John Deere 4520 Batteries

[johnmor]

I recently aquired a 4520 and it has 2 6v batteries in series. I need to replace the batteries and am considering purchasing two 12V batteriesand wiring them in paralled. Does anyoner have any experience with this?

 

[wore out]

I recently aquired a 4520 and it has 2 6v batteries in series. I need to replace the batteries and am considering purchasing two 12V batteriesand wiring them in paralled. Does anyoner have any experience with this?

There's no reason you can't.

A single 1000CCA Group 31 battery would probably work just fine without all the need for cable to parallel two batteries.

 

[Bob Bancroft]

I recently aquired a 4520 and it has 2 6v batteries in series. I need to replace the batteries and am considering purchasing two 12V batteriesand wiring them in paralled. Does anyoner have any experience with this?

Not on this particular tractor. I agree with going with 12V batteries. A good way to wire them is independently. That is- run a positive cable from each battery to the starter solenoid, and a negative cable from each battery to near the starter.

 

[used red MN]

Should work fine. I’m not sure why some guys think that large castings bolted together tightly with at least 6 bolts that are at least 1/2 inch or bigger won’t conduct current as well as a battery cable. To each their own I guess. It’s all in how good the connection of the cable is to the casting.

 

[Texasmark]

I had a JD 4010 diesel that I welded a box on the side of the frame adjacent to the starter and put a 900 CCA 12v battery in that place and it worked fine.

Years later I acquired a cosmetically restored, beautiful professional job, full cab redo, 1979 4230 diesel with Sound Guard cab (with 3900 actual mowing hours) that had the series 6v setup (size 27 batteries) with 0 gauge wires connecting the batteries, one on each side of the tractor, using the engine frame as a current path for the return to the starter and the left battery was wired to the starter solenoid +....just an electric disaster for a high current application....400 cu in, 100 HP diesel.

I never liked to use "Ether" and over time the batteries needed replacing. I replaced each 27 sized 6 volt with a 31 sized, 900+ CCA (27 dimensions with 3/8" studs.....batteries that OTR truckers use.....batteries were real cheap as they bought the same battery on the skid and had hundreds of the same battery in stock for their OTR customers).

I ran parallel 00 gauge wires (that they made for me) from the right side under the floor pan, to a second identical battery, on the left, wiring them in parallel....rather than the resistance of the circuits being in series and adding up, impeding starting current delivery, they were in parallel, halving the resistance.

I then ran a short 00 wire (overkill but the tech was working with 00 so I said to make them all 00) to the starter frame under a mounting screw and another to the solenoid input, both being less than 18".

I didn't have to touch the key when I wanted to start it.......I just had the mental command and it started right up, regardless of the N. Tx. weather.....not quite, but you get the idea..........

I sold that tractor with a lot of other equipment when I downsized after retiring and no longer leased a lot of adjacent land. That was one fine tractor and my neighbor got many years of hard use out of it.

 

[4520BW]

There's no reason you can't.

A single 1000CCA Group 31 battery would probably work just fine without all the need for cable to parallel two batteries.

I added a battery box to mine and run a group 31 truck battery. I'll try to get a pic.

 

[johnmor]

I added a battery box to mine and run a group 31 truck battery. I'll try to get a pic.

Thanks! I would like to see it

 

[4520BW]

Thanks! I would like to see it

 

[4520BW]

Thanks! I would like to see it

Did same on 4020

 

[John T]

John, if you wire two identical 12 Volt batteries in parallel you have Twice as many cold cranking amps a d Twice as many Amp Hours of energy storage capacity at 12 volts. When starting a diesel at cold temps twice the CCA and twice the stored energy can improve starting and could yield faster cranking. Sure 1/2 the CCA could get you started fine but if it’s extremely cold I strongly advise two 12;s in parallel. Also quality bigger cables yields less line voltage drop and I advise that. If it were a gas engine only one battery has a better chance. Your tractor your budget your choice but twice the CCA and twice the energy is my advice.

PS if you used two 6;s in series while the voltage adds to 12, the CCA or Amp Hours of energy storage does NOT add so you ONLY have the cranking Amps one of those batteries can supply. Of course that still works as could a single 12, whatever your needs and works for you is YOUR choice

John T

 

[SkipperII]

One of the tractors I work on is a 4620. It had a single 12 volt battery(which he replaced with a new one) when my buddy got it. On cool days, if it didn't fire immediately, it had to be jumped. We installed the second 12 volt in parallel, and it fires right off now.

 

[BarnyardEngineering]

I recently aquired a 4520 and it has 2 6v batteries in series. I need to replace the batteries and am considering purchasing two 12V batteriesand wiring them in paralled. Does anyoner have any experience with this?

Your main gain will be from the cabling and fresh batteries, assuming you run all new cables and do separate "home runs" from each battery to the starter as mentioned above.

Replacing the "3EH" 6V batteries with "3ET" 12V batteries, CCA will be similar.

Per Interstate's website a 3EH has 850CCA. Two in series is 850CCA total.
Per Interstate's website a 3ET has 460CCA. Two in parallel is 920CCA total.

Really, not enough of a difference to be noticeable, all else being equal.

 

[BarnyardEngineering]

One of the tractors I work on is a 4620. It had a single 12 volt battery(which he replaced with a new one) when my buddy got it. On cool days, if it didn't fire immediately, it had to be jumped. We installed the second 12 volt in parallel, and it fires right off now.

What group battery, though?

A good quality Group 31 has around 1000CCA, slightly better than the factory setup.

 

[John T]

One of the tractors I work on is a 4620. It had a single 12 volt battery(which he replaced with a new one) when my buddy got it. On cool days, if it didn't fire immediately, it had to be jumped. We installed the second 12 volt in parallel, and it fires right off now.

EXACTLY because two 12's in parallel DOUBLED the Cold Cranking Amps. While a single or the original two sixes in series can perform okay, simply increasing the CCA and energy storage capacity can improve starting performance ESPECIALLY when its cold and needed the most. Its the OP choice subject to HIS budget and IFFFFFFFFFF he needs added CCA ??????????? Its NOT rocket science the MORE Cranking Amps and bigger battery cables improves cranking and starting ESPECIALLY when its colddddddddddddddd lol

John T