Battery holding charge issue....

Dervis Garip

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Guys recently after not driving the 80 for 4 days the batteries seemed dead, Very hard to start the vehicle so wanted to share and get some thoughts and more experienced opinions from you all.

Background setup:-
Two 95 amp batteries recently changed upfront ( larger than standard than 75amp?)
one 100 amp battery at the rear for accessories like USBs but mainly the Engel fridge used in summers only tied to a relay to which upon startup all three batteries engage and charge from the 80 amp standard alternator and isolate from front to back upon ignition off.

The alternator was repaired twice last year once with the voltage regulator when the dash light came on and then on another time, the rectifier diode packed up.

My questions are am I expecting too much for the 80 amp alternator to deliver long term reliability?

Thank you kindly
 

Mick W

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Looks on the surface that your Alternator needs upgrading as an 80A one isn't going to be sufficient for all three batteries. Do you have a solar panel to supplement the charge? Sure there will be some more accurate explanations from the members soon.
 

Firewout

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I also thought that my batteries were dead last week. A lot of clicking relays but the startermotor didn't engage and the voltage gauge went to zero.
Tested batteries, switchover relay, starter motor etc.
When I tested the batteries with engaging the winch, one seemed fine, but when I disconnected one battery, the winch didn't move.
At last I found that the connection on the + pole with the 8mm bolt sparked when I tried the winch.
Conclusion : burnt contacts.
Solution : cleaned all the connections with 150 grit sand paper and all is well again.

Conclusion 2 : before changing batteries or alternator, check the connections.
Hope this helps,
Grtz
Wout
 

Chris

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I think people underestimate what 80 amps looks like. It's a lot. Because I have a couple of the Victorn systems, (OK 3 of them), I can see what a battery is getting when it's charging. My leisure batteries, when run fairly low typically get around 7 to 10 amps when I fire up. Once, I saw 20 odd amps for a while, but I think if you were to try to force much more than that in, they'd probably explode! If you have a current draw of 20 amps and an 80 amp alternator, then swap it for a 120 amp alternator, guess what current draw you get - yes, 20 amps. If I were pumping out 120 amps into the loom I think something would catch fire. I'd also be wondering where all of that was going. Two batteries is as nature intended and they fitted an 80 amp generator. I don't think that adding another battery equates to needing 120 amps.

No way are the batteries getting 40 amps each. Nope. I agree that there is something else wrong here. If the batteries are charged fully when you park and flat-ish when you return, it's not because the alternator isn't big enough, eh?

Same with my CTEK systems. I put the DS and Smartpass in to give me 120 amp capacity. Never seen that Ever. My Hilux has DC2DC charger and it's a 25 amp unit. Never seen more than half that as an output.
 
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Dervis Garip

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Looks on the surface that your Alternator needs upgrading as an 80A one isn't going to be sufficient for all three batteries. Do you have a solar panel to supplement the charge? Sure there will be some more accurate explanations from the members soon.
Hi Mark no solar just a basic setup that suits my needs as it is.
Looks on the surface that your Alternator needs upgrading as an 80A one isn't going to be sufficient for all three batteries. Do you have a solar panel to supplement the charge? Sure there will be some more accurate explanations from the members soon.
Hi Mark no solar just the system described for two years running. First time having issues like this.
 

Dervis Garip

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I also thought that my batteries were dead last week. A lot of clicking relays but the startermotor didn't engage and the voltage gauge went to zero.
Tested batteries, switchover relay, starter motor etc.
When I tested the batteries with engaging the winch, one seemed fine, but when I disconnected one battery, the winch didn't move.
At last I found that the connection on the + pole with the 8mm bolt sparked when I tried the winch.
Conclusion : burnt contacts.
Solution : cleaned all the connections with 150 grit sand paper and all is well again.

Conclusion 2 : before changing batteries or alternator, check the connections.
Hope this helps,
Grtz
Wout
Just to add batteries have been trickle charged twice, once with me at home and also at the auto electricians. Also tested by them and told there's a weak charge on load. Nothing drawing power otherwise tested. Also in the dash sometimes the charge looks higher as normal. Most times not being the times tested by the auto electricians as always the way.

I leaning towards the alternator being part faulty charging sometimes better than other times. Won't know until its take-off.

Thanks
 

Dervis Garip

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I think people underestimate what 80 amps looks like. It's a lot. Because I have a couple of the Victorn systems, (OK 3 of them), I can see what a battery is getting when it's charging. My leisure batteries, when run fairly low typically get around 7 to 10 amps when I fire up. Once, I saw 20 odd amps for a while, but I think if you were to try to force much more than that in, they'd probably explode! If you have a current draw of 20 amps and an 80 amp alternator, then swap it for a 120 amp alternator, guess what current draw you get - yes, 20 amps. If I were pumping out 120 amps into the loom I think something would catch fire. I'd also be wondering where all of that was going. Two batteries is as nature intended and they fitted an 80 amp generator. I don't think that adding another battery equates to needing 120 amps.

No way are the batteries getting 40 amps each. Nope. I agree that there is something else wrong here. If the batteries are charged fully when you park and flat-ish when you return, it's not because the alternator isn't big enough, eh?

Same with my CTEK systems. I put the DS and Smartpass in to give me 120 amp capacity. Never seen that Ever. My Hilux has DC2DC charger and it's a 25 amp unit. Never seen more than half that as an output.
Chris did not have these types of issues in the two years running this system. I thinking along the same lines as you have worked well up to now. Considering my power draw is minimal even with 3 batteries. Not running winches, big lights, inverter, etc. More like led lights all round lol. Perhaps less draw than normal. I guess I'll get it out to see what comes up.

