1969 JD 4020 Gages

[kurt.reynolds]

I have a 1969 4020, runs great, more of a hobby than a work tractor so to speak. None of the gages work. They bounce but never leave the low peg. Oil Pressure, Temperature and fuel gage. Not sure what those 3 lights are on the right side.

I guess I need to do some more research, but wondering if there are any tips on getting them working, or more specifically, can I just replace them all and start over.

Thanks
Kurt

 

[Jim.ME]

(quoted from post at 12:30:46 11/04/20) I have a 1969 4020, runs great, more of a hobby than a work tractor so to speak. None of the gages work. They bounce but never leave the low peg. Oil Pressure, Temperature and fuel gage. Not sure what those 3 lights are on the right side.

I guess I need to do some more research, but wondering if there are any tips on getting them working, or more specifically, can I just replace them all and start over.

Thanks
Kurt

I agree, you need to do more research. Looking at an Operator's manual, you don't have an oil pressure gauge, oil pressure is one of the indicator lights, you have a transmission oil temp gauge. Running around without the monitoring/warning equipment could cost you way more than manuals. 4020s have been around for years. You can take your serial number and find a number of used OEM John Deere Operator's and service manuals for it on eBay. You can even get a free download of the operator's manual at the John Deere Ag technical publications site. https://techpubs.deere.com/ The other manuals can be purchased there as well.

You could have no power, bad wires, bad gauges, bad senders, blown bulbs, or a combination of those things. Have you checked to see which if any gauges are mechanical, not electric (I believe at least the coolant temp is)? You need to locate the sender/probe end for each gauge. You need to see that the electric gauges and indicator lights have proper power to each. Wiring and connectors need to be checked between the gauge/light and its sender, wiring diagrams can help with that. Replacing gauges will do no good if the problem is in the wiring. Do you have and are you familiar with using a multimeter, as well as a test light?

 

[kurt.reynolds]

... Do you have and are you familiar with using a multimeter, as well as a test light?

I am familiar with multimeters and have one. I don't have a test light or continuity tester. Thanks for the thoughtful reply, I will start with the coolant temp and see what I can figure out.

-kurt

 

[Scott 730]

The 2 temp gauges are mechanical. The fuel gauge is electrical. Lights are for oil pressure, alternator, and air filter restriction. Do you have an operators manual? If not, why not?

 

[Scott 730]

And the aftermarket gauges are junk. They won't fit without modifying the holder clamps. BTDT.

 

[JD Dave]

The upside is that all of your gauges issues are repairable. With electrical gauges, - those that have only wires to them, require an electrical sender connection (usually a grounded connection)
and then test power to the gauge. The most common example is the fuel gauge. It's quite simple as are the diagnostics. Make sure you have power to the gauge terminal. Make sure to have a variable
resistance from the tank sending unit depending on the level of the float. Many old tractors will require a new sending unit because the old one is "crapped up" and dirty and won't send a reliable
signal/. Resistance measures vary over the years with the change from 6 volt to 12 volts. Read your manual and know what the specified battery is. Some early oil pressure gauges were "mechanical",
meaning that there was a physical, small line connection to the gauge. A lot of original gauges would "jump around" which was normal. Talk to Jerry at Evergreen Restorations. He's the king of gauge
issues supplier of the highest quality parts.

 

[SVcummins]

Any relation to burt

 

[Jery]

Try Evergreen Restoration. web www.evergreengauges.com

 

[6cylpower]

He will fix you up with quality gauges. Even has new indicator lights now.

I dropped the fuel gauge and added an oil pressure gauge on my 3020. The lights and AT24101 oil gauge were NOS.