JD 3020 Diesel

[Clint Barnhart]

I have a 3020 JD Diesel. I replaced the fuel sending unit and the fuel gauge reads full no matter how much fuel is in the tank. The fuel gauge is new. Any ideas on what I can do fix this?
 

[jddave]

You say your gauge is new. Is it a John Deere part or another replacement item? Some John Deere gauges replace the original and do not appear original nor do they wire the same requiring a work-around to ground a terminal plus hot wire and sender wire. Make sure the polarity is correct also. You can check the gauge by grounding the sender terminal. With and without ground and the gauge should read alternately "full" and "empty". Then check the resistance of the sending unit from "full' to "empty" with a multimeter set to OHMS. There should be a range of roughly 20-60 ohms I think. Any questions ask Jerry at Evergreen Restorations advertised in Two-Cylinder. Of course another issue is a short in the sender wiring which would ground the signal but this is not common. The sender housing must be grounded to the tank and tractor. Check for complete ground with a multimeter. I always bench test the fuel gauge with the sender before installing them.
 

[tim s]

Yes, you "must" be sure you have the proper gauge to match the system, tell me is it 12 or 24 volt, console or not..and I"ll give you the correct part numbers...
 

[LonM]

I would add to make sure you have the correct sender for your year of 3020, as the early vs side consoles had different ohm specs in the senders. Ours always read full too and I fought that for a long time before I double checked the part number! Good Luck, LonM