Omega Owners Forum
Chat Area => General Car Chat => Topic started by: Toledodude1973 on 16 January 2013, 17:53:06
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Can someone help with this one please, i tried to start a car using leads from my van today with little success,connected red to red and then neg.(good bat) to point on dead car near engine block. I'm using good quality leads but they just got hot (with some smoke)so i had to abandon it. The dead cars bat. was completely dead not even a dashboard light flicker.Any ideas?
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What car was it?
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And what van
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We are starting a corsa with a transit van thanks for reply
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Both -ve earth, so should be OK.
Sure leads were right way round? Don't rely on wire colours, check the +ve and -ve symbols on battery.
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Both -ve earth, so should be OK.
Sure leads were right way round? Don't rely on wire colours, check the +ve and -ve symbols on battery.
Although that would only be a problem if both cars were earthed
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The corsa bat seemed completely flat, and apparently pretty new, cables were heavy type, used them many times before, cant understand it
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The corsa bat seemed completely flat, and apparently pretty new, cables were heavy type, used them many times before, cant understand it
Could be that the Corsa's battery is totally fubar and no amount of power is going to revive it ???
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If corsa battery was completely fubar would that cause leads to heat up?
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If corsa battery was completely fubar would that cause leads to heat up?
It could do if the battery has shorted itself.
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just one last thing ,if when the corsa had a recent new battery the terminals were wired as positive earth what effect would this have on the corsa(sorry or being a bit thick)
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dead corsa,praise the lord ;D ;D ;D
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Looks like it must be the battery then,as it had been used that morning thnks for help
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Engine seized?
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just one last thing ,if when the corsa had a recent new battery the terminals were wired as positive earth what effect would this have on the corsa(sorry or being a bit thick)
Not possible. It would not have worked whatsoever with a Pos Earth.
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I always put both leads from battery to the battery ie pos to pos and neg to neg that should give you good contact, and have the donar vehicle running
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I always put both leads from battery to the battery ie pos to pos and neg to neg that should give you good contact, and have the donar vehicle running
Not the best way as much of the "donor" energy is now used trying to "recharge" the flat battery, effectively it is a resistance in the circuit.
Better to connect just the positive to the battery and the negative to a good 0v (earth :( ) on the engine ... usually a lifting bracket is a good point. Bolt heads are not usually good as they are often covered in an oily film as best .. :)
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I always put both leads from battery to the battery ie pos to pos and neg to neg that should give you good contact, and have the donar vehicle running
Not the best way as much of the "donor" energy is now used trying to "recharge" the flat battery, effectively it is a resistance in the circuit.
Better to connect just the positive to the battery and the negative to a good 0v (earth :( ) on the engine ... usually a lifting bracket is a good point. Bolt heads are not usually good as they are often covered in an oily film as best .. :)
they told us at school lifting eyes are best... but then theyre not always accessable ::)
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I always put both leads from battery to the battery ie pos to pos and neg to neg that should give you good contact, and have the donar vehicle running
Not the best way as much of the "donor" energy is now used trying to "recharge" the flat battery, effectively it is a resistance in the circuit.
Better to connect just the positive to the battery and the negative to a good 0v (earth :( ) on the engine ... usually a lifting bracket is a good point. Bolt heads are not usually good as they are often covered in an oily film as best .. :)
Yes but if the battery is that discharged then atleast it will charge it up quicker and then give it a chance
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I always put both leads from battery to the battery ie pos to pos and neg to neg that should give you good contact, and have the donar vehicle running
Not the best way as much of the "donor" energy is now used trying to "recharge" the flat battery, effectively it is a resistance in the circuit.
Better to connect just the positive to the battery and the negative to a good 0v (earth :( ) on the engine ... usually a lifting bracket is a good point. Bolt heads are not usually good as they are often covered in an oily film as best .. :)
Yes but if the battery is that discharged then atleast it will charge it up quicker and then give it a chance
But you don't want the battery to be charged ..yet .. you want all the available energy to go to start the engine ... then the alternator can charge the battery far more efficiently.. :)
and the amount of charge put in is negligible anyway .. it is far more of a drain on the good system than a charge on the bad !!
