Car Battery Query

Pross

We've had a car sat on the drive without being used for a couple of months. Unsurprisingly the battery was completely dead when we went to start it so I put it on charge. When refitted it still would turn the engine over even with a jump so we bought a new battery. I fitted this tonight and it started first time albeit the first crank was a bit sluggish. I only let it run a few seconds as the belt was squealing but then when I tried again 5 minutes later it wouldn't turn over and sounded flat again. I've chucked it on charge overnight but surely, even if the alternator isn't working, it shouldn't run flat after starting the engine once? Anyone got a suggestion of what the problem might be? The only thing I can think is a dodgy connection / damaged cable but how can I check this?

ballysmate

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19748326#p19748326]Pross[/url] wrote:

We've had a car sat on the drive without being used for a couple of months. Unsurprisingly the battery was completely dead when we went to start it so I put it on charge. When refitted it still would turn the engine over even with a jump so we bought a new battery. I fitted this tonight and it started first time albeit the first crank was a bit sluggish. I only let it run a few seconds as the belt was squealing but then when I tried again 5 minutes later it wouldn't turn over and sounded flat again. I've chucked it on charge overnight but surely, even if the alternator isn't working, it shouldn't run flat after starting the engine once? Anyone got a suggestion of what the problem might be? The only thing I can think is a dodgy connection / damaged cable but how can I check this?

Son had similar problem with E46 BMW. Battery would lose charge and had to be jumped. Battery and alternator checked/changed. No different.
Bad earth strap was problem. There may be several around the car.

Pross

Cheers. Certainly sounds like a possibility. I just need to find where they are and see whether my ham fisted mechanical efforts are up to the task.

bbrap

Once you have sorted the connections/earth strap and got things going it might be worth investing in a Ctek or equivalent battery charger. These are chargers which are designed to be kept connected to cars which are used less frequently and maintain the batteries in good condition. Of course that depends on having the facility to leave it plugged in safely where it cannot be tampered with or stolen.

veronese68

New battery has probably been sat on a shelf for a while so won't have had a full charge. Hopefully it will be fine once fully charged. If not there is probably something else afoot.
Battery conditioner type charger like a Ctek is a good idea if the car is left for long periods. If there is a drain on the battery you could fit a cut off switch to isolate the battery whilst the car is standing. Any radio presets and the clock will die however.

Pross

Charged the battery overnight and cleaned the clamps with a toothbrush and baking soda but still no luck. Will check the earthing when I get a chance. Am I right in thinking that running a jump lead from the negative terminal to a clean piece of metal such as the gear box housing would show whether it is an earthing issue? We're trying to get the car sorted to sell on but only selling it for £150 so reluctant to do too much before it is better to just scrap it instead. Problem is it is my daughter's boyfriend's brother buying it and it's causing some grief as he is keen to have it and we can't get it started!

veronese68

If the earth strap from the engine to the body is no good that won't help. Run one jump lead from negative to the gearbox or engine. Then run another from the engine/gearbox to the body. A large nut or bolt attached to the body should do. If it starts ok it is an earth strap. Then try again with only one of the aforementioned jump leads to work out which one.

Pross

Cheers will give that a go.