Fuel Gauge

[Ralph Johnstone]

I'd assume that any manufacturer worth their salt would add some resistance to dampen motion.

It's for a boat (maybe 1,000 units) and not an 80's or 90's car (one zillion units). Also, I don't think any car would ever see the up & down and swing & sway of a boat.

I know, pretty loosey goosey logic but as @Rich Stidger says :

I have had repeated failures with the type of sender that uses an arm with a float.

I'd tend to take a cautionary note from that.

 

[jssailem]

Stress not about the units "dampen motion" design. These units have worked for years. Do they work well? They can lack accuracy. How many times are you checking the fuel with the boat rocking?

If it is not working check the ground wire.

You can check the unit to see the ohm readings. Match them to the gauge and you’ll be good to go.
https://www.ford-trucks.com/forums/attachment.php?attachmentid=256613&stc=1&d=1516768438

 

[flightlead404]

Use an external stick on sensor with a plastic tank.

 

[PJL]

On my Passage 42 the gauge would never go below half full. Removed the sending unit and found that the float had crossed over the top of something. After moving the float all has been well...

 

[artboas]

Stress not about the units "dampen motion" design. These units have worked for years. Do they work well? They can lack accuracy. How many times are you checking the fuel with the boat rocking?

If it is not working check the ground wire.

You can check the unit to see the ohm readings. Match them to the gauge and you’ll be good to go.
https://www.ford-trucks.com/forums/attachment.php?attachmentid=256613&stc=1&d=1516768438View attachment 211840

The unreliability of the arm type sensors is that they use a resistive potentiometer which has wear, and is open to corrisiin
The tube type uses sealed reed switches.
So, unless your magnet fails (which is exactly what happened to me), these are a lot more reliable.

 

[jssailem]

I have a new sealed read switch designed sensor in my Starboard Tank.

Like you I wanted "reliability". In my Port Tank I have an arm type resistive potentiometer sensor from the early 70's that I did not change. I cleaned up the contacts, and assured the aged wires were fully functional. I tested the potentiometer and the ohm readings were spot on. I reinstalled it in 2015 and it is still fully functional. Not bad for a 50 year old piece of boat gear.

The new modern read sensor relies on the switches to function, the magnets to trigger the switches, and the float to move without obstruction or clogging. I like that it worked upon the 2015 install and continues to function.

Both sensors have failure points. It is wise to know them and address them should they occur.