Was doing some bulb checking/chaniging yesterday which involved having the ignition on for a while. When I tried to start the car she wouldnt turn
over so stuck the (bike) battery on the optimate overnight but she still wont crank
without turning the key the battery is reading 12.2, with the fuel pump and dash on it is reading 11.5 but when I try to crank it quickly drops to
6.5.
is the battery dead or is there something else I can check ?
cheers
Sounds dead as a dodo mate.... Most batteries don't like deep discharging and bike batteries especially so. Although the optimate can do wonders I doubt it will resuscitate a completely dead battery...
all signs point to a dead'un.
optimate - that one of them piddly top up charger things?
put it on a proper big boy charger for a couple of hours.
if same, then it's time to release those pound notes lurking deep down in your wallet.
Where did you measure the voltage? Did you checK the earth and terminals?
A fraction of an ohm resistance will cause voltage to fall.
Darren
Some 'smart chargers' won't play with batteries under a certain voltage. Can you pop some jump leads on it and a running car for 10 minutes? Then see if it wants to play...
Sounds like it is a gonner --
I should have said the car did run yesterday before doing the bulb testing
was just in the garage and discovered that the wire on one of the optimate connectors was loose so have fixed that and put it on charge again to see
if that makes a difference
turbodisplay - all the measurements were done at the battery terminals - checked the earths and they seem fine as well
will update once the charging cycle is finished
Does it even attempt to turn over? Is it on carbs?
I have heard of a couple that have been left with the ignition switched on (and therefore fuel pump presurised) and they've slowly filled a
cylinder with fuel, via slightly worm float needles. Compression then locks them up.
Just a thought.
adrian
well, after recharging, she started first time, and 2nd time.....
3rd time I decided to just let the pump run for a few seconds and then turned her on but no joy - looks like (as most people predicted) a new battery
is required
It was the "quickly drops to 6.5v" bit that pointed to dead cell.
If you can fit a smallish car battery (such as a type 063 of a known brand ) it will stand a better chance of survival. How long a battery last
is a lot to do with how much charge you take out it between runs/charging.
With a motorcylcle battery its too easy to take quite a high percentage of the battery's charge out by by leaving the igniton or lights on even
for a short time.
The greater the percentage of charge you take out a battery the less charge the battery will hold when re-charged. To put it another way everytime
you use some of batteries chsarge it gets damaged slightly, the more you use the more damaged to the cells.
Any time you take a lot of charge out a battery it pays to stick it on a slow charge even for a short time before trying to start the car.
The other thing to be aware of is charging rate. In simple terms the slower the charge rate the longer a battery is likely to last, so if if you
take say 20% of a motorcylcle batteries charge out of it in a cold start and the car type alternator tries to pump its full 80 amps output into the
battery the plate will get damaged at an alarming rate.
When buying a good guide to quality is the length of warranty it is worth paying the extra few pounds or so for a battery with a 4 year or even 5
year warranty.
I can recommend http://www.tayna.co.uk as a very good internet supplier very quick delivery.
quote:
Originally posted by britishtrident
It was the "quickly drops to 6.5v" bit that pointed to dead cell.
If you can fit a smallish car battery (such as a type 063 of a known brand ) it will stand a better chance of survival. How long a battery last is a lot to do with how much charge you take out it between runs/charging.
With a motorcylcle battery its too easy to take quite a high percentage of the battery's charge out by by leaving the igniton or lights on even for a short time.
The greater the percentage of charge you take out a battery the less charge the battery will hold when re-charged. To put it another way everytime you use some of batteries chsarge it gets damaged slightly, the more you use the more damaged to the cells.
Any time you take a lot of charge out a battery it pays to stick it on a slow charge even for a short time before trying to start the car.
The other thing to be aware of is charging rate. In simple terms the slower the charge rate the longer a battery is likely to last, so if if you take say 20% of a motorcylcle batteries charge out of it in a cold start and the car type alternator tries to pump its full 80 amps output into the battery the plate will get damaged at an alarming rate.
When buying a good guide to quality is the length of warranty it is worth paying the extra few pounds or so for a battery with a 4 year or even 5 year warranty.
I can recommend http://www.tayna.co.uk as a very good internet supplier very quick delivery.
I have always found small motorbike batteries to last for a lot less time than a car one. They do not keep their charge for that long either. I always disconnected my battery from my bike and leave it on charge if left for longer periods.
I was given another tip on here for battery care.
If your working on the car and by chance have to remove the battery never ever store the battery on a bare concrete floor,always leave the battery on
the bench or at least raised from the concrete.
I also always leave the maintainance charge on the battery when leaving the car garaged for a length of time.