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Sodo Thu Nov 01, 2018 8:27 am

jimf909 wrote: to diagnose the health of a battery (I'll let others chime in with corrections):
- Put it on a charger, bring it up to full charge let it sit for a day to see if it holds a charge of more than 12.7 volts
- load test it with the starter to see if voltage stays above 10 volts or so
- call AAA or take it to one of your local auto parts stores for a true load test to see what they have to say.

==============

Here's volt-meter test for lead-acid battery that's fairly easy.
Buying any used battery is risky, thus it should be cheap, so here's a way you might evaluate a cheap used battery.

Charge the battery (long enough to know it has reached its full charge) and then disconnect it from the charger. How can you know? Sorry you just have to "know" about the charger. A 10A charger for 4 hours should be a full charge on a Van battery. Check the battery voltage after it's been off the charger for 1 hour. It should still be above 12.65 volts.

Then let the battery sit (at rest) nothing going in or coming out for 12 hours. Disconnected is ideal for a real test. A good battery will show 12.65 volts 12 hours later. If it's below 12.6 its degraded. If below 12.4 it may still start the Van but has no real power capacity and you'll need a new battery soon. It's probably sulfated.

===============

A battery with 12.5v sitting .... will be at 12.4v soon enough. Don't pay more than $4 for a battery that has 12.5v sitting 12 hours.

Using simple battery "voltage of 12.6" is a very simplistic method and to employ it, you probably shouldn't share this information with the seller (or they can game it).

Any used battery that you buy, should have a minimum 12.6v. The seller could put it on the charger and then take it off an hour before you arrive - that's NOT a good reading (for the buyer). If the battery has 12.7v that means it was charged recently, maybe within the last hour and you[re being snaked. If seller puts it on the charger and truly takes it off a full day before you test it, that's better. To use the "12.6 rule, on an unknown battery, unknown seller etc, the battery must be sitting fully "at rest for 12 hours" and you have to try to suss that out.

Note that a new automotive battery can be reduced to $4 scrap by draining it to zero ONCE. (or two or 3 or 4 times ). But drained to zero even once, it has sustained damaged. A deep-cycle battery can handle deep-discharge much better.

epowell Thu Nov 01, 2018 9:26 am

Sodo wrote:

Here's volt-meter test for lead-acid battery that's fairly easy.
Buying any used battery is risky, thus it should be cheap, so here's a way you might evaluate a cheap used battery.

Charge the battery (long enough to know it has reached its full charge) and then disconnect it from the charger. How can you know? Sorry you just have to "know" about the charger. A 10A charger for 4 hours should be a full charge on a Van battery. Check the battery voltage after it's been off the charger for 1 hour. It should still be above 12.65 volts.

Then let the battery sit (at rest) nothing going in or coming out for 12 hours. Disconnected is ideal for a real test. A good battery will show 12.65 volts 12 hours later. If it's below 12.6 its degraded. If below 12.4 it may still start the Van but has no real power capacity and you'll need a new battery soon. It's probably sulfated.

===============

A battery with 12.5v sitting .... will be at 12.4v soon enough. Don't pay more than $4 for a battery that has 12.5v sitting 12 hours.

Using simple battery "voltage of 12.6" is a very simplistic method and to employ it, you probably shouldn't share this information with the seller (or they can game it).

Any used battery that you buy, should have a minimum 12.6v. The seller could put it on the charger and then take it off an hour before you arrive - that's NOT a good reading (for the buyer). If the battery has 12.7v that means it was charged recently, maybe within the last hour and you[re being snaked. If seller puts it on the charger and truly takes it off a full day before you test it, that's better. To use the "12.6 rule, on an unknown battery, unknown seller etc, the battery must be sitting fully "at rest for 12 hours" and you have to try to suss that out.

Note that a new automotive battery can be reduced to $4 scrap by draining it to zero ONCE. (or two or 3 or 4 times ). But drained to zero even once, it has sustained damaged. A deep-cycle battery can handle deep-discharge much better.

Enlightening!

Wildthings Thu Nov 01, 2018 12:25 pm

Even a pretty light load on a battery like a head light hooked up to it for a few minutes will take the surface charge off and thus give an idea of what the resting voltage is for the battery.

epowell Thu Nov 01, 2018 1:50 pm

OK... so i know my current battery is weak, but perhaps it is still strong enough to get me thru for a LITTLE while. When cranking it goes down to 10.4V. I charged it until full and let it sit for 12 hours, and the voltage is 12.84V... ...and it doesn't yet smell like sulfer when I crank heavily.

A topic for another thread, like this one (which I haven't read yet) https://www.thesamba.com/vw/forum/viewtopic.php?p=8539606
...but when I had that too tall strong battery for a day - it didn't do anything to help the start up issue....
I'm preoccupied at the moment with building another parking pad, but will get 'round to sussing out the glow plugs and relay etc ASAP.

Looks like my problem is not a dead or weak battery afterall....

?Waldo? Fri Nov 02, 2018 10:05 am

epowell wrote: OK... so i know my current battery is weak...

Why have you come to that conclusion?

epowell wrote: When cranking it goes down to 10.4V. I charged it until full and let it sit for 12 hours, and the voltage is 12.84V...

Those are strong numbers, not weak.

epowell Fri Nov 02, 2018 11:43 am

?Waldo? wrote: epowell wrote: OK... so i know my current battery is weak...

Why have you come to that conclusion?

epowell wrote: When cranking it goes down to 10.4V. I charged it until full and let it sit for 12 hours, and the voltage is 12.84V...

Those are strong numbers, not weak.

