home fax:  443-817-2308

Hospital e-mail:  douglas.van.nostrand@medstar.net

Private g-mail:  douglasvannostrand@gmail.com

 

 

 



Thank you Richard!


Where is that "beating the dead horse" emoji?


I believe the attached photo is how the sight gauges should look. It's pretty obvious where the fuel level is. But, sometimes the magnets get confused and don't look as organized as this. That's what the magnet is for. I run the magnet down the square sightglass to set the flippers to white. Then I use the magnet to attract the float magnet on the large cylindrical secion and drag the float down slowly and release it. It will slowly float back up and turn the flippers from white to magenta (or every 10th one, green).


Richard

Rob - yes, you can certainly toggle the flippers directly, just suggesting that moving the internal float to do such would be more informative.


And yes, quite a find - the shipwright helping us work through the boat had seen this problem before! I suspect it was actually that the tube itself had been mounted upside down. Too much work to fix all of that, so the simple fix was to just flip the internal float assemblies over. If our port and stbd tube had been switched at installation, they would have been inverted (vertically) and the thus in the correct orientation for the internal floats to work properly.


And, yes, in the attached photo you are seeing the tank senders strapped to the sides of the tubes because they weren't installed in the tanks while it was still possible. These were removed as soon as we had pressure-driven duecers affixed to the tank drains.


Carl

Ellipsis

2007 Selene 5906

Hi Carl -


that is too weird that a float went into your boat upside down. that's quite a find to figure out and correct!


i have not opened up our float tube but our little kitchen magnet will flip flippers at all points on the sight gauge, so i expect we're rotating the flippers directly and not dragging the float downwards through the diesel.


i also suspect that our float has two magnets in it, one at the top to show the level and another at the bottom to reset flippers as the float rises. it's interesting to me that three upper flippers are all aiming at a common point, and the three flippers below are all pointing at a different common point.


there's no reason to believe that the boats all have the same sight gauge designs.


rob

Roadrunner

2007 Selene 49 deep hull 48-029

We had to disassemble our magnetic “sight” gauges in 2007 to address issues with the chicklets (flippers) failing to operate as expected. We found that the inner magnetic float was actually an assembly with a float, a stem, and a small sinker weight at the end of the stem. This float assembly had been installed upside down causing the it to get “hung up” inside the tube. After correcting this oversight the flippers have worked reliably with the occasional single flipper or two inverted from time to time. Easily corrected with a strong external handheld magnet. Corrections are made by using the external magnet to “grab” the magnetic float inside the tube to drag it up or down inside the tube. This indirectly resets the flippers and ensures the inner float assembly is unencumbered. The external magnet should not be directly driving the flippers.


Carl Gulledge

MV Ellipsis s5906

Rob:

Thanks for the information
;Joyful Noise
Selene 54, 2012 deep hull.

 

Douglas Van Nostrand, MD, FACP, FACNM

Director, Nuclear Medicine Research

MedStar Research Institute and Washington Hospital Center

Professor of Medicine, Georgetown University School of Medicine

Suite GA60F

110 Irving Street, N.W.

Washington, D. C. 20010

Office:  202-877-0300

Office Fax:  202-877-6601

Cell:  443-765-8300 (new)

Home: 443-817-2307

Home fax:  443-817-2308

Hospital e-mail:  douglas.van.nostrand@medstar.net

Private g-mail:  douglasvannostrand@gmail.com

 

 

 



Joe and LInda

Good idea.  I did something similar.

Thanks

Doug
Selene 54
Joyful Noise

 

Douglas Van Nostrand, MD, FACP, FACNM

Director, Nuclear Medicine Research

MedStar Research Institute and Washington Hospital Center

Professor of Medicine, Georgetown University School of Medicine

Suite GA60F

110 Irving Street, N.W.

Washington, D. C. 20010

Office:  202-877-0300

Office Fax:  202-877-6601

Cell:  443-765-8300 (new)

Home: 443-817-2307

Home fax:  443-817-2308

Hospital e-mail:  douglas.van.nostrand@medstar.net

Private g-mail:  douglasvannostrand@gmail.com

 

 

 



Thanks for that Rob. I always figured the level was right in the middle. My assumption was the magnet is floating so the magnetic field would have equal pull up and down. Either way, its less than a 10 gallon difference on our 55. In April, I ran one tank to empty with the polisher and filled marking every 50 gallons and transfer that scale to the other tank and marked that one too. That worked out really well on our last fill last month.



Joe and Linda

401 Play

2009 Selene 55078

On Roadrunner the sight gauge flippers are dark above/below the fuel float magnet, with white flippers showing the fuel level. When I read up on the gauges, apparently the fuel level is read at the uppermost horizontal white flipper (the red arrow in the picture shows the reading point). So far we haven't gone wrong doing it that way. Somebody please chime in if the sight gauges are read differently.


The magnet can flip the flippers to different colors depending on which way the magnet is run up/down. My understanding is the gauge is supposed to return flippers to background color as the float magnet moves slowly up and down the tube. If the magnet is run quickly then the flippers don't always have time to respond to the magnet, and when that happens we get all-white. That's when we get out our external magnet and flip them back to background color.


rob

Roadrunner

2007 Selene 49 deep hull 48-029

I'll give it a try later today or tomorrow.

