Billbigwheels:
When you jump start anything you only double the amps, not the volts.
Unless you connect them in series. I have done this with a 12-volt system where both batteries were a bit low and the diesel wouldn’t start. It sure made the starter motor whizz round and fired it up in no time. Not recommended though.
Heisenberrg:
Oh how I yearn for the days when drivers helped each other out.
Aye lad, back then somebody would always lend you their starting handle.
Pete.
What kind of a driver don’t know how to jump start a truck any job you get now pulling a fridge the first thing you are thought is how to jump start on long distance work its the same principle on trucks
Shame on you for first of all for judging him before he even asked and then bottle it because you had not got the confidence to do it
When I read the heading I thought this post was going to be about ■■■ between two drivers!
I’ll get my coat!!
kickstart:
When I read the heading I thought this post was going to be about ■■■ between two drivers!
I’ll get my coat!!
Kinda what I said ! 
chloelovesfur:
Never seem to be in the right placeDig the self anaylitical stuff though !
Ummmmm… Not really. Sounded like taking disapointment from the humiliation.
Then you go all …Sigmund Freud on us.
It gets worse my truck has a dedicated 24volt connection by the batteries and instructions how to jump start in the manual.
Thanks for all the tips a day of self flagellation with a sandpaper covered ■■■■■ is in order.
dave docwra:
Simple way & this will not cause any problems.
1.Turn off the vehicle you are using to supply battery power
2. Connect the jump leads in the correct order ensuring you connect Negative to Negative & Positive to Positive, This the important Bit, you must not connect to the terminals that connect the two batteries together
3.Turn on headlights of the vehicle that is being jump started, if it starts allow to idle for a few minutes & then disconnect leads, if it does not start go to step 4 after turning off head lights
Start slave vehicle & allow to run for a few minutes at about 1000rpm, allow to idle, turn on headlights of stranded vehicle & start, allow vehicle to idle for a few minutes & remove leads
Drive normally for about 10 minutes & then turn head lights off if in daylight.
Hope that helps Dave.
Thanks Dave really handy information.
Dipper_Dave:
dave docwra:
Simple way & this will not cause any problems.
1.Turn off the vehicle you are using to supply battery power
2. Connect the jump leads in the correct order ensuring you connect Negative to Negative & Positive to Positive, This the important Bit, you must not connect to the terminals that connect the two batteries together
3.Turn on headlights of the vehicle that is being jump started, if it starts allow to idle for a few minutes & then disconnect leads, if it does not start go to step 4 after turning off head lights
Start slave vehicle & allow to run for a few minutes at about 1000rpm, allow to idle, turn on headlights of stranded vehicle & start, allow vehicle to idle for a few minutes & remove leads
Drive normally for about 10 minutes & then turn head lights off if in daylight.
Hope that helps Dave.
Thanks Dave really handy information.
+1
Dipper_Dave:
driver approaches me wearing thick rubber gloves (the ones used for disposal of bodies in acid baths)
Glad you stayed alive to tell us the tale 
In a previous job of mine we used to jump start vehicles using an Anderson lead. Assuming both units have Anderson plugs, just connect two units together and it always worked, dead easy.
The big mistake people used to make was connecting pos to pos and neg to neg on both batteries.
The neg lead should be earthed to the vehicle (chassis or something capable)rather than the neg terminal on the vehicle being jumped.
No idea about newer vehicles. Never had the problem arise.
Dr Damon:
The big mistake people used to make was connecting pos to pos and neg to neg on both batteries.
The neg lead should be earthed to the vehicle (chassis or something capable)rather than the neg terminal on the vehicle being jumped.No idea about newer vehicles. Never had the problem arise.
Why would you not use the battery terminal?
Power drain is a huge problem on the new Volvos so jump starts are a regular event if parked up in it for a day or so.
It’s no problem for the truck as long as there there is someone about to give you a jump.
"Provided by Volvo Trucks
Emergency starting
Starting with starting cables
If the truck’s batteries have been fully discharged, the truck may need electrical starting assistance from another vehicle or other batteries. Always use another vehicle or other batteries to help start the engine. The jump leads must be able to handle 1000 A for at least 30 seconds.
1 Turn the starter key to the 0 position.
2 Make sure that the booster battery has 24 V total voltage or 24 V system voltage.
3 Switch off the engine of the “assisting vehicle” and make sure that the vehicles do not touch one another.
4 Connect one clamp from the red cable to the positive terminal of the booster battery. The positive terminal is marked in red, P or +.
5 Connect the red cable’s second clamp to the positive terminal on the extensible rod below the red knob (see figure) on the vehicle in need of help.
6 Connect one clamp from the black cable to the negative terminal of the booster battery marked in blue, N or -.
7 Connect the black cable’s second clamp to the screw marked with -(see figure).
8 Start the engine on the “assisting vehicle”. Let the engine run for some minutes at a higher speed than normal (approx. 1000 rpm).
9 Start the engine on the other vehicle.
10 Remove the clamp on the black cable from the grounding point.
11 Remove the clamp on the black cable from the negative terminal on the booster battery.
12 Remove the red cable.
CAUTION Start aid units must not be connected, as these can produce very high voltage levels, which in turn can damage control units.
