[RussWhite]

Forest,

No it is not swing arm. It is an enclosed aluminum tube. Inisde there are two tiny wires and a float that slides up and down the wires connecting them together as it slides. When at the top the wires are effectively shorted and the resistance is near zero. When at the bottom ( your tank is empty ) the wires have almost their entire resistance since they are now connected at the bottom and the gauge should read empty.

It is a VERY difficult job due to the location of the sender. Moving the tank or removing the door makes it easier, but either of those jobs are difficult themselves. I just couldn't stand mine not working at all. Knowing what I went though, I would probably just live with the situation you seem to have.
If you get into it I have lots of pictures of how I did it.

[Chester Stone]

Russ, I am posting my recent experience to maybe help someone in the future. First, I easily removed the old sending unit by using the jack and wood as shown in your photo. The old sending unit was broken between the head and the tube. I installed the new sending unit (VDO 224-270) easily with just the jack and wood, and the top metal bar quickly returned to its original shape without bending and I did not have to file down the head of the unit. Secondly, the new sender does not work. I researched on the internet and found that the old sending unit was a VDO 224-004 which they no longer make. The dash gauge and old sending unit are 10-180 ohms, whereas the new one is 90-0 ohms. Thirdly, simple solution: I ordered a new dash gauge (VDO 301-905) which is 90-0 ohms for only $31. The lesson here is to be sure the gauge and sender are compatible. Keeping my fingers crossed that everything works with the new gauge.

[RussWhite]

Chester,

I will keep mine crossed as well. I think, if it works, that changing the gauge was the right decision at that point.

It sounds to me like your tank may have been slightly more toward the outside of the coach than mine was. Post back when you get the gauge installed. Russ