Jump starting a van…
Discussion
The Mad Monk said:
Penelope Stopit said:
Connect jump leads, start Astra and run at 2000 to 3000 RPM for 5 minutes, stop Astra, try to start van
Connect jump leads, start Astra and run at 2000 to 3000 RPM for 5 minutes, leave Astra running, try to start vanE-bmw said:
Start Astra, connect jump leads, run at 2/3000 rpm for 5 mins, leave Astra at 2/3000 rpm, start van.
Make cup of tea, have a chin wag with friend, spend 10 minutes trying to find keys to Astra, spend 20 minutes trying to remember where jump leads are, start Astra, connect jump leads, belch NOX fumes out the Astra for 5 minutes, go back inside, have another cup of tea, try to start van, scratch heads when nothing happens, have another cup of tea, recheck leads, realise not making full contact with metal bits, laugh and call each other jovial names, try to start van again, nothing happens, have another cup of tea, call out the breakdown service, have another cup of tea.mickyh7 said:
So who's right then?
And why?
Genuine question.
We are each biased & no one is particularly wrong but my take is as follows.And why?
Genuine question.
Why start van first? So that you aren't connecting a possibly completely flat battery to a hopefully charged one & therefore not damaging both in the process.
Why keep Astra at 2/3000 while starting van? So that the Astra can still be supplying good current to the van while starting, and not drain the Astra battery.
Everything else is the same really.
No different to doing a petrol vehicle.
Jump started my Sprinter (208CDi) a few times over the years using various sources incl petrol & diesel cars & separate batteries.
Good quality heavy duty jump leads are a must, not the weedy thickness of a shoelace type rubbish often seen & sold in the cheap stores.
Jump started my Sprinter (208CDi) a few times over the years using various sources incl petrol & diesel cars & separate batteries.
Good quality heavy duty jump leads are a must, not the weedy thickness of a shoelace type rubbish often seen & sold in the cheap stores.
brillomaster said:
one question i've wondered - what exactly happens if you try and jump start a car with undersized jump leads? fiery death, or just no starty?
tried googling it, but i just get results for what happens if you connect to the wrong terminals.
No starty and/or very hot leadstried googling it, but i just get results for what happens if you connect to the wrong terminals.
Almost any of the above will work.
Unless the donor car's battery is borderline f
ked it will start fine if you connect the leads first, and I have never had an issue with 'surge loading' when connecting the leads to a running car, or jumping while the donor car is running. Nor have I ever waited more than around a minute.
A 2l desal van has very similar starting needs to a 2ltr diesel can, and while I have some nice leads in the garage, I've had no issues jumping all sorts with the £9 own brand stters that live in the car (lighter and smaller to carry) they are just fairly short!
In a pinch and if the vans battery is ok condition just flat, you could likely get a start of a bit of 2.5 twin and earth if you left it ten mins.
Daniel
Unless the donor car's battery is borderline f
ked it will start fine if you connect the leads first, and I have never had an issue with 'surge loading' when connecting the leads to a running car, or jumping while the donor car is running. Nor have I ever waited more than around a minute.A 2l desal van has very similar starting needs to a 2ltr diesel can, and while I have some nice leads in the garage, I've had no issues jumping all sorts with the £9 own brand s
tters that live in the car (lighter and smaller to carry) they are just fairly short!In a pinch and if the vans battery is ok condition just flat, you could likely get a start of a bit of 2.5 twin and earth if you left it ten mins.
Daniel
Scrump said:
brillomaster said:
one question i've wondered - what exactly happens if you try and jump start a car with undersized jump leads? fiery death, or just no starty?
tried googling it, but i just get results for what happens if you connect to the wrong terminals.
No starty and/or very hot leadstried googling it, but i just get results for what happens if you connect to the wrong terminals.
The plastic sheathing can start to melt & you can get quite a lot of smoke!
You can get smoke replacement kits for vehicle wiring harnesses - Lucas part number 530433 - but I don't think they do a size big enough for jump leads
Krikkit said:
Penelope Stopit said:
The reasoning for my method is that it prevents voltage surges being applied to the Astra Alternator and also a sudden massive load on the fan belt
None of that makes any sense...Under normal circumstances, battery good and fully charged, operating a starter motor could drop the battery voltage to as low as 9.6 volts although 10 volts is a more realistic figure
There is nothing electrical in a vehicle that will drop the voltage to 10 volts when the engine is running, the alternator will also cover any loads that are switched on when the engine is running
An alternator isn't designed to cover the massive current draw of a starter motor
Even if a vehicle is fitted with a high output alternator of let's say 120 Amps, instantly loading the battery of a running vehicle with a starter motor isn't a good method as the alternator could instantly be attempting to give its full output
Alternator charging voltage of lets say 14.5 Volts being possibly instantly pulled down to below 12 volts and later shooting back up to 14.5 Volts
The condition and size of the slave battery is obviously a deciding factor
Have never jump started with an engine running, hence have never needed to check for voltage spikes when doing so
Obviously there is a sudden high load on the fan belt, a load that it would never normally have applied to it
Does any of the above make any sense?
Each to their own though
normalbloke said:
In the days of fickle canbus and BCMs,plus their eye watering price for replacement, I now carry a jump pack and will not use my vehicle to jump start another.
Very good method, many moons ago I had HGV slave batteries that could be switched from 12 to 24 or 24 to 12, could be bad news though if using them when hungoverBetter be safe than sorry will never fail you, I or others
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