Jump starting tractors

[K5lwq]

Ok I will share a funny story. My uncle had a VW bug. My aunt a Pontiac. He had a dead battery and was running a little late to work. So he pushed the VW into the street and asked my aunt to use her Pontiac to push him off.

He gave her the instructions. He told her to get behind him and get up to 20mph then back off. He would take it from there.

So she backs out and drives around him and thinks where in the world is she going? She goes around the block and he sees she is coming up behind. He thinks she just went around the block to line up better.

He watches her coming up on him in the rear view mirror and realized very quickly she was not slowing down. Then Boom! She nails him. He gets out and says what the heck! She said you told me I had to get up to 20MPH!

 

[zzvyb6]

The 'problem' is that dead tractor batteries have HUGE capacitance. So, not only are you trying to feed the high current starter, but also trying to feed the dead battery. So, disconnect the dead battery before jumping from any other source.

 

[hube2]

As someone else said, invest in a jump start pack, some of the best investments I've ever made. I have one in each car. Don't have a separate one for the tractor since my car is always where I am. You just gotta remember to charge them regularly and you keep them in the car in the winter you need to do this more often than they recommend. Mine have USB ports, car lighter type sockets, AC power sockets, and air compressor and an LED light.

Amazon.com: DieHard 71688 1150 Peak Amp 12V Jump Starter with USB/12V Portable Power Ports and 100PSI Air Compressor : Everything Else

Amazon.com: DieHard 71688 1150 Peak Amp 12V Jump Starter with USB/12V Portable Power Ports and 100PSI Air Compressor : Everything Else

www.amazon.com

 

[deserteagle71]

Damn! Can't believe I've been doing this all wrong for the past 60 years!

 

[WranglerX]

The 'problem' is that dead tractor batteries have HUGE capacitance. So, not only are you trying to feed the high current starter, but also trying to feed the dead battery. So, disconnect the dead battery before jumping from any other source.

Where is "Myth Busters" when you need them....

 

[grsthegreat]

Say what..... I never disconnect a dead battery....ever. Never had any issues

 

[Cougsfan]

I too have not been following any of these hallowed procedures for the last 60 years. I just connect the jumper cables from whatever has a good battery to start whatever has a bad battery. Never had a problem yet. Either I am extremely lucky or this thread is overthinking jump starting. I saw my son jump start his Honda car using a 20 volt portable drill motor battery. Probably not the proper thing to do, but it worked.

 

[Jstpssng]

Last year I jumped a Honda using a piece of wire from a portable battery charger. Rather than boost it, I used my alternator to charge his battery. Like many others, I'm dismayed to learn that I've been doing it wrong all of this time; in my case though, it's only been 40 years or so. I did manage to burn up the starter in my snowsled though, trying to boost it with my pickup. That battery had been dead for years, I just wanted to see if the starter worked.

 

[Fallon]

The 'problem' is that dead tractor batteries have HUGE capacitance. So, not only are you trying to feed the high current starter, but also trying to feed the dead battery. So, disconnect the dead battery before jumping from any other source.

Yes batteries have lots of capacitance. Alternators (voltage regulatirs) rely on that capacitance to function properly & smooth out voltage output. Spinning an alternator without a battery attached is a great way to fry them very quickly.

 

[DutchInNZ]

The 'problem' is that dead tractor batteries have HUGE capacitance. So, not only are you trying to feed the high current starter, but also trying to feed the dead battery. So, disconnect the dead battery before jumping from any other source.

If you then have the jumped engine running and you disconnect the cable, you may fry the rectifying diodes and the electronic circuitry in the alternator because those are made for low voltages while an alternator without the tension limitation of a battery can easily go over 60 Volts. Have the jumping engine running for a few minutes to start charging the empty battery a bit before you start the jumped engine.