"diesel car".....Your coach uses the Centroid Fuel Sending unit. Here is a link to servicing it.
http://www.centroidproducts.com/moncal.htm
How to find the sending unit. On the driver's side, you should have a panel where the fuel door is located. On most Monaco's, that panel is hinged at the top, but is not setup to open. If you look under the edge of that fuel door panel, there will be two straps (again most Monaco's) with a screw in each. Remove the screws and lift the panel up, holding it up with a broom handle.
About 18" into the bay, you'll see the Centroid sending unit. It has several wires going to it. There are also adjustment screws. Over the ten years I owned my Monaco, the sending unit acted up 2-3 times. Each time I had an issue, I cleaned the wire connections and gave the adjustment screws a turn. This always got the unit working again. One of the adjustment screws adjusts your full tank setting.
I always had good look getting it to work again by doing the above, but I know a few that had to replace the sending unit. If you replace the unit, it includes the generator pickup tube. You may need to pay attention to that length. You don't want it to go all the way to the bottom for safety reasons.
CENTROID PRODUCTS
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Linear Mode
