Hello to all, My BIL has a Ford 2000 Positive to Earth (Ground), his instrument cluster didn't work so purchased new one and both Temp & Fuel doesn't work. He has 12 volts going into the Stabilizer and 6 volts coming out. I know nothing about Positive ground systems. He has 6 volts going to new Temp sensor. Is all the above correct? Does both tractors Pos to Earth and Neg to earth take the same Instrument Cluster? What is the problem and how to correct? I'm tying to help him out he doesn't do internet. My other question is if the temp sensor already has 12 volts to the body since it's positive ground why would you have voltage also going to the terminal top of sensor? Thx
Ford 2000 3 cyl Gas Positive to Earth (Ground)
Vaughnd
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Hello to all, My BIL has a Ford 2000 Positive to Earth (Ground), his instrument cluster didn't work so purchased new one and both Temp & Fuel doesn't work. He has 12 volts going into the Stabilizer and 6 volts coming out. I know nothing about Positive ground systems. He has 6 volts going to new Temp sensor. Is all the above correct? Does both tractors Pos to Earth and Neg to earth take the same Instrument Cluster? What is the problem and how to correct? I'm tying to help him out he doesn't do internet. My other question is if the temp sensor already has 12 volts to the body since it's positive ground why would you have voltage also going to the terminal top of sensor? Thx
No it's 12 volts came from factory with 12 volt Positive Earth system, he's owned for over 25 years
No it came with 12 volt battery and no you can't hook up wrong, 12 V power into stablizer and 6 out to units one wire to each.
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As best as I recall the 6V systems were the only ones that came out as positive ground. When Ford switched to 12V everything was then negative ground including the 3 cylinder 2000 series tractors which is what I assume you are working since you mention the dash gauge voltage reg.
From everything I can find and info from including Tractordata.com the 3 cyl came 12 volt Neg ground. So why would his be 12 volt positive ground? Somewhere along the line someone would've had to convert it to this? He's had for 25 years and it's always been that way. If no one can answer that can you answer the temp? My other question is if the temp sensor already has 12 volts to the body since it's positive ground why would you have voltage also going to the terminal top of sensor? It had to work this way previously with old dash cluster.
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Maybe it was 6v positive ground and someone converted to 12v older machines aren't that hard to do . just need a voltage divider at the dash .
I'm making a guess that the dash between 6 and 12 would be different .
I'm making a guess that the dash between 6 and 12 would be different .
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I have no idea why anyone would have reversed the polarity other than they did it not realizing they did.
You would not. Looking at a wiring diagram voltage it is a simple circuit. The dash stabilizer is connected to one side of the battery, plus or minus depending on how the battery is connected, in this case the negative battery terminal since it currently positive ground. the other terminal of the staabilizer goes to one side the temp gauge, the other side of the temperature gauge goes to the terminal of the temperature sensor in the block completing the circuit.
So keeping it positive ground, a simple test would be to remove the battery wire from the dash stabilizer then use a jumper to connect to the negative side of the battery and see if it works.
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The only cars I worked on that were positive ground were 6 volt...and that was over 50 years ago...this thread got me thinking and I started doing some research on Positive ground and came across this video.....you might find it interesting and / or informative
I suggested that to him earlier today he just replied back and said he tried the jumper and gauges did nothing. This is 2nd cluster first one stablizer just passed 12 volts thru. Any other ideals?
Thx I watched that video already, I've searched everything on net and haven't found answer and seen all videos. Him and I are in different states. Think back a little harder now!
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The 3 cylinder 2000 was made from 1965 through 1975, so if he has only owned it for 25 years, it was owned by one or more previous owners for at least 23 years. It originally came from the factory with a 12 volt negative ground system. While it is possible to hook the battery up with a positive ground configuration and re-polarize the generator so that it also charges the battery when it is hooked up as positive ground, it was never recommended. Some previous owner could have rewired it to be positive ground at any point before he got it. One of the main reasons that car and tractor manufacturers switched form positive ground to negative ground back in the late 1960's through the mid 1960's was because a negative ground gives a hotter spark.
The voltage stabilizer is actually a temperature sensitive self resetting switch that switches on and off once every 1.5 to 2 seconds or so. A digital voltmeter will not be able to keep a steady number in the display from the constant switching on and off. An old fashioned analog voltmeter will show the average voltage, which should be between 6 and 7 volts.
Your "other" question:
The voltage stabilizer is actually a temperature sensitive self resetting switch that switches on and off once every 1.5 to 2 seconds or so. A digital voltmeter will not be able to keep a steady number in the display from the constant switching on and off. An old fashioned analog voltmeter will show the average voltage, which should be between 6 and 7 volts.
Your "other" question:
First off, in a positive ground system having the positive side of the battery going to something, or grounding something, does not provide "voltage" to it. It provides ground. The "voltage" is the -12 volts from the other side of the battery. Everything is always measured relative to ground in any system, whether it is positive ground or negative ground. The temp sender (sensor) is grounded through its body to the engine, but there should be a single wire going to it from the temp gauge, and that wire should come from the side of the gauge that is not connected to the voltage stabilizer on the back of the instrument cluster. If the gauge doesn't work wired like that, try reversing the two wires on the gauge, as it might require the current to flow in the proper direction to function properly, and since it is positive ground instead of the original negative ground, the current may be flowing in the wrong direction and the needle might be trying to go toward the colder side when it is already pinned there.
Since nothing has worked out and you sound like you know what is going on: What exactly does he need to do to convert it to 12 volt negative ground? Has generator. Would you explain please and I will pass on, i've searched online and got the basis. Is this the right path: He would totally discharge the battery and recharge back normally, On the Coil + primary terminal should go to the ignition switch and the - terminal should go to the points. Is this correct so far, what about the voltage regulator, starter, anything else, I don't want to inform him wrong and ruin something. Thx
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I know that other guys are going to want to try to help, but @Nouveau Redneck (aka Sean) is recognized as being extremely knowledgeable about the older Fords...I have tagged him, so he will get notified ... in order to avoid confusion and conflicting information, please let's wait for Sean to answer....not looking to put pressure on Sean, nor to discard any other help, but it is best way to get a straightforward way of going forward for OP
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I did not recommend reversing the input on the stabilizer, I suggested reversing the wires on the gauge. Big difference.
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No need to discharge the battery. The only thing that needs to be done is to reverse the battery cables, make sure that the coil is hooked up correctly and then polarize the generator. To polarize the generator, once the battery is connected as negative ground, pull the "field" wire from the Voltage regulator and momentarily touch it to the Batt terminal on the voltage regulator. Once you see a spark, it is re-polarized properly, and you can plug that wire back into the field terminal.You are done. You may still need to reorient things in the instrument cluster correctly and possibly replace any parts that are not working.
Which will not make any difference on a bi-metal gauge. The heater coil does not care which way the current flows.
Depending on how the ignition coil terminals are marked, it can be hard to determine which wire goes where. The pencil trick is easy to perform:
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