So you have a wet starter and AGM secondary?Quote:
Originally Posted by landoman
You really should use an AGM starter as well. LR changed over all D4 batteries to AGM for good reasons. The cars are hard on their batteries.
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So you have a wet starter and AGM secondary?Quote:
Originally Posted by landoman
You really should use an AGM starter as well. LR changed over all D4 batteries to AGM for good reasons. The cars are hard on their batteries.
Hi again sandman, and yes, you can use the AGM setting on most batteries.Quote:
Originally Posted by landoman
The only batteries that need an even lower setting are OLDER American GEL batteries, which there are now very few of them.
If you use the AGM setting on a wet cell ( flooded ) battery, the battery will simply take longer to fully charge, meaning the charger will be in the Bulk/Absorbtion stage for a longer period of time, before it goes into the Float stage.
With the intention being to rejuvenate the batteries, the amount of time each stage takes is irrelevant as it is the total time the charger is actually ON for that is important.
So just leave your charger in the AGM setting and all will be fine.
This might help in understanding sulphation. It helped me.Quote:
Originally Posted by landoman
Basically, if the battery does not receive enough regular charging agitation, maybe because it is only getting short stop-start trips or is sitting idle, sulphate crystals may form in the cells. Applying a multi-stage charger may reduce the sulphation, if it has not become permanent.
Sulfation and How to Prevent it - Battery University.
think of it as plaque on your teeth.
instead of using a pick to get it off you're using an electrochemical process, sometimes it works, sometimes it doesnt, even if it does work you can only do it so many times before the build up of crud in the bottom of the battery begins to short out the battery from the bottom or the material on the plate is too degraded to perfrom.
after 7 days of leaving the wet cell charging battery ( in the car ) on the ctek all night and the optima ( auxiliary .. out of car ) ) on all day I had both batteries tested to day by super cheap auto
The starter ( in car ) give the following results
BATTERY TEST
Rating 850 CCA
Measured 859 CCA
Volts 12.95
Good battery
STARTER TEST
normal
Volts 10.76
CHARGING TEST
OK
Volts 14.06
So can I conclude from this that my starter ( 8 months old ) is in ok shape
I now want to find why it’s loosing charge over 4 or 5 days
The optima was tested out of the car
Volts 12.83
Rating 765A EN
Measured 809A EN
I'd like to know what testing method was used....Quote:
Originally Posted by landoman
a battery that shows that many CCA but drops to 10.76V on a starter test means one of 2 things.
1. The CCA test was done out of vehicle with an electronic meter and it started out with a strong surface charge
2. the test was done in vehicle was done in car and used the starter motor to load up the battery for the starting test.
in which case....
I still think your starter battery may be on the way out. because....
If it was done in car using an electronic tester and the car started without cranking for a full 30 seconds (and 10 seconds feels like forever on a starter motor) then the battery is not going anywhere near its CCA rating if its dropping to 10.76V just starting an engine. The CCA rating is how many amps the battery can push for 30 seconds before the voltage dips to 7.2V
IIRC the starter for the tdv6 draws around 380Amps instantly on engagement then once cranking drops to around 220 amps and on average a warmed up tdv6 cranks for about a second to a second and a half before it starts...
if your battery was fully charged and in good health and it was able to push 850 amps for 30 seconds I'd expect the starting voltage to be nearer 11.5-12V.. By comparison my obtained second hand from a Cat 730 (blew the terminal off the bridge cable), Cat N70 class battery that I've had for nearly 4 years now still only drops to 11.5V (indicated on the cig lighter socket voltage gauge indicator that drives the USB/multi socket adaptor) cold starting a 4bd1 without glowing. Last time I tested it the instant amps was around 400 (the meter pegs at 400) and the while cranking amps averaged 250. To be fair I'm pretty sure the 4bd1 usually starts on the second or third compression stroke and doesnt need to wait for a bunch of computers to work out whats going on.
I suggest that you try doing a prolonged load bank test on the battery and test the RC of the battery. RC is how many minutes the battery can handle having 25 amps drawn from it before the terminal voltage hits 10.5V.
Fully charge the battery, let it sit for about an hour then put 25 amps worth of load on it (4 12v 75 w bulbs or 3 12v 100w bulbs) and measure it with a meter till it drops below 10.5
this time divided by the rated RC x100 gives you a better indication to the overall health of the battery.
I'd almost bet your battery is in the 70% bracket.
if its that or better then its time to start testing the parasitic load on the battery system of your vehicle. If I recall it correctly early on there were 2 fuses that you could pull that would drastically reduce the overnight drain on a battery and depending on which one (or both) you needed to pull to drop the parasitic load it indicated which systems were staying awake when they shouldnt be. one was the security system, the other was entertainment and I think the third was something to do with the vehicle dynamics (think suspension/traction control) 10 seconds on google show it to be FL17+18
D3 Battery Drain - Fuse FL17
DISCO3.CO.UK - View topic - Tracing a current drain.UPDATED 13/07/15,Fixed
fuse 26 and 28 also get a mention
Starter battery was tested by super cheap in car ...not sufficiently knowledgeable to understand how their testing machine works
What I do know is that the motor starts immediate and with out excessive turning over
...don’t know if the drop to 10.70
Volts is normal for a defender engine and battery (BTW I have a defender 110 I’m here on the D3D4 site as it’s here I found the most relevant thread .....( used to have a D4 )
I’ll do the load test suggested by Tim on the starter Battery using the ignition on ( not motor ) and headlights on and see what happens to the voltage
...find it hard to believe the starter is down to
50 or 70 % after 8 months
When I do the load test should I put the headlights on beam ?
I also have some led driving lights should I switch those on or just use the two headlights
Many thanks
Hi landoman, depending on use, you can drop up to 50% of a battery’s capacity in 3 months, so loosing a large amount of battery capacity over 8 months is not unexpected, again depending on usage.
The most common cause of rapid battery capacity lose is short drives and if combined with long periods of no driving, and you have the perfect receipt for a short battery life.
Given I constantly drive the car around Sydney
And have made a number of long drives ( to broken hill and Cooma ) every few months in the 8 months since I fitted the two new batteries
This would not seem to be reason my battery would be failing .... if indeed it is
I need to do the headlights draw test
.....so do I do high beam on or just the dipped headlights on
I also have two led headlights should I put them all as well or just do the headlights
I know to just put the ignition on and not have the motor running and measure the voltage before I start and continuously to see how fast it drops
Hi again landoman, you actually needed to do the load test before you started the rejuvenation charge cycles, so that at the end of the charge cycles, you could carry out the same test and then use the results from the first test as a reference point to see if the second test showed an improvement.Quote:
Originally Posted by landoman
Anyway, you only need to have your headlights on because the combination of the vehicle’s ignition load and the headlight load will be around 40 amps and this is sufficient to conduct the test.