Jump starting 6 volt H with 12 volt battery

What is the proper way of jumpstarting 6volt H with 12volts to keep from arcing or burning someting out. Where is it best to put the 12volts in between battery & starter? Thank you.

Connect neg and pos jumpers to neg and pos terminals on the 12 V. Then connect the neg jumper to neg post, then pos jumper to the point where the 6V pos is bolted to the frame (assuming that its still original pos ground) and hit the starter. As soon as its running disconnect opposite the way you connected. (My $0.02 worth. jal-SD)

Its dangerous to jump a 6 volt battery with a 12 volt battery, theres high current and the 6 volt can outgas explosive gas out its top and cause an explosion. If I wanted to jump start a 6 volt tractor using a 12 volt battery, I WOULD APPLY THE 12 VOLTS TO THE STARTER MOTOR ONLY such as one jumper lead to the frame ground and the other direct to the starter post or the starter side of a switch or solenoid. Id atatch the first clamp to the starter post (or starter side of switch or solenoid) and then jump the other lead to the iron frame near the starter. THIS WILL START THE TRACTOR IFFFFFFFFF the ignition is on and theres at lEast enough charge in the 6 volt battery to power up the ignition (none needed if its a Magneto).

DO NOT use jumper cables to apply 12 volts to a 6 volt battery especialy right at the battery top where sparking and explosive gasses may be present.......

DOOOOOOOOO match the battery polarities i.e. + to + and - to -........

If youre jumping a Pos ground tractor using a Neg ground vehicle dont let the tractor and vehicle be in physical contact

NOTE this can be a high current jump so use caution and make the last connection on the tractor steel frame no where near the battery


John T

While jumping a 6 volt tractor from a 12 volt vehicle is not recommended (there's a risk of the both 6 volt and 12 volt battery exploding if done improperly) it can be done.

Several precautions:

1 - Wear safety glasses, and keep bystanders well back.

2 - Shut down the 12 volt tractor engine before making any jumper cable connections. Leave it shut down while cranking the 6 volt tractor.

3 - Now proceed as follows:

Make all the jumper cable connections EXCEPT the frame (ground) connection at the 6 volt tractor.

Next, with the 6 volt tractor throttle set at slow idle, hit its starter and make the final jumper cable connection at the same time (expect an arc when you make the connection!)

The instant engine fires, release the starter button and IMMEDIATELY disconnect the ground jumper cable. Do this to prevent the 6 volt tractor's voltage regulator cutout from closing with 12 volts present in the system, possibly burning the VR's contacts.

Ever hear tell of battery explosion stories? They are true and a 12V boost on 6V is one of the classic causes.

I did that with a combine once, jumping 12 to 6 volts, and blew the top off one cell on the 6 volt battery. Fortunately I was not hurt but it was a loud explosion.

NEVER EVER hook a 12 volt battery to a 6 volt battery, if you do it could well be the last thing you ever see. Yes they blow up and most of the time when they do the person gets it right in the eyes. If you are going to jump start one you hook one jump lead to the frame of the tractor and the other one to the post on the starter. That way the 6 volt battery never has 12 volts on it but the starter does. This will not work if the 6 volt battery is flat dead so the 6 volt battery has to have enough in it to make spark or the tractor has to have a mag

Having read all the replies Steve I reckon it would be safer to go out and buy a new 6v battery.

Just like what everyone has said, never mix 6 volt with 12 volt. On the rare occasions my battery goes flat, I put a trickle charger on. If I absolutely need the tractor I will boost it by removing the battery leads and hook my power pack to the terminal ends. Once the tractor is running I reinstall the leads.

There isnat any PROPER way to do that unless you want an explosion. Why dont you just pull it to start then you cam,ove it near a chatger. Take a hydrometer reading you mite need a new battery or take it to a dealerwho can test it.

(quoted from post at 04:27:41 11/05/10) There isnat any PROPER way to do that unless you want an explosion. Why dont you just pull it to start then you cam,ove it near a chatger. Take a hydrometer reading you mite need a new battery or take it to a dealerwho can test it.

Click to expand...

Bull puckey, gene.