Thanks
 

Towpack

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I also have a third battery in the back (95ah) and the standard alternator copes with all three, no problem. I was getting low output (13v) from the alternator a while back which improved to 14+ after cleaning the connectors on the back, the plug was particularly manky although I had no lights misbehaving on the dash. I've had, in the past, a drain problem from the intake heater relay which was pulling 300+ma and killing the batteries over a few days parked up. Draw should be 40-50ma with the alarm set.
 

nick_the_fish

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the batteries seemed dead
Dervis, when you say the batteries were dead do you mean all 3 were dead? That'd be weird.

Firstly I would find out what the alternator is putting out at 1000 RPM. Should be 14.2v - 14.5v. Then take the truck out for a 20 min drive which should be enough to get all batteries charged. When you stop, give it a minute or two for the excess charge to come off and see what they're holding. Are they at 12v? Then give it 12 hours and check them again. Still at 12v. Give it another 12 hours and repeat ......

Should give you a starting point as to whether the batteries are getting charged, and which one is discharging. Oh and as said above clean your contacts before you start.
 
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Dervis Garip

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Dervis, when you say the batteries were dead do you mean all 3 were dead? That'd be weird.

Firstly I would find out what the alternator is putting out at 1000 RPM. Should be 14.2v - 14.5v. Then take the truck out for a 20 min drive which should be enough to get all batteries charged. When you stop, give it a minute or two for the excess charge to come off and see what they're holding. Are they at 12v? Then give it 12 hours and check them again. Still at 12v. Give it another 12 hours and repeat ......

Should give you a starting point as to whether the batteries are getting charged, and which one is discharging. Oh and as said above clean your contacts before you start.
Nick to clarify the front two were very low I'm guessing because the vehicle starts usually effortlessly. Upon a shock and second attempt, the third leisure battery managed to help start the vehicle based on my setup. Contacts are clean inspected at the auto electricians. Leisure battery hasn't been tested tbh as its reading close to 13 amps when parked up and 12.5 amps overnight with the fridge running. I'm learning towards the alternator being the issue so hopefully will know sooner than later.

This has been an issue for the last few weeks and in that time driven much in it even after trickle charging the front batteries twice.

Thanks
 

goodoldboy

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Measuring V is a crude way of determining battery health but as starter batteries are sealed it's all we've got.As Chris said 80A is a big charge - 1500 W of 12V solar panels will give about 75 AH .Doing the basic first aid as mentioned in other posts is a good start but if those batteries have fallen below 10.5 at any time their capacity will have been permanently damaged. Your auto sparky should have a way of testing the alternator under load ?
 
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frank rabbets

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How old are the batteries. Several brands on mine only last 3 years.
The plug on the alternator might need stripping and reconditioning.
Frank
 

flint

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A cheap battery drop tester is handy to have. A couple of times in the past I've had new batteries give problems after a month or so with internal problems (faulty/weak plate links).
 

Towpack

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I replaced my batteries last year, for the second time, with two exactly the same. The originals lasted 9 years, the first replacements less than half that despite the originals being flattened to below 9 volts a couple of times so excessive draining of batteries doesn't necessarily damage them but you can get good and bad batteries from new.
Check the voltage at the battery terminals with the engine running at fast idle and all electrical equipment turned on. Assuming all wiring and connections are sound the voltage shouldn't drop below 13v minimum. If it does, the alternator is either failing or it's not big enough for the vehicle's needs.
 

frank rabbets

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I understand the alternator size should compare with the average current taken out. Batteries are the reservoir and are topped up by the alternator so this needs to equate to what is being drawn off. If one has a huge flat battery this will not damage a "small" alternator.

T.P. I've only had big lifespan on batteries fitted on new cars. What brand battery gave you the 9 years? I had Varta last time.
 
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Towpack

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The LC had Varta's fitted when I bought it. No idea how old they were but even if they were new, 9 years is very good going.

Dropping below 10.5 V will lessen the amount of charge they can hold.

When mine got drained (twice) with the relay problem I had them tested at a local battery supplier after fully charging them, thinking they were on their way out and one was at 95+%, the other 92% of their rated capacity so, bearing in mind they were a few years old at this point, draining them did them no harm IMO. The quality of the battery to start with has a much greater influence on it's life.
 

goodoldboy

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Yeah I had Vartas & replaced them with Bosch silver that looked identical.They lasted 3 years....it's not quality per se but build spec.Starting batteries have thinner plates & can supply cranking Amps & deep cycle ones have thicker plates.My solar P.V.batteries are Trojans who claim 5000 cycles to 50% DoD.we'll see..my understanding of heavily discharged batteries is that plate thickness is important but bellow 10.5 changes in the chemistry take place.the same Trojans with a 80% depth of discharge will only last 2000 cycles (IIRC)
 

Towpack

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My reference to quality was not regarding one make over another, rather why can two identical batteries, subjected to the same use on the same vehicle have such a difference in lifespan. Given quality control should be the same for both could it be put down to slight differences in the quality/purity of materials or that one was assembled slightly "better" than the other. It's a bit like buying a car and having no end of trouble with it from day 1 and the bloke down the road buys the same one and runs it into the ground with no issues whatsoever.
 
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goodoldboy

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Once batteries became sealed the life span fell off a cliff.Even gel batteries will dry out over time.Call me a cynic but vigorous lobbying by the big battery manufactures brought in sealed as a so called solution to folks dumping used batteries & acid leaking out.What a load of bollocks.
 
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