Jump starting Positive Ground

   / Jump starting Positive Ground #1  

heron

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Sep 28, 2009
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I'm about to acquire my grandfathers 1955 Allis Chalmers HD5 delivered next week. The dozer had a 6 volt system but my father has replaced it with a 12V battery and removes the battery when not in use. Problem is when it gets here the battery may not be charged enough to start the dozer on the flatbed.
Anyone know how to properly jump this 12V from my truck? I'm thinking I would have to go pos terminal to pos terminal and negative to negative regardless of configuration but then I worry about blowing up my battery or my computer in my truck...Any ideas?
 
   / Jump starting Positive Ground #2  
We jump positive ground Ford Tractors and Case Dozer all the time. The best thing to do is get the battery charged if possible but if you must simply hook up the cables as normal to your truck and then put the red positive one on the equipments chassis (ground) and the black negative on the equipments battery to the correct terminal on the battery.

Chris
 
   / Jump starting Positive Ground #3  
Reverse the polarity of the charger/jump vehicle's cables at the positive ground tractor. (Black on Positive-Red on Negative terminals. Do not let any metal touch between either vehicle
 
   / Jump starting Positive Ground #4  
Your thinking is correct. Connect positive from your truck battery to positive of the dozer battery and negative to negative of each battery. Whether the dozer is positive or negative ground, you are safe if you make your connections directly to the battery terminals, + to + and - to -. As amigauser says, do not let any part of your truck touch the trailer or dozer just in case the dozer is positive ground.
 
   / Jump starting Positive Ground
  • Thread Starter
#5  
Reverse the polarity of the charger/jump vehicle's cables at the positive ground tractor. (Black on Positive-Red on Negative terminals. Do not let any metal touch between either vehicle

This dozer is coming from South Windsor.
Can you be more specific? I've heard horror stories of tops of batteries being blown off and I do remember doing it with my dad about 30 years ago but I've forgotten since then... I remember hooking to the starter directly but I want to be very careful.
I probably will end up using one of those mobile jump packs so do I hook the positive side of the jump pack up to the negative terminal of the battery in the dozer and the negative lead from the jump pack to the positive side of the battery in the dozer?
 
   / Jump starting Positive Ground
  • Thread Starter
#6  
Your thinking is correct. Connect positive from your truck battery to positive of the dozer battery and negative to negative of each battery. Whether the dozer is positive or negative ground, you are safe if you make your connections directly to the battery terminals, + to + and - to -. As amigauser says, do not let any part of your truck touch the trailer or dozer just in case the dozer is positive ground.

The dozer is a positive ground for sure. It is an old 6V system. Not sure how my dad did it but he simply put in a 12V battery. I don't think the generator can charge it but he never uses the dozer on a daily basis so he just takes out the battery and recharges it each time he uses the dozer.
 
   / Jump starting Positive Ground #7  
You may find that using jumper cables on a jumper battery pack or even from your truck is unsatisfactory. I suspect your father actually installed a 12v battery and hooked up the battery cables directly to its posts. Starting any diesel takes a lot of current, especially if you have glowplugs to cycle. The jumper cable alligator clips may become very hot or arc and lose contact. It would be best to remove your battery from your vehicle and install it in the dozer long enough to get it going, then remove the battery and put it back into your truck. From your description, that's what your father did.
 
   / Jump starting Positive Ground #8  
I probably will end up using one of those mobile jump packs so do I hook the positive side of the jump pack up to the negative terminal of the battery in the dozer and the negative lead from the jump pack to the positive side of the battery in the dozer?

NO.

You hook positive to positive and negative to negative, regardless of the grounding on the dozer.
 
   / Jump starting Positive Ground
  • Thread Starter
#9  
NO.

You hook positive to positive and negative to negative, regardless of the grounding on the dozer.


Okay, is this the best way to do it? I think I remember my dad running the positive jumper from his truck and clipping it on the track and then running the negative jumper right to the starter. Then we'd fire it up from the seat.
Seems like if I ran the positive jumper to the track of the dozer it would blow my battery to smitherines...This stuff gets sooo confusing. I just remember my dad complaining that one time he blew the top of one of the batteries off... I don't need this to happen when the dozer is 3' up on a flatbed and the driver is waiting for me to unload it...
 
   / Jump starting Positive Ground #10  
Okay, is this the best way to do it? I think I remember my dad running the positive jumper from his truck and clipping it on the track and then running the negative jumper right to the starter. Then we'd fire it up from the seat.
Seems like if I ran the positive jumper to the track of the dozer it would blow my battery to smitherines...This stuff gets sooo confusing. I just remember my dad complaining that one time he blew the top of one of the batteries off... I don't need this to happen when the dozer is 3' up on a flatbed and the driver is waiting for me to unload it...

I have a 1960 MGA that is positive ground and have jumped it several times. You have 2 optiions. Direct connect from one battery to the other. Pos to pos (red) and neg to neg (black). Just like you would connect it to jump start any other vehicle. The other is pos (red) on the truck battery to the frame or track of the dozer (red) which is positive on the dozer because of the reverse grounding, and then neg (black) from truck battery to neg (black) on dozer battery.
 
 
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