Your run of the mill charger/booster will apply well over 12V to a 6V battery in "10A fast charge" mode, and it's perfectly fine to leave it that way for hours.

A couple minutes attached to a 12V battery does no harm and puts you in no danger.

POS to POS
NEG to NEG
Pull the switch.
Push the button.

That's all there is to it.

Please follow John T's reply & forget the rest.

All of this info blows my mind. For the last 2 years I've been jumping my 6v tractor with a 12v battery charger and have never had an issue. Guess I should just go ahead and replace my battery so I don't have to jump it.

Butttttttttttt weedhopper, a 12 volt charger (depends on its size) DOES NOT HAVE THE CAPACITY to supply something like 500 amps or more (depends on battery size) like a 12 volt battery could, plus a charger has some degree of safety overcurrent protection unlike a big brute of a battery. Ive used a 12 v charger to charge a 6 volt battery but used the low charge settings and dont leave it unattended for long periods n keep an eye on the battery so shes not over cookign or over boiling or excessive outgassing etc THATS NOT AS DANGEROUS AS A 12 VOLT BATTERY JUMP (several hundred amps capacity) ON A 6 VOLT BATTERY but still Id make the last connection on the frame away from the top of battery

John T

I think you are right about the higher voltage. Even a generator or alternator puts out higher voltage.

The difference between a 10 amp charger and an 810 amp battery is about 800 amps of power. Enough to increase the size of the spark when attaching leads to a battery.

Of course the battery has to be outgassing when the spark occurs to get an explosion. I don't know when the maximum and minimums that a battery outgasses. I presume the 6 volt battery is at a low charge and the 12 volt has a full charge. The 12 volt with a running engine would have 13.6 volts going to it and maybe cause some outgassing. Opening the hood and quickly attaching leads would not let the gas dissipate and make things worse. Guess I'll see what others say about this. My 2 cents.

What your doing yes you may get by with but one of these days it also may blow up in your face. When a battery is over charged it produces a lot of hydrogen gas and that gas in turn is very explosive and one of these days you may just find out how big a bang it will make. I hope for your sake it does not happen because I know more then one person who now reads with there finger tips because of a battery blowing up and them loosing there eyes to the acid.Your play Russian roulette with doing that

What old said. And hydrogen gas is lighter than air. It rises and dispels in the wind. With a battery in the open, not much of a problem. A battery under the hood or in a battery box is a different story. The air & hydrogen mix just needs a spark.

They used to use hydrogen gas in the Zephlens (sp) and we all know what happened to one of them.

I will agree with John T 100 percent and only add that a lot of the tractors we talk about on here like and H or M farmall the starter terminal is easy to access and 12 volting them is a pretty simple matter. When you get to the Farmall C and even a super H or M where they mounted the switch on top of the starter you are entering a whole different situation at that is the battery hot wire. Don't run 12 volts to that unless you unhook the cable from starter switch and then you will have to connect the accessory wire to battery cable to supply current to ign. Magnetic switch type like on 300 or 400 series tractors you can hook directly to starter, just stay away from the battery cable side and do not turn key to start position.

BEEN THERE DONE THAT. NEVER AGAIN!
I jumped an old Chev 1 ton that had the 6v under the driver floorboard. Blew the top off the 6v battery and the arc started the floor matting on fire.

ONE EXCEPTION. IF THE 6V TRACTOR HAS MAGNETO IGNITION.
Then you can jump the 12v directly to the 6v starter to start it without damaging charging system. I did this all the time with an '41 H.

You may be right . I do not have 6 volt charger or battery but have checked voltage on 12 volt charger lots of times and got 15 volts maximum. MY trucks have 100 amp+ altenators and charge 14 volts maximum and 15.5 volts would put them in Red danger area on guage.

Use common sense, hook to the starter,start the tractor, unhook quickley. Lost a lot of respect for some peoplr over this post. We"ve all been doing this for 40+ years and those of us who think ahead a little bit still have 20/20 vision. Think about POLARITY never hook up a neg ground system to a pos ground system by hooking pos to pos and neg to neg always hook ground to ground and hot to hot. Always shut off 12 volt main jumping source or be good friends with the guy at the alternator/generator shop.

