Starting Cub with 12 volt battery

How much damage can occur starting a cub on a 6 volt system with a 12 volt battery installed on tractor;;;;Thanks

All depend on it is has a mag or a distributor. As for starting only very little if any as for running for a long time if it has a distributor you could burn out the coil and also burn the points. That said I do that type of thing all the time on old tractors just to see what they may or may not need to make them work

LIke Old said, depends upon whether or not you have a magneto or battery ignition.

If a mag, no issues. Have at it, it just won't charge the battery. If you have a battery ignition, it will burn the points unless you add a ballast resistor.

You can do A LOT of damage or NO damage, it depends on how you jump start it.

DO NOT DIRECT JUMP A 12 VOLT BATTERY TO A 6 VOLT BATTERY ESPECIALLY WITH CONNECTIONS MADE N BROKE AT THE BATTERY TOP WHERE EXPLOSIVE GASSES CAN BE PRESENT

A much safer way to jump start a 6 volt tractor is to jump direct to the big stud on the starter itself because thats NOT a connection to the tractor battery because the starter switch (when not activated) is an open circuit. That way the ONLY thing your applying 12 votls to is the starter motor. When you apply 12 volts to the starter (it ONLY for safety) she should reallyyyyyyy spin over fast so if the ignition is on and works thats a safer way to 12 volt jump a 6 volt tractor.

NOTE if its a working magneto ignition that can start the tractor even if the tractor battery is dead or not installed HOWEVER if its a battery powered coil distributor ignition it needs energy to run so the 6 volt tractor battery has to have at least some charge remaining

SUMMARY jump to the starter ONLY and even if it still turns the same direction regardless of battery polarity, I still use the same jumper polarity as the tractor i.e. Pos or Neg ground. If its Pos ground I make the first - connection to the starter stud/post then to start it I make the last + connection to the iron frame close to the starter and not close to the battery.

Nuff said, if I missed anything the other fine gents can add to this.

John T

You can do A LOT of damage or NO damage, it depends on how you jump start it.

DO NOT DIRECT JUMP A 12 VOLT BATTERY TO A 6 VOLT BATTERY ESPECIALLY WITH CONNECTIONS MADE N BROKE AT THE BATTERY TOP WHERE EXPLOSIVE GASSES CAN BE PRESENT

A much safer way to jump start a 6 volt tractor is to jump direct to the big stud on the starter itself because thats NOT a connection to the tractor battery because the starter switch (when not activated) is an open circuit. That way the ONLY thing your applying 12 votls to is the starter motor. When you apply 12 volts to the starter (it ONLY for safety) she should reallyyyyyyy spin over fast so if the ignition is on and works thats a safer way to 12 volt jump a 6 volt tractor.

NOTE if its a working magneto ignition that can start the tractor even if the tractor battery is dead or not installed HOWEVER if its a battery powered coil distributor ignition it needs energy to run so the 6 volt tractor battery has to have at least some charge remaining

SUMMARY jump to the starter ONLY and even if it still turns the same direction regardless of battery polarity, I still use the same jumper polarity as the tractor i.e. Pos or Neg ground. If its Pos ground I make the first - connection to the starter stud/post then to start it I make the last + connection to the iron frame close to the starter and not close to the battery.

Nuff said, if I missed anything the other fine gents can add to this.

John T

John, I absolutely agree with your post, but I believe he is going to use a 12v battery in place of the 6 volt, NOT to jump it.

I would hate to argue with the experts, but since I own a Cub, and know how they are wired, to preveny any damage, you shouldnt connect it to the starter at all, assuming its wired correctly. There is no where to hook to the starter that isnt directly connectd to the battery, since all the power comes from the saddle switch on the starter. In order to do as suggested, youd have to take the battery cable off of the starter all together.

FWIW I agree with you, youre correct, you'll get NO argument from me (maybe some expert will argue). For what I suggest he has to have a starter with an accessible stud/post which has a battery cable leading from it to a push type starter switch (or a solenoid if it has been converted). If he has what I call a saddle mount mechanical push switch (sounds like what youre talkin about) that has the starter contact hidden underneath, then he cant get to it and that type of switch has the big honkin battery cable attached right to it grrrrrrrrrrrr. When I was a used tractor dealer I saw so many farmer Bob jury rigged electric solenoid conversions and/or the pedestal mount push to start switch conversions I couldnt hardly keep up trying to make them half right for resale.

AGAIN DO NOT DIRECT JUMP A 6 VOLT BATERY OFF A 12 VOLT BATTERY ESPECIALLY AT BATTERY TOP, IT CAN EXPLODE

Good info, fun chat

John T

Unless his has been somehow modified, he has a saddle type switch on the starter, which requires the battery cable be attaches straight to the the post. The "expert" wasnt meant as an insult to you, partner! It was a compliment!!