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I disagree. You want to get some charge into the battery on the disabled vehicle because there is probably too much resistance in the jump leads to power the starter motor directly, especially if the leads are a bit cheap. You need some contribution of current from the flat battery too, and that means charging it a little first. That means connecting as close as possible to the battery, really.
Get a car with a properly flat battery (as I had last night ::)) and you'll find it needs the jump leads connected for a few minutes with the donor engine running before it will turn over.
The main reason for the recommendation to make the final negative connection to a lifting eye or similar is that there will be a spark when you connect it, and the battery is a potential source of hydrogen and oxygen, so could explode given a spark at its' negative terminal.
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I disagree. You want to get some charge into the battery on the disabled vehicle because there is probably too much resistance in the jump leads to power the starter motor directly, especially if the leads are a bit cheap. You need some contribution of current from the flat battery too, and that means charging it a little first. That means connecting as close as possible to the battery, really.
Get a car with a properly flat battery (as I had last night ::)) and you'll find it needs the jump leads connected for a few minutes with the donor engine running before it will turn over.
The main reason for the recommendation to make the final negative connection to a lifting eye or similar is that there will be a spark when you connect it, and the battery is a potential source of hydrogen and oxygen, so could explode given a spark at its' negative terminal.
I agree you leave the system standing a few minutes .. but that doesn't actually "charge" the dead battery at all .. it just changes what is happening on the surface of the plates and reduces the resistance.
Put it this way ... if the "donor" alternator is rated at 120 amps ... and you connect it to your dead battery for 4 minutes (and who waits that long ? most folks don't even wait 2 minutes) then it "puts in" a massive .... 8 amp/hours !!! ... which is about as much use in starting an engine as tits on a bull !!!
Just my views .. nowt else .. :)
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I disagree. You want to get some charge into the battery on the disabled vehicle because there is probably too much resistance in the jump leads to power the starter motor directly, especially if the leads are a bit cheap. You need some contribution of current from the flat battery too, and that means charging it a little first. That means connecting as close as possible to the battery, really.
Get a car with a properly flat battery (as I had last night ::)) and you'll find it needs the jump leads connected for a few minutes with the donor engine running before it will turn over.
The main reason for the recommendation to make the final negative connection to a lifting eye or similar is that there will be a spark when you connect it, and the battery is a potential source of hydrogen and oxygen, so could explode given a spark at its' negative terminal.
:y :y
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To start a car you might need a current of the order of 300 Amps for 3 seconds. That's only 0.25 Amp hours of charge, so 8 Ah is plenty. ;)
A typical set of jump leads simply won't pass that sort of current, hence the wait required, during which time you are charging the battery..
Batteries accept charge or lose it, depending on the direction of current flow, and that's all they do. Place a fully charged battery in parallel with an empty one and current will flow and the empty battery start charging, more so if the charged battery is itself being charged by an alternator meaning that it has upwards of 14V across it.
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So would you agree after putting jump leads on (neg.lead to engine lift brackets)and they heat up immediately the dead has probably shorted out.
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So would you agree after putting jump leads on (neg.lead to engine lift brackets)and they heat up immediately the dead has probably shorted out.
Yes, sounds like you've got a short at the dead car's end or maybe the starter solenoid has jammed in the engaged position?
I suppose it's possible that if the battery is completely flat in that vehicle it might take a considerable current. Enough to heat up a cheap pair of jump leads? Not sure.
I think I'd give it a charge with a mains battery charger whilst monitoring the voltage across the battery. If it's taking a good few amps of charge you should see the voltage rise quite quickly to around 12V. If it's sitting much lower than that and a gentle charge doesn't raise it you either have a short in the vehicle somewhere or an internal short in the battery (may even be only one cell meaning it levels off at 10 Volts). Charging the battery disconnected from the vehicle will reveal if it's a problem with the battery itself.
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Thanks Kevin, a full answer as always on OOF cheers