Question for pos/neg ground

[Bodfarmer in ID]

Hey I have a 400 Farmall gas I picked up and was looking at the battery and noticed it was hooked up positive ground. It had a 12 volt battery. Does anyone know if that is correct. Any information would be greatly appreciated! Thank you.

 

[Bob M]

PROBABLY correct. 12 volt negative ground did not become common until the late 1950's and "industry standard" in the early 60's, when alternators replaced generators.

 

[Janicholson]

Hey I have a 400 Farmall gas I picked up and was looking at the battery and noticed it was hooked up positive ground. It had a 12 volt battery. Does anyone know if that is correct. Any information would be greatly appreciated! Thank you.

Probably had a replacement generator from that era that was setup correctly for 12v pos ground. IH didn't change to 12v in gasoline tractors until the X50 series, and not at the beginning of that. Farmall had 12v systems with Positive ground in MD tractors in the 40s. Jim

 

[used red MN]

How long you had the tractor? Does the generator, if so equipped work, showing a charge on the ammeter? How about the lights, do they work? (Just FYI if the bulbs are still 6 volt you will more or less immediately burn them out when you put 12 volts to them.) Just to start the tractor a good 12 volt battery will operate it easily for several days without charge unless you use the lights. Is there a resistor block installed by the coil? All I am saying is if it is a recent purchase, the previous owner could have just stuck a 12 volt battery in it and sold it to you all the rest of the system may just be the original 6 volt stuff.

 

[504]

Check the wiring at the coil.if the wire from the distributor is on the Pos side of the coil,it is wired for POS ground.(the distributor is the ground )and most people do not switch it when they rewire it. IH built them both ways 12V POS ground and 12V NEG ground.

 

[AJB-450]

Probably had a replacement generator from that era that was setup correctly for 12v pos ground. IH didn't change to 12v in gasoline tractors until the X50 series, and not at the beginning of that. Farmall had 12v systems with Positive ground in MD tractors in the 40s. Jim

My 400 that my dad bought used in 1965 is also 12-volt positive ground with a 12-volt generator. I believe a lot of 400s got converted to 12-volts with generators before alternators became common. And yes, my MD and 650-D also came from the factory with 12-volt generators and positive ground. Al

 

[Duner Wi]

My info says 400 could be 6 volt positive or12 volt positive. No mention of any Neg ground for 400.
My350 U is 12 volt positive since new. Give me the generator number. I might be able to tell you more.

 

[Bodfarmer in ID]

Thank you for your replys ,will check it out closer and get back to you .

 

[JIM MN]

Charging systems; 12 volts with a generator is positive ground. System 12 volts with alternator is negative ground.. Same with a 6 volt system...

 

[rustred]

Hey I have a 400 Farmall gas I picked up and was looking at the battery and noticed it was hooked up positive ground. It had a 12 volt battery. Does anyone know if that is correct. Any information would be greatly appreciated! Thank you.

it should be 6 volt pos ground. the 6 volt in mine spins the engine like 12 volts with the key. so if you have a 12 volt battery in it , it should be turning like an airplane ready for take off. you can tell that alone without even hunting around for starter numbers ,.. listen to how the starter engages also if it slams in its 6 volt. i have seen lots of these old tractor where the younger ones have no idea that things were 6 volt at one time and they just stick in a 12 volt battery. they just dont know so yes it can be a mistake.

 

[John Deere D]

Hey I have a 400 Farmall gas I picked up and was looking at the battery and noticed it was hooked up positive ground. It had a 12 volt battery. Does anyone know if that is correct. Any information would be greatly appreciated! Thank you.

READ what Rustred and used red MN have entered. Also,Previous Owner Syndrome is often a problem.