Idling a vehicle to recharge battery?

Hi Willem,

They say the only dumb question is the one you don't ask so here goes. Why "after we have stopped and have set up camp" do you have to run the vehicle to top up the battery, hasn't the vehicle done this as you have been driving along.

I understand with the "when we are camped at a site for days" after driving my vehicle for 3 or 4 hours I can run my laptop and fridge fine for 2 days, without the need to idle my vehicle. All I have is a standard 70ahr cranking battery and 2 X 35ahr sealed batteries joined, the types used in Gophers etc.

Haven't had a problem yet, had a similar setup in the diesel also.

Hi Blaze

I try to stop at around 3.30-4pm every day when on the move.

Setting up, getting the fire going, cooking tea etc may take up to 3 hours. So around sunset I do this 'idling thing'

My laptop has had a crook battery for a while and I am buggered if I am going tp spend another $200 on a battery. I have had problems running the lappie off the inverter. So I run the laptop off the cig lighter socket via a Kerio connector. To get max volts I need to run the engine. So I charge the battery and do all my jobs at the same time.

This works for me. It is a bit of a routine I have gotten myself in to but it gives me peace of mind on the first day and days after that.

I have two Century 4WD Overlander 700CA batteries in line through an ordinary solenoid with dash switch.

Cheers

Makes sense to me now, even if you were using the inverter it would the bjeezus out of your batteries. As I said I do all the same things just luckily my lappie charges as we drive and I get about 2.5hrs working it before the inbuilt battery falls over.

Guess you will have to decide in the future with fuel costs, eg if you use 2 ltrs a week doing your system at an average of $1.40 per ltr = $280.00 per week on trips, Even if you get away as much as you do, LOL will take quite awhile to burn up the Battery cost. LOL

Msg me with your laptop make and model, I may have a second hand one hanging around...

Blaze

Maybe me but you mat have to re do your sums :-)

Gday Richard,

I thinks I was wooong, should have been about $2.80 per week. Geeeze, just an extra couple of zeros and a small move of the decimal place LOL

I reckon I used the same slide rule some members use when working out milage hehehehe

Hey Nick R..
Dumb question.. how do I test for the alrternater charging??? I havea milti meter is it right to assume that when the car is idling I put the multimeter onto the terminals of the Alternator and this well tell me how much output it's generating.. then as I up the RPM, so then should the alternator output??? Thanks for any advice. Cheers and Merry Christmas..

Coyote
I put the clamp meter around the positive battery lead, it will give you a net result of charge with all the accessories and stuff drawing as well. It is worth saying that not all clamp meters are created equal, there are heaps of AC ones around, it is only more recently that DC ones have become half reasonable in price.

Another way would to be to put it around one of the alternator wires that look like it may be the output, then rev the engine, I don't know for sure but you may need 15-25 amps to run accesories before any charging happens.
you may be able to tell something from the voltage, I'm not sure, I would imagine it would rise more slowly over the 1/2 hour or what ever, that is assuming that the charge is low, at the end of a day's drive I would expect batteries to be well charged...
I'm no auto leccy, this is some stuff I learned watching one was well as the sparky.
Merry Christmas,
Nick

Jeez Coyote, just checked your profile, with all that gear you'd draw a tonne of amps!!! if you used it all together that is.........

I remember we used to have 8 batteries in the back of the FFR's ;-)

I saw one of those go for a swim of the front of a heavy landing craft. They lowered the door as they approached the beach and the driver just took off over the front. Bump bump bump under the ship and the LR appeared upside down in the wake. The driver was OK but the radios weren't. It was put down to poor briefing.

Pete

Hi Willie,
Battery capacity might be 70Amphours for an N70 cranking battery.
Starter motor uses a heap of power for a very short time. So if you crank for 5 seconds, and it uses 200amps, you are using less than 1AmpHour.
If its a diesel, engine preheat varies, but may use say 60amphours for a minute which equals 1amphour.

So starting your vehicle uses bugger all power.

This is true, but as long as it's not too bad, next time you drive, just bury the loud pedal, and hold it there, heaps of manifold pressure and it should clear the glazing. always good to do this every now and then anyhow! just a thought!

this only happens (like wet stacking) when the engine runs below
operating temperature.. also in the US they start to outlaw excessive idle
because of pollution ... low idle is not healthy and does not charge anyway
unless you have a decent alternator (most jap cars don't) .. you need to
high idle and keep the temp up ... also you need to make sure your tranny
is up to it and pumps sufficient oil in idle .. Dodge does burn trannies in idle ..
Cummins is not recommending extensive idle .. I have no explicit info on
jap diesels .. Petrol engines are also bad to idle .. enriched air/petrol mix will
wash the cylinder walls and dilute oil ...
A diesel generator needs min revs to stay healthy ... high idle should be fine and
I assume that most trannies are ok too .. who drives a Dodge (rofl) ..
good luck
gmd

I think it's more the manifold pressure, and or load on the donk that will avoid glazing as apposed to the rpm.....

Queensland Police have their speed camera landcruisers idling all the time with the A/c running.