Battery cable size Farmall H

[Grandpa's 8N]

What size was the negative battery cable on a 41 H from the factory. Both off of the battery and the one going to the starter.

 

[old]

Big as your thumb as in 0 or 00. 6 volt systems need big cables due to the fact they work on low volts but very high amps. Oh and by the way that holds true for both + and - cables

 

[El Toro]

00 as Old recommends and be sure to clean all surfaces until shiny including where your battery is grounded. Hal

 

[rustyfarmall]

(quoted from post at 19:24:22 07/29/12) What size was the negative battery cable on a 41 H from the factory. Both off of the battery and the one going to the starter.

Original battery cables were #2 gauge. Most replacements are #1 gauge. #0 or #00 is overkill and not necessary.

 

[John T]

Bottom line and basic engineering FACT the bigger the cable the less voltage drops and less I Squared R Heat loss. Since you only have 6 volts to start with and a heavy starting current draw might reduce that to as low as 4.5 YOU CANT AFFORD TO DROP MUCH VOLTAGE AND HAVE HEAT LOSSES IN THE CABLES, you need all the energy possible discharged in the starter NOT the cables.

So sure, heck a 1 or even 2 gauge cable will work and the starter will turn, but if she needs to start in cold temps, I in good engineering faith and conscience have to advise you use at least a 0 gauge better yet 00.

Your tractor your money your choice, bigger cable (best if not so big it can still fit the termination devices and ends of course) will allow for better cranking however

John T

 

[rustyfarmall]

(quoted from post at 07:24:46 07/30/12) Bottom line and basic engineering FACT the bigger the cable the less voltage drops and less I Squared R Heat loss. Since you only have 6 volts to start with and a heavy starting current draw might reduce that to as low as 4.5 YOU CANT AFFORD TO DROP MUCH VOLTAGE AND HAVE HEAT LOSSES IN THE CABLES, you need all the energy possible discharged in the starter NOT the cables.

So sure, heck a 1 or even 2 gauge cable will work and the starter will turn, but if she needs to start in cold temps, I in good engineering faith and conscience have to advise you use at least a 0 gauge better yet 00.

Your tractor your money your choice, bigger cable (best if not so big it can still fit the termination devices and ends of course) will allow for better cranking however

John T

John, I have 2 Farmall Hs. Both of them are the original 6 volt systems. Both of them have #1 gauge battery cables. Both of them crank over easily and start well even at temperatures down to 0°. The battery cables on a Farmall H are not all that long, and a #1 gauge cable will easily get the job done.

 

[John T]

Good info especially for H fans, original is what I "usually" like to use, except for battery cables on 6 volt tractors, where bigger ones drop less voltage and theres less heat loss, but as long as she starts in cold weather and is ORIGINAL, hey thats what many choose and Im sure not one to argue against an owners choice, I'm NOT any "Correct Police" kinda guy lol................

John T

 

[JMOR]

(quoted from post at 10:21:14 07/31/12)

(quoted from post at 07:24:46 07/30/12) Bottom line and basic engineering FACT the bigger the cable the less voltage drops and less I Squared R Heat loss. Since you only have 6 volts to start with and a heavy starting current draw might reduce that to as low as 4.5 YOU CANT AFFORD TO DROP MUCH VOLTAGE AND HAVE HEAT LOSSES IN THE CABLES, you need all the energy possible discharged in the starter NOT the cables.

So sure, heck a 1 or even 2 gauge cable will work and the starter will turn, but if she needs to start in cold temps, I in good engineering faith and conscience have to advise you use at least a 0 gauge better yet 00.

Your tractor your money your choice, bigger cable (best if not so big it can still fit the termination devices and ends of course) will allow for better cranking however

John T

John, I have 2 Farmall Hs. Both of them are the original 6 volt systems. Both of them have #1 gauge battery cables. Both of them crank over easily and start well even at temperatures down to 0°. The battery cables on a Farmall H are not all that long, and a #1 gauge cable will easily get the job done.

hen it comes to many things, such as guns, hammers, wire, your prize 'tool' and the like, bigger is better, BUT.....it is hard to hold the position that 28 one-thousandths of a volt (0.028v) out of 6v or stated as a percentage, 0.47%, will make or break a start. Based on 150amps cranking current (from a tractor manual spec sheet) and estimated 4 feet of #1 vs 00 gauge cable. Diminishing returns comes to mind. How small can you get the bolted connections? Be your own judge.

 

[rustyfarmall]

(quoted from post at 00:34:36 08/02/12)

(quoted from post at 10:21:14 07/31/12)

(quoted from post at 07:24:46 07/30/12) Bottom line and basic engineering FACT the bigger the cable the less voltage drops and less I Squared R Heat loss. Since you only have 6 volts to start with and a heavy starting current draw might reduce that to as low as 4.5 YOU CANT AFFORD TO DROP MUCH VOLTAGE AND HAVE HEAT LOSSES IN THE CABLES, you need all the energy possible discharged in the starter NOT the cables.

So sure, heck a 1 or even 2 gauge cable will work and the starter will turn, but if she needs to start in cold temps, I in good engineering faith and conscience have to advise you use at least a 0 gauge better yet 00.

Your tractor your money your choice, bigger cable (best if not so big it can still fit the termination devices and ends of course) will allow for better cranking however

John T

John, I have 2 Farmall Hs. Both of them are the original 6 volt systems. Both of them have #1 gauge battery cables. Both of them crank over easily and start well even at temperatures down to 0°. The battery cables on a Farmall H are not all that long, and a #1 gauge cable will easily get the job done.

hen it comes to many things, such as guns, hammers, wire, your prize 'tool' and the like, bigger is better, BUT.....it is hard to hold the position that 28 one-thousandths of a volt (0.028v) out of 6v or stated as a percentage, 0.47%, will make or break a start. Based on 150amps cranking current (from a tractor manual spec sheet) and estimated 4 feet of #1 vs 00 gauge cable. Diminishing returns comes to mind. How small can you get the bolted connections? Be your own judge.

Exactly my point! The LONGEST battery cable on a Farmall H is just right at 3 feet in length.

 

[John T]

EXACTLY,,,,,,, I agree. Theres less voltage drop and less I Squared R heat loss in a bigger cable, Ohms Law still applies and thats indeed an inescapable engineering fact. HOWEVER, as starter current increases over ideal conditions (engine problems or starter problems or common and typical connection problems or colder temps etc) then voltage drop becomes much more and more critical. PROBLEM IS if you go wayyyyyyy too big then the connectors and terminations and attachments become troublesome.

If a tractor starts fine in cold temps with X size stock cable (Like Rustys) no need to go bigger but if there are problems due to excess voltage drop, then as you stated, bigger is better (subject to limitations above). Im NOT one of the Correct Police who pick and judge other peoples work so if people like pure stock Im happy but if they choose to go with improvements its their tractor and their money and their choice and NOT ours so I dont come down on people who use stock ORRRRRRR who use improved products

Thanks gang, fun chat for us sparkies and hope we helped and didnt bore the others lol

Best wishes n God Bless yall

John T