Thread: Bad Press by the truckload

Well, I answered my own question with a search:


300Tdi Discovery

To Jump Start - Negative Ground Battery WARNING: To avoid any possibility ofinjury use particular care when connecting a booster battery to a discharged battery.


1. Position vehicles so that jump leads will reach, ensuring that vehicles DO NOT TOUCH, alternatively a fully charged slave battery may be positioned on floor adjacent to vehicle.

2. Ensuring that ignition and all electrical accessories are switched off, that parking brake is applied and neutral is selected on a manual gearbox, with an automatic gearbox select neutral (N) or park (P) and then connect the
jump leads as follows;

A. Connect one end of first jumper cable to positive (+) terminal of booster battery.

B. Connect other end of first jumper cable to positive (+) terminal of discharged battery.

C. Connect one end of second jumper cable to negative terminal of booster battery

D. Connect other end of second jumper cable to a good earth point on the engine, NOT TO NEGATIVE TERMINAL OF DISCHARGED BATTERY.
Keep jumper lead away from moving parts, pulleys, drive belts and fan blade assembly.

Originally Posted by Ferret

There is an earth point stud just in front of the starter battery box on the D4. Why is this not a suitable place to attach the jumper cable clamp?

Because I just fitted my Traxide gear,spotlight relay and cuircut breakers there on a bracket there.

The earth points arnt very big,would be difficult to get a decent earthing there with jumper leads.

Andrew

I accept the negative connection point has to be off the battery, but why is it so? To dampen any surge?

And do the jump leads with protection built in make a difference?

Originally Posted by AndyG

I accept the negative connection point has to be off the battery, but why is it so? To dampen any surge?

And do the jump leads with protection built in make a difference?

how would it make any difference, a negative connection point should still lead back to the negative on the battery.

Originally Posted by AndyG

I accept the negative connection point has to be off the battery, but why is it so? To dampen any surge?

And do the jump leads with protection built in make a difference?

I have witnessed 2 battery explosions at work,in both cases the persons connecting the jumper leads were lucky they had sunglasses on and didnt get acid in their eyes.
A flat battery usulay has lost electrolyte and hydrogen gas takes it place,easy to spark a lead and ignite it.

Then there is the surge wich can harm electronics.

Also saw a workmate somehow get his wedding ring between the jumper leads and battery post on a 24V truck.Ring disolved and he has a permanent tatoo these days


On earthmoving gear we try and jump direct to the starter where safe to do so.Much less of a battery explosion risk,and it takes a lot less current to turn the motor over if a big battery is dead.However you MUST make sure the operator is in the chair as this can prevent start in gear mechanisms on transmissions.NEVER SHORT THE SOLENOID TO BATTERY +,the machine can start in gear and drive off!!!!
The new gear now all is ordered with plug in CAT style jump start points for everyones safety after a few near misses.
Andrew

I'm aware of the correct procedure here for jump starting the D3's however, with the help of to much alcohol and a lack of sleep, on 2 occasions I've had brain fart moments and Jump started directly to the battery and have had no problems. Both pre traxide battery install. It doesn't always end in tears...

Andy, its a bit hard to tell from the photo, but it looks like your earth lead from the battery is different to mine (MY13). My BMS module on the negative terminal has a short copper busbar coming out of it which the earth lead is then attached to. It looks like it is there to attach a charger to, but I haven't been game to try it. Does yours have this?

I can take a photo in the morning if that doesn't make sense.

Cheers,
Jon

There is a spare lug on mine that looks like its there to accept another cable,thats where I had the earth clamp on the charger.On a closer inspection,it does look like the BMS is connected to this lug.
Andrew