Starting car on these cold mornings, any tips?!

[cpjitservices]

BM's are good cars mate, however for now Im sticking with my Picasso 2 Litre HDI. I had no chance of starting it when the battery became weak because of the cold weather! No chance at all!

[Disaster]

Wicked! Took for a big spin last night around 10pm, hit the motorway and all that. Started first time! Hopefully that'll do it!

[PotNoodleTech]

Are there other things I can do to help get it going - and I've also been looking at heaters...

 

Cheers chaps/chapettes

 

Just go to Halfords and get a new battery fitted mate. Batteries sag their voltage in the cold weather, your battery sounds like it's old enough that it's sagging it's voltage below where the car can reliably start.

 

New battery = ignition click engine boom drive drive!

[eyetea]

Can you get a more powerful battery in there? When I drove my Morris it had a feeble small battery in, replaced it with a battery that was more suited to starting a larger diesel car and never had a problem again!

[Disaster]

I think it was down to a combination of things; cold weather, just been on holiday, short drives to work, a failed start that drained the battery. Since I've had the battery in I can't remember having an issue up until now.. I'm hoping it will be ok from now on.

[cpjitservices]

If not get a new battery with higher amps... And if you've got a multimeter you can check how your current battery is doing. Check the voltage before you start the car (preferably on a cold morning) - it should be 14.5 but if its starting to be a weak battery it will be lower. Any lower and you know the engine isnt going to start - unless the alternator can get charge to the battery quick enough.

[3s-gtech]

That's not correct - the battery voltage before starting the car (assuming it has been left for a while) should be a smidgen over 12 volts. 14+ volts is the charging voltage of the alternator, so if you measure it after starting the engine and running for a while to charge back up it should reach 14v +.

 

Best way to check a battery is with a drop tester. This hits it with a measured load, and has a colour gauge to show battery condition.

 

unless the alternator can get charge to the battery quick enough.

 

Wha? The alternator won't be charging the battery at all unless the pulley gets up to sufficient RPM, i.e. when the engine is running.

[cpjitservices]

That's not correct - the battery voltage before starting the car (assuming it has been left for a while) should be a smidgen over 12 volts. 14+ volts is the charging voltage of the alternator, so if you measure it after starting the engine and running for a while to charge back up it should reach 14v +.

 

Best way to check a battery is with a drop tester. This hits it with a measured load, and has a colour gauge to show battery condition.

 

 

 

Wha? The alternator won't be charging the battery at all unless the pulley gets up to sufficient RPM, i.e. when the engine is running.

 

If the engine can turnover quick enough it can get some charge into the battery - although optimal charge is when the engine is running. I suggested multimeter test as not every one has a drop tester and if its hitting 14 + volts at least you know you have a charge and the alternator is working.

[pcstru]

If the engine can turnover quick enough it can get some charge into the battery - although optimal charge is when the engine is running. I suggested multimeter test as not every one has a drop tester and if its hitting 14 + volts at least you know you have a charge and the alternator is working.

If you are turning the engine over with the battery and the battery is charging from turning the engine over, you had better be prepared to receive your Nobel prize.

[mac_shinobi]

That's not correct - the battery voltage before starting the car (assuming it has been left for a while) should be a smidgen over 12 volts. 14+ volts is the charging voltage of the alternator, so if you measure it after starting the engine and running for a while to charge back up it should reach 14v +.

 

Best way to check a battery is with a drop tester. This hits it with a measured load, and has a colour gauge to show battery condition.

 

 

 

Wha? The alternator won't be charging the battery at all unless the pulley gets up to sufficient RPM, i.e. when the engine is running.

 

I was under the impression it was the current so amps / watts etc that had to provide enough to start and crank the engine over not the voltage, generally at least 300 plus or more amps

 

Think my 1.6 petrol must need at least 400 or more ?

 

Just guessing regards to the amount of amps / current though

Edited February 4, 2015 by mac_shinobi

[3s-gtech]

As the charge drops, the voltage drops - the potential difference across the plates decreases. The battery has to provide a large current hit (CCA - cold cranking amps) when starting, but if it has been used and abused the voltage will drop. The battery is also made of several cells - these sometimes fail giving a cold reading of 10.8v or so across the terminals - new battery time!

[cpjitservices]

Lol maybe Im wrong then I thought if the engine was turning over fast enough you may be able to get enough charge to the battery if it has just dipped in charge. Maybe not.

[IrritableTech]

I was under the impression it was the current so amps / watts etc that had to provide enough to start and crank the engine over not the voltage

 

V=IR So if the current (I) drops, and the resistance ® of the circuit remains the same the voltage (V) will drop also. Ohms Law.

Edited February 4, 2015 by IrritableTech

[3s-gtech]

No, as @pcstru says - it would take some Physics bending for that to work. It may put a trickle of charge in, but not enough to make a noticeable difference.

[3s-gtech]

start the car whip the battery off whilst its running and connect old battery to the car and let the alternator charge it

 

Also - don't do this. Especially on a modern car!

 

Don't Disconnect the Battery with the Engine Running

[pcstru]

No, as @pcstru says - it would take some Physics bending for that to work. It may put a trickle of charge in, but not enough to make a noticeable difference.

It won't "put in" any charge. First, you can't charge a battery and draw power from it simultaneously (in terms of a circuit, you would simply be drawing less power). If you chopped the alternator out of the equation while trying to start the engine, you would then draw less power than with it in place. Which is basically saying that until the engine is running and the starter motor is no longer required, the alternator is an additional drain on the battery any way you look at it (and if you disconnect the alternator from the engine when it is running , you will use less petrol).

Edited February 4, 2015 by pcstru

[mac_shinobi]

 

V=IR So if the current (I) drops, and the resistance ® of the circuit remains the same the voltage (V) will drop also. Ohms Law.

 

Ah ok - that makes sense. So presumably you just test for Current and Voltage and if it is below 12 volts and how ever many amps then either needs to be charged or battery replaced depending on the age of the battery and if the cells hold enough charge etc

[pcstru]

Ah ok - that makes sense. So presumably you just test for Current and Voltage and if it is below 12 volts and how ever many amps then either needs to be charged or battery replaced depending on the age of the battery and if the cells hold enough charge etc

 

Basically ... sort of ... yes!

[woodham]

don't forget on a nice cold morning start your likely to drive with heater on window de mister on rear windscreen heater on, radio on, headlights on all this is extra load on a stressed battery that if your only doing 6 miles to work is drawing more charge out than it is getting back , take it for a good drive on the motorway just cruse at 50-60 ish at the weekend if safe to do so no headlights on , heater/demister off rear screen heater off radio off should put some charge back into it or just stick a battery charger on it