(quoted from post at 20:10:18 11/05/10) Think about POLARITY never hook up a neg ground system to a pos ground system by hooking pos to pos and neg to neg always hook ground to ground and hot to hot.

Click to expand...

It this advice where the expression dead wrong comes from? That could be the result.

NO! as Jim Becker says you are dead wrong about polarity. Positive to positive and negative to negative is common knowledge.

Youre doin better then me, Ive been hooking them up 50 + years BUT DO NOT HAVE 20/20 VISION (dern bi focals lol)

I dont want anyone to get hurt so with all due respect would like to comment on your statement just in case some here may be "corn" fused..I'm sure you know what youre talking about, I'm just worried some here may be confused by the wording of your posting........

Your post.

"Think about POLARITY never hook up a neg ground system to a pos ground system by hooking pos to pos and neg to neg always hook ground to ground and hot to hot"

My comments.

1) When hooking up a battery charger to a tractor or one battery to another, THE CORRECT "POLARITY" (with respect to the + and - BATTERY posts) IS ALWAYS POS TO POS AND NEG TO NEG.....REGARDLESS WHICH BATTERY POST HAPPENS TO BE ATATCHED TO SOME HUGE HUNK OF OLD RUSTY IRON.

2) Its a fairly common practice to use a Neg grounded truck etc. to jump start a Pos grounded tractor (done that 50 + years although lost my 20/20 grrrr). And the No 1 rule above MUST STILL BE ADHERED TO. Pos to Pos and Neg to Neg (relative to battery posts) REGARDLESS which battery post on EITHER vehicle is attached to the huge hunk of iron.

3) THEREFORE lets say the tractor is Pos ground while the truck is Neg ground (the majority of old tractors being jumped from your trusty pickup), how do you hook it up ????? ANSWER::::: POS TO POS AND NEG TO NEG.

4) All one has to do is apply the common sense you spoke of and remember on the old Pos grounded tractor THE TRACTORS POS BATTERYS POST IS WHATS ATATCHED TO THE TRACTORS IRON FRAME while the tractor batterys Neg post is whats wired to the starter switch or solenoid..... Soooooooooooo one would first attach the black negative jumper cable (the one attached to truck batterys - post) to the starter post or the starter side (NOT to battery) of the starter switch or solenoid........Then quicky and hard momentarily jump the red Pos jumper cable (one attached to truck batterys + post) to the tractors iron frame somewhere close to the starter NOT anywhere near the battery !!!!!!!!

5) DO NOT LET THE TRUCK AND TRACTOR COME IN CONTACT WITH EACH OTHER

NOTE in theory and if all is well and correct, this way youre not actually ever hooking the batterys together (even safer) because the tractors switch or solenoid is open so youre ONLY jumping the starter motor Yayyyyyyyyyy

The method above should cause the tractors starter to crank so as long as the tractor ignition is on and its battery has enough energy to power up the ignition (unless if a mag nones required) she ought to start AND THIS IS RELATIVELY SAFE, MUCH SAFER THEN JUMPING A 12 VOLT BATTERY TO A 6 VOLT BATTERY WHICH IS VERY VERY WICKED AND DANGEROUS ......This way your ONLY powering the tractors starter NOT its 6 volt battery (provided the tractors switch/solenoid isnt closed)

Again, this is NOT to argue and Im sure you know what you meant, its just Im afraid some here (with no electricl background) may get confused by your wording

God Bless yall n be safe now

John T

Sounds like you are another lucky to be safe you just dont jump 6v with 12v anyway unless you just dont care for your eyes and the rest of your body along with someone else standing nearby.

Grab it up at the starter button battery cable side and make darned sure you keep your polarity straight.

I've been doing this for 50 years with no ill effects.

Allan

Simple!

Change ALL yer 6 volt stuff to 12 volt NEG. ground and you won't have to worry about it again.

Any way you hook cables is dagerous if starting from ground be sure to triple check to make sure tractor is out of gear. I always try starter with ignition off to make sure it is out of gear. Knew 2 people that are in theie grave from tractor starting in gear with them standing beside it, have had close call myself.