car not starting

[green123]

hello i have been having some trouble for some time everytime i go to the car it has a flat battery i think it could be something draning it i hooked up a new earth supply to see if it was that seems not so im unshure what it could be any ideas would be great

[chesney]

Check all wiring for a short somewhere. Try disconnecting the battery next time you turn it off, and reconnect it when you return.

[green123]

ive tried that and its slightly flatter when i come back to it so im shure the is a short somewhere but im not shure where

[bmcecosse]

If the battery is nicely charged when running - and you disconnect it when you switch off - and then it is 'flat' when you reconnect it - the battery is knackered...........

[green123]

yes i found that out took caps of to find a cell bone dry !!! so im going to take the battery back and then hopefully buy another whats the best battery to buy?

[bmcecosse]

Smallest battery they sell is fine for a Minor. Costco are good value batteries.

[green123]

where can i buy a battery from halfords seem a bit exspensive i bought my battery 7 months ago from a local car shop ,byut obvisoly batterys are crap so i myte try halfords

[chesney]

Local car shops can be a bit 'hit and miss'. My dad had a 6 volt one from a local shop, put it on a few months ago, and a cell has collapsed! At least with Halfords you do get a warranty, so you get what you pay for...

[bmcecosse]

7 months - I would be taking it back......you should have at least a year warranty......

[mike.perry]

I used to buy my batteries from Halfords with a 4 year warranty but they are getting too expensive.
Tried Costco, what a performance! Parked outside the service bay, had to walk round through the store and after signing in and finding the door to the back of the tyre and battery store I then had to attract the attention of a fitter, both of whom were in the service bay. I tried to explain what I wanted and suggested that I open the bonnet and show them, but I was not allowed through the service bay so I had to go back through the store. On the way I noticed that all the batteries were grey and I wanted black, so I gave up and drove home.
They had a discount on tyres so my wife decided that she (I) would replace the two worn tyres on the front, or back, can't remember which, on her Focus. They had a very limited selection and had some strange policy of only fitting the new tyres to the front (or rear) axle, needless to say it was the opposite end to the tyres which needed changing so all four tyres were swapped around, the fronts went on the back and the backs went on the front. It was irrelevent that the other tyres were nearly new anyway. And just as a passing shot, no they did not do tracking.

[bmcecosse]

Elf and Softy at it's very best! I just picked up a battery from the many many on the shelf and popped it in the trolley..... simples!

[green123]

went to the shop and they replaced it straight away 3 cells knackered so got a new one so hopefully all is good

[bmcecosse]

Well done -take care to connect it right way round - and in future check the acid level from time to time !

[green123]

yes im on negative earth as i put my alternator on an dworks good no igntion light on when i switch the engine off so all is good so hopefully no problems

[bmcecosse]

We ALL hope so.......fingers crossed.

[MarkyB]

3 cells knackered

That sounds like two too many, overcharging will kill batteries so I'd suggest you check what voltage you are getting with the engine running quite fast.
From memory, just over 14 volts is the maximum you should see, much more than that and the battery will overheat and get knackered in short order.

[bmcecosse]

It's just been converted from dynamo - you couldn't possibly have missed the thread Hopefully the 'new' alternator will have things under good control!

[green123]

hello i wen tover to the car it had a completely flat battery i have looked for things that could be shorting out i cant find anything ,if it was shorting wouldnt it blow the fusees . im not shure what to do now as i dont have a clue could any boy help me

[bmcecosse]

I suspect you have damaged the alternator by running it without the main feed connected - despite our best efforts to tell you how to connect it and to point you to a very clear diagram. If the diodes have been damaged it can still deliver a charge - but when stopped it drains current back. Can only suggest you charge up the battery - disconnect the alternator (both wires) - reconnect the battery and look for any sign of a tiny spark as you make the last connection. If no spark - leave the car overnight - is the battery still full?

[green123]

hello i went to the car with a fully charged battery disconnected the alternator and it started up but the problem was the igntion light went of should this happen? also it did sprak when i put the postive connection on cheers