2000 U320: Up until now the fuel gauge has been working OK. Not totally linear but definitely reflected the fuel level. Gauge was at 1/4 and we added fuel (125 Gal) and it came up to 3/4. Probably should have read a little higher after adding 125 Gal (out of the 192 gal fuel tank size). Drove about 20 miles and parked for 3 nights and then left a friend's hill top home on a steep and windy road. When I next looked at the gauge it was pegged above full. gauge did not budge from then on and I knew the fuel level was below the filler neck. Drove another 150 miles and gauge still above "F". Visually checked the level and it is 3-4 inches below the filler neck. Drove another 200 miles and now it is moving SLIGHTLY when cornering on exit ramp.
Thinking it was stuck in full position, and thinking it was a float type sender, I thought my driving on the windy steep driveway may have got it stuck in the full position. So I was going to fill the tank as full as possible and see if that unstuck the float. After reading the forum I learned that it is not a float type but a capacitive dual tube detector. Since the gauge is moving when cornering I have decided to just let the level go down lower and see if the gauge "waked up. Using a "Silverleaf" to track level by tracking fuel usage based on the cummins data.
Does anyone have any idea what might have caused this to suddenly off the track and what I might do to get it back on track. I guess there is a calibration procedure that was described by Beamalarm Barry. What I read referred to water levels. Not sure that is the same for fuel. Will read again, and this time before I have my cocktail.
If it is similiar to mine you can get to the wire terminals from the passenger side of the fuel tank,check for loose/corroeded wires.
Howdy Tom,
I would second John44 suggestion. Its possible to remove a small access cover that's around the passenger side fuel fill fitting, and you can see the connections. I've attached a couple of photos from when I had fuel lines replaced. These photos show the fuel sender.
Good Luck, Dave A
I have had sender issues a few times with my coach. I have tapped the sender unit lightly with a hammer handle or a wrench. Seemed to read more accurately afterwords.
I went to Centroids web site and found it to be very informative. I've worked with Instrumentation for more than 30 years and really like this design. The newer programmable units have a feature that will show WATER CONTAMINATION IN YOUR TANK! It will show as an over high level indication on your gauge. They suggest monitoring the filling and if it goes high while filling then you are pumping water in your tank. It could be that you have a puddle of water that is moving along the bottom of your tank.
If yours is the older style with the calibration pots, after checking the terminations, I suggest marking where the current calibration of the Full Pot position is and then repeatedly rotating back and forth 180 deg (or stop to stop) to clean the wiper. Return it leaving it slightly off (10 deg) from your previously marked position. Check the Fuel gauge, it should be close enough. COVER THE POTS with electrical or suitable tape to help seal out moisture and dirt. I don't have this unit but basing it on the calibration procedure and experience.
Fortravel sells a replacement sending unit.. $170 ish I believe.. its auto calc. works great and fixed my adjustment issues.