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SKID
21st February 2014, 10:27 AM
How to get more juice out of my alternator.
My problem is if I let my truck sit for a week or two, the battery drains. I have a lot of gadgets and accessories and an alarm running, I charged the batter to full about a week ago and took it for a night run with some mates, and after about 5 hours driving with the spotties etc on, my volt meter was running at about 8V, I could tell during the night that the battery was slowly discharging and that the alternator was'nt keeping up, By the end of the night unless my revs were right up, my HID's wold flicker and go out. Would putting a dual battery system in help? or what can I do to get the alternator to keep up. I don't want to have to take the alarm and accessories out of my truck if I can get away with it.

Any Advice or suggestions appreicated

threedogs
21st February 2014, 10:31 AM
how many watts are all your lights and what size alternator are you running ATM

Winnie
21st February 2014, 10:43 AM
Dual battery won't really help.... you need a bigger alternator. Cheaper than fitting a second battery too!

SKID
21st February 2014, 11:09 AM
How do I calculate the amount of watts? its a standard 50 amp alternator.

Winnie
21st February 2014, 11:16 AM
For example you said you had HIDs. Are they 55W? Higher? Lower? Just add them all together.

BigRAWesty
21st February 2014, 11:26 AM
For example you said you had HIDs. Are they 55W? Higher? Lower? Just add them all together.

Then once all added together, divide by 12 (12v system) = Amps.

I'm gunna take a stab and say your alternator is shot..
You can have them re kitted fir a little over $100

Or you can fit a bigger alternator

SKID
21st February 2014, 11:52 AM
I've just called a local parts wholsaler, I can get a 70Amp alternater which replaces my current 50 amp exactly via the part number, or I've seen some advertised on ebay for around the 200 dollar mark rated at 100AMPs. I know a new 50amp would mae a difference as this one is probably as old as my car "89 model" and a 70 amp wpould obviously make a difference as its pushing out an extra 20 Amps. Does anyone advise going to the 90-100amp models?

I've added up my lights and with out knowing what my alarm is pulling the lights alone add up to 30, not including my radio, my uhf and what the engine draws to run using the formular given above all added together, divide by 12 (12v system) = Amps.

BigRAWesty
21st February 2014, 12:25 PM
What motor and age of the car do you drive?

SKID
21st February 2014, 12:32 PM
What motor and age of the car do you drive?

Its an 89 GQ TB42S Carbie model

threedogs
21st February 2014, 12:39 PM
if you intend doing a lot of night driving I would fit a 100 amp alternator.
not fun stuck in the bush at night with a flat battery, the noises oh the noises lol.
As Winnie points out an AUX battery wont help your cause,
but if camping is part of your weekend then a second battery is great for running a fridge and camp lights

headlights are say 50/90 watt x 2 =100/180 watts
2 x say 55 watt HID driving lights = 110 watts
So we are nearly 300 watts divided by 12 = 25 amps
One of two things could be wrong either the battery cant hold its charge
or the Alternator is on the way out,
check the back of the alternator with a multi meter see what it reads at 1200 revs

SKID
21st February 2014, 12:51 PM
if you intend doing a lot of night driving I would fit a 100 amp alternator.
not fun stuck in the bush at night with a flat battery, the noises oh the noises lol.
As Winnie points out an AUX battery wont help your cause,
but if camping is part of your weekend then a second battery is great for running a fridge and camp lights

heaglights are say 50/90 watt x 2 =100/180 watts
2 x say 55 watt HID driving lights = 110 watts
So we are nearly 300 watts divided by 12 = 25 amps
One of two things could be wrong either the battery cant hold its charge
or the Alternator is on the way out,
check the back of the alternator with a multi meter see what it reads at 1200 revs


I wouldnt say a lot of night driving, out of all the 4wding I do less than 10% would be night time so could i get away with a 70AMP one, as every where that i have called can give me confirmation if it will just swap out with my current 50 amp one, except on place who has a 70 amp model and says its the replacement for the part number on my current one, when they compare that to their 100 AMP model the holes are different sizes and lengths are out etc...

threedogs
21st February 2014, 12:59 PM
take into account if you want to fit a winch at some stage down the track.
some times its just a matter of turning the end plates to match, but if they
say the 70 amp is a direct replacement go for it if the price suits your budget

lhurley
21st February 2014, 01:04 PM
A bigger alternator will help first up but a 2nd battery will help in the end. That way you can run your alarm etc off the 2nd battery and leave your main for running your car and headlights.

Winnie
21st February 2014, 01:12 PM
I wouldnt say a lot of night driving, out of all the 4wding I do less than 10% would be night time so could i get away with a 70AMP one, as every where that i have called can give me confirmation if it will just swap out with my current 50 amp one, except on place who has a 70 amp model and says its the replacement for the part number on my current one, when they compare that to their 100 AMP model the holes are different sizes and lengths are out etc...

Call Patrolapart mate... they have alternators over 100A on the shelf that are direct bolt up.
(03) 9735 9099

GQ TANK
21st February 2014, 04:13 PM
A replacement alternator wont fix your other problem - where you are leaving the truck for a week or 2 and the battery is going flat. Consider getting a tri state float battery charger that will maintain you battery while the truck is parked for long periods.

klompy
22nd February 2014, 05:13 AM
I would go as big as you can definately oner 100 amps.

SKID
24th February 2014, 11:00 AM
Wish I had tread this post last week, ended up bighting the bullet and buying a new 70amp one from Baxters, installed it on the week end and now at idle its sitting on 14 and a half volts, with EVERYTHING turned on it drops to just over 14 volts, So I think I can assume the old alternator was faulty as it wasnt doing squat at idle it would only start charging one I got over 1000RPM.

Thanks for every ones advice, will difinatly call Patrolapart next time.