Thanks

Van

 

Douglas Van Nostrand, MD, FACP, FACNM

Director, Nuclear Medicine Research

MedStar Research Institute and Washington Hospital Center

Professor of Medicine, Georgetown University School of Medicine

Suite GA60F

110 Irving Street, N.W.

Washington, D. C. 20010

Office:  202-877-0300

Office Fax:  202-877-6601

Cell:  443-765-8300 (new)

Home: 443-817-2307

Home fax:  443-817-2308

Hospital e-mail:  douglas.van.nostrand@medstar.net

Private g-mail:  douglasvannostrand@gmail.com

 

 

 



When you turn them white with the magnet below the fuel level (I run the magnet from top down to reset), they will turn to red onto the fuel level after you remove the magnet.

Brad

Again, thanks for the information regarding the external vertical fuel level gauges.  


I obtained a magnet, and yes, it turns the little shingles inside the glass tube from magenta to white and back.    

But I noticed that I go one way and it turns all of them white, and I go the other way and it turns most of them magenta and a few white.   

So, how do I set it up and know that I said it up correctly to show what the level is of the fuel with the magenta-white interface showing the level of the diesel?

I appreciate any and all help.

 

Van

 

Douglas Van Nostrand, MD, FACP, FACNM

Director, Nuclear Medicine Research

MedStar Research Institute and Washington Hospital Center

Professor of Medicine, Georgetown University School of Medicine

Suite GA60F

110 Irving Street, N.W.

Washington, D. C. 20010

Office:  202-877-0300

Office Fax:  202-877-6601

Cell:  443-765-8300 (new)

Home: 443-817-2307

Home fax:  443-817-2308

Hospital e-mail:  douglas.van.nostrand@medstar.net

Private g-mail:  douglasvannostrand@gmail.com

 

 

 



Brad:

Thanks

Van


 

Douglas Van Nostrand, MD, FACP, FACNM

Director, Nuclear Medicine Research

MedStar Research Institute and Washington Hospital Center

Professor of Medicine, Georgetown University School of Medicine

Suite GA60F

110 Irving Street, N.W.

Washington, D. C. 20010

Office:  202-877-0300

Office Fax:  202-877-6601

Cell:  443-765-8300 (new)

Home: 443-817-2307

Home fax:  443-817-2308

Hospital e-mail:  douglas.van.nostrand@medstar.net

Private g-mail:  douglasvannostrand@gmail.com

 

 

 



The white is the air part on top. Think of it as without color/without fuel. The magenta is the fuel, think of this as red dye diesel. The green are simply reference marks. On my 550 gallon tanks, each green mark is roughly 50 gallons.


Brad Budinger

55-70

Moonstone

The white color is empty and the magenta/green is full. So the transition from magenta to white is the fuel level.

Mark


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Rob
RoadRunner

Thanks for the information on the magnet and the fuel tank gauge.  Pardon my stupidity or senior moment, I am not sure what colors mean what.  Of course, I have two tanks.  I have a magenta color with green every five steps, and I also have white.   What means what?   I  can take  the magnet and change them from magenta to white or white to magenta.   What should be showing how high the diesel in the tank is and what color should be above that .

I appreciate any help in making sure I understand this.    

Van

Selene 54

Joyful Noise

Magothy River

Douglas Van Nostrand, MD, FACP, FACNM

Director, Nuclear Medicine Research

MedStar Research Institute and Washington Hospital Center

Professor of Medicine, Georgetown University School of Medicine

Suite GA60F

110 Irving Street, N.W.

Washington, D. C. 20010

Office:  202-877-0300

Office Fax:  202-877-6601

Cell:  443-765-8300 (new)

Home: 443-817-2307

Home fax:  443-817-2308

Hospital e-mail:  douglas.van.nostrand@medstar.net

Private g-mail:  douglasvannostrand@gmail.com

 

 

 



Rob
RoadRunner

Thanks for the information on the magnet and the fuel tank gauge.  Pardon my stupidity or senior moment, I am not sure what colors mean what.  Of course, I have two tanks.  I have a magenta color with green every five steps, and I also have white.   What means what?   I  can take  the magnet and change them from magenta to white or white to magenta.   What should be showing how high the diesel in the tank is and what color should be above that .

I appreciate any help in making sure I understand this.    

Van

Selene 54

Joyful Noise

Magothy River

Douglas Van Nostrand, MD, FACP, FACNM

Director, Nuclear Medicine Research

MedStar Research Institute and Washington Hospital Center

Professor of Medicine, Georgetown University School of Medicine

Suite GA60F

110 Irving Street, N.W.

Washington, D. C. 20010

Office:  202-877-0300

Office Fax:  202-877-6601

Cell:  443-765-8300 (new)

Home: 443-817-2307

Home fax:  443-817-2308

Hospital e-mail:  douglas.van.nostrand@medstar.net

Private g-mail:  douglasvannostrand@gmail.com

 

 

 



Dear Rob & Mark,


Thank you so much as the magnet worked perfectly!!!


~Lucky

That behavior means the starboard float traveled all the way to the top of the sight gauge (above the top of the tank, in our case), unless the sight gauge has broken somehow. Inside the tube is a float with a magnet, making them simple with few moving parts.


The flippers can get stuck and not rotate back to dark as the magnet goes by. As Mark points out, running a refrigerator magnet along the flippers will flip them back.


- rob

Roadrunner

2007 Selene 49 deep hull 48-029

You can flip to black or white with a magnet. Can not say why they did what they did.

Mark
Freedom
53026

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