I know exactly what you mean by jury rigged electrical. What I dont understand is why, even if its a 12 volt conversion, or a complete rewire, etc., it isnt done right! I guess if youre too cheap to do it right the first time, you can pay for it the second, or third, or forth........

But John he did not say anything about jumping it he said putting a 12 volt battery on it which I have done many times on many tractor and for a short time never hurt any thing. Now ya if you where going to leave it that way you need a ballast resister etc.

Thanks, no problem I just enjoy sparky chats.

In many years of sales I'd say I saw more (electrical mods) done half a$$ed then right actually. It costs a bit more to do it right and the funny thing is how so many otherwise darn good farm n shade tree mechanics (much better then I) ARE JUST OUT TO LUNCH when it comes to basic electrical knowledge. Im NOT knocking them, just pointing out they may be execellent mechanics yet they short change the electrical modifications.

As I'm sure you're aware, a starter shop (but not many left compared to years ago) can take those starters intended for saddle switches and replace that exposed copper button with a stud for use with the H and M type pedestal push start switches or electrical solenoids.

To add to the posters original question based on your excellent input, and ifffffffff he still has the saddle switch, I guess if I just had to quickly jump start it AND IF IT HAS A MAGNETO IGNITION it would be easiest to just remove a battery cable (safest to remove the ground cable where it bolts to frame) up near the battery,,,,,,,,,,,, then make the temporary jump as earlier described to start her,,,,,,,,, then replace the battery cable to frame connection. I say at the frame ground conenction cuz I dont like to make sparkies at the top of the batetry.

Funnnnn chattin at ya, hope we have helped n not cornfused......

John T

Good Mornin Rich, Its true (ignition related) a short time may not overheat a 6 volt coil (if its a distributor ignition, if Mag no problem) but if it has a charging system I just cant recommend him to put a 12 volt battery in place of a 6 volt. I'm like you in years of farming and used tractor dealing Ive done all sorts of short term "jury rigs" but Id hate for him to do harm to the charging system components based on me saying SURE NO PROBLEM. That being said he or you feel free to do as you like to your own tractors I SURE HAVE OVER THE YEARS LOL

Take care of things down south there

John T

Ya but answer me this. Wouldn't the V.R see an over charged battery if the charging system was working and then in turn turn the generator off so to speak and because the V.R. did is job then no harm would happen in theory that is

FUN CHAT RICH, here goes:

Yeppers, In THEORY AT LEAST, the Cutout Relay (which connects battery to genny) shouldnt close until genny voltage exceeeds battery voltage, but the open "relatively" unloaded voltage output of a genny is much higher then it is compared to what it becomes once coupled up to a load/battery. Sooooooo if??????? that relay latched then the fields see 12 not 6 volts and draw twice the current they were designed for (which could cause overheating) HOWEVER you raise a valid point that the voltage regulators function (if it had that versus a cutout relay and light switch system) should regulate and limit the field current so as to avoid genny harm. YES IT SEES A WELL CHARGED BATTERY AS YOU MENTIONED in theory at least NO WARRANTY

But I still just dont like the idea of a 12 volt battery wired to a 6 volt charging system cuz if he lets the smoke out then Im the bad guy grrrrrrrrr

BUT if he were to simply unhook the wire off the BAT on a Cutout Relay or a Voltage Regulator (to alieve my worries above) and if he has a Mag Id say he can stick a 12 volt battery in her and not turn on any lights and run her till the cows come home as all the battery is then doing (until it eventually runs down from starting her) is temporarioly run the staretr motor now n then

Oh well, we pretty well beat this to death but were havin fun

John T

Of course there is also this. If it where one of the cubs that had the starter generator on it then yep all sorts of funny things could happen and since he did not say what year it was very hard to know for sure what may or may not happen

The Cubs with a starter/generater are 12 volt.

Alvin, welcome to the site, but I have to disagree with you. I have a 1949 Farmall cub. She is 6 volts, and has a starter and a generator. The newer cubs may be 12 volts, but the older ones are 6v.

I bought her off the neighbor's wife after he passed away. My dad remembered when the neighbor bought it new. It is 100% original except for the coil. It even still has the original cloth wiring harness. So, this old girl is about as original as it gets.......

Was not sure on that since it ha been a decade since I messed with one of those type

I believe Old was commenting on Cubs with the combined starter-generator. Alvin correctly pointed out that all of them with the starter-generator are 12-volt. A '49 Cub could have had a starter and a generator, but would not have a starter-generator.

Well, for two cents worth… just don't like connecting 12 volt batteries to 6 volt systems. You make a mistake and either it costs a lot of money or it can cause serious damage to machine and operator. Have another 6 volt battery handy. I manage by jump starting off another tractor which has two 6 volt batteries in series, so I just connect from one and then there is no problem. All that said, on a magneto ignition engine, surely it should not be difficult to hand start the tractor?
SadFarmall

Alvin, my apologies, I misread your post. My bad.

Cubs don't have a combination starter generator. Cub Cadets do.