For positive connection, pull out the red knob. Negative connection on the marked screw.
NOTE The battery contains acid which is corrosive and toxic. It is therefore important that the battery is handled in an environmentally sound manner. A Volvo workshop can help you with this.
End of Volvo Quote.
In summary you connect in a circular pattern starting at the power source i.e.
Red on good battery to
Red on bad battery…
Black on bad battery to
4.Body on good truck.
(Good to Bad, Bad to Body)
Do this in reverse order to disconnect.
Never connect different colours.
Never touch the terminals that are just connecting the battery set together.
Hmm…, I wonder if this has been any help. Apologies if not.
dave docwra:
Dr Damon:
The big mistake people used to make was connecting pos to pos and neg to neg on both batteries.
The neg lead should be earthed to the vehicle (chassis or something capable)rather than the neg terminal on the vehicle being jumped.No idea about newer vehicles. Never had the problem arise.
Why would you not use the battery terminal?
Because if you do it can cause battery explosions.
I know a fitter who ended up in hospital with acid burns and bits of battery stuck to his face.
Hurry up and wait is saying the same.
Dr Damon:
dave docwra:
Dr Damon:
The big mistake people used to make was connecting pos to pos and neg to neg on both batteries.
The neg lead should be earthed to the vehicle (chassis or something capable)rather than the neg terminal on the vehicle being jumped.No idea about newer vehicles. Never had the problem arise.
Why would you not use the battery terminal?
Because if you do it can cause battery explosions.
I know a fitter who ended up in hospital with acid burns and bits of battery stuck to his face.Hurry up and wait is saying the same.
Yes, a big NO NO these days. Always use the chassis or engine for earthing. I don’t know about trucks these days but a lot of cars can have problems jump starting them. Range Rovers can blow various electrical items unless the engine is left to idle for several minutes after starting and the leads left connected, my Peugeot states in the handbook that it must not be used to jump start another vehicle or serious problems can arise. Oh for a return to the simple times! 
Pete.
Dr Damon:
dave docwra:
Dr Damon:
The big mistake people used to make was connecting pos to pos and neg to neg on both batteries.
The neg lead should be earthed to the vehicle (chassis or something capable)rather than the neg terminal on the vehicle being jumped.No idea about newer vehicles. Never had the problem arise.
Why would you not use the battery terminal?
Because if you do it can cause battery explosions.
I know a fitter who ended up in hospital with acid burns and bits of battery stuck to his face.Hurry up and wait is saying the same.
Put the Negative cable on last to the slave vehicle if you are not sure if the gas has not dispersed, a few vehicles have no Earthed chassis & some do not use the chassis as the main earthing point, but can use the bell housing/engine area as the main earth point & then run lighter earths out to the required areas, this is where a problem can occur by putting a strain on these points & burning them out, as always give the stranded vehicle batteries some time & air for any explosive gas to disperse.
Don’t forget when you change a battery there is a risk that it may go bang,
To avoid getting bits of battery in your face, it is best never to stand over any battery when jumping or changing it, in my experience I have only ever seen the top depart from the casing & sides split when things have gone wrong.
Its actually fine to connect the leads battery to battery and will create a better connection.The only reason it wasnt really recommended to put the leads direct to the terminals was to avoid sparking and causing an explosion from old school lead acid batteries giving off gases, sealed batteries have now more or less aleviated this problem.With the engine off connect the red positive lead to the + terminals and the black - lead to the flat batteries last. Start the engine and allow to idle for a minute before turning over the flat truck. No need to rev the engine as full power from the alternator will be there as its detecting a drain with the connected leads.
Ive done this twice with my 3month old FH to start trucks in our yard and its been fine. New trucks may well have many complex electronic systems but these are all surge protected. Battery technology may well hve moved on with gel and silver calcium batteries but charging circuits have barely changed over the years…
AndrewG:
Its actually fine to connect the leads battery to battery and will create a better connection.The only reason it wasnt really recommended to put the leads direct to the terminals was to avoid sparking and causing an explosion from old school lead acid batteries giving off gases, sealed batteries have now more or less aleviated this problem.With the engine off connect the red positive lead to the + terminals and the black - lead to the flat batteries last. Start the engine and allow to idle for a minute before turning over the flat truck. No need to rev the engine as full power from the alternator will be there as its detecting a drain with the connected leads.
Ive done this twice with my 3month old FH to start trucks in our yard and its been fine. New trucks may well have many complex electronic systems but these are all surge protected. Battery technology may well hve moved on with gel and silver calcium batteries but charging circuits have barely changed over the years…
I’m a little old school on his sort of stuff and was taught to use an earth point on the vehicle rather than the battery simply because you could get a larger surface area to contact, plus, in the olden days the terminals were often covered in grease.
Disagree with the point on picking up he revs though. If you’ve got a battery that’s really low, it can drag the voltage on he good battery down to he point where it stays the good vehicle. IME though, that tends to suggest a faulty battery.
back in the day we had starting handles never had a flat battery problem in those days 