Hi Andrew...
....well I know that my battery is weaker than the TOO TALL battery I had for a day, because it bounces back much quicker than my battery. With my battery if you run plugs and crank, it leaves the voltage around 12.1 --- then it slowly slowly bounces back. With that too tall battery the plugs and cranking dropped it to about 12.4 then it bounced back faster and stronger.

Other than that my battery cranks and cranks no apparant problem.

BUT... probably the main reason why I concluded that the battery was dead was that after my 90min drive home from purchasing the van - (van ran great all the way home... stopped for fuel once... stalled once at a light > so I had 4 total start ups that day without undue cranking) ...but when I got home, I ran inside to grab my Mom to take a quick spin, and when I got back to the van and turned to KEY ON, there was NOTHING
...so I concluded that the alternator was not charging (because when the PO first started the van the battery showed on 12.6V with engine running so I concluded that the NEW ALTERNATOR was not charging. BUT... now the alternator shows 14V while running so it IS charging.
[the other thing is that the waterpump belt is VERY loose - but still turning things properly otherwise I would have overheated - and conversely the temp. guage was at 12o'clock all the way home... perfect cooling]

So I had figured the battery went dead and that is why nothing happened with KEY ON after the 90min. drive >>> but I now suspect that that is a different issue.

Perhaps the battery is still usable - but probably just on it's last legs. . .

?Waldo? Fri Nov 02, 2018 1:31 pm

epowell wrote: ...but when I got home, I ran inside to grab my Mom to take a quick spin, and when I got back to the van and turned to KEY ON, there was NOTHING

The fact that you went to crank and got nothing is not a solid indication that the battery is bad. The same symptom could be caused by a bad positive cable or ground cable or connection. If that symptom was caused by the battery, it is unlikely that the battery would ever recover and hold a charge. A battery that is completely dead like that will not typically charge back up and "show 12.84V after sitting for 12 hours".

The numbers you are quoting do not indicate to me a bad battery or even one that is 'on its last legs'. They sound to me like a decent battery and the problem is elsewhere.

danfromsyr Fri Nov 02, 2018 1:32 pm

this isn't the indication of a bad battery

I would get that from the HOT starter solenoid and poor electrical connections in the starter key circuit.

Quote: but when I got home, I ran inside to grab my Mom to take a quick spin, and when I got back to the van and turned to KEY ON, there was NOTHING

when a starter just clicks-cliccks-clicks-clicks... that's a dead battery.. enough voltage to fire up the solenoid, but not enough to whirr the larger starter motor.

I think your barking up the wrong energy tree on this one..

epowell Fri Nov 02, 2018 3:34 pm

Yes, thanks guys - I can see now that I totally mis-diagnosed the problem.

But the other thing that leads me to suspect the battery is weak, is that > to start, we know that the glow plugs are basically dead... and the PO has been *starting* the van just by cranking the HELL outta it until it starts. When I went to see the van the battery was at 12.2V... I charged it up full in 45min. @6A... then he started it up and it started immediately. So I assume that just before I arrived there he had started it up and ran it for some time to heat the chambers, but not long enough to charge the battery much.... hence he had most likely knocked so much out of the battery with who know how much cranking - and the result was a battery sitting at 12.2V which to my knowledge indicated a weak battery.

To be honest, I am more worried about my starter! :shock:

But yes for sure, I think the *blank battery* when hot is most likely due to corroded wires at the starter.... I had exactly the same thing happen with my Czech van. I haven't yet looked at the starter.... That's my next task after putting in the new Bosch Duraterms!

I'm just now finishing making the new parking pad. . . .

fxr Fri Nov 02, 2018 7:04 pm

epowell wrote:


I'm just now finishing making the new parking pad. . . .
Pictures are required!

jimf909 Fri Nov 02, 2018 7:48 pm

fxr wrote: epowell wrote:


I'm just now finishing making the new parking pad. . . .
Pictures are required!

Wha?

Without us all second guessing pitch, slope, materials, hours of sunlight reaching the van on the winter solstice, etc.

You learned well. :D

danfromsyr Fri Nov 02, 2018 7:54 pm

remove the starter, clean, sand, buff the mating surfaces
replace the negative cables, and clean,sand,buff the cable mating surfaces.

inspect the starter while it's out, replace if it is iffy.

me, i'd also install a 'hot start' relay, but some feel the wiring is good if it's good.. adding one more piece is one more piece to cause failure of course.

I like to remove the solenoid amperage from the ignition switch circuit.

I also like to add a ground cable directly from the battery to the starter mounting bolts.

jlrftype7 Fri Nov 02, 2018 8:14 pm

Buy a dirt cheap Carbon Pile or Resistance Element battery tester from Harbor Freight or other tool place and test your battery. Then you’ll know what you really have.

https://www.harborfreight.com/500-amp-carbon-pile-load-tester-91129.html

epowell Fri Nov 02, 2018 8:25 pm

Tomorrow I go to NAPA and buy my new DURATERMS (glow plugs) and install them, and hopefully start up nicely and just drive TONI into his nice new *spot* for the Winter to rest from all of this excitement. Thanks Dan for those tips, I will certainly do this things when I return - at very minimum if I get time now I will at least clean up the starter wiring > that's all I did on GEorge when he had that problem and he's been fine every since.

Yeah I have some pics of the new pad, but this one is very very basic (just gravel) and quickly done. . . nothing fancy. My Mom is an old Hippy and doesn't give a crap if things look "orthodox" > whereas in our Czech small town, everything has to be done so it looks like it was done by a professional... GF's Mom is the antithesis of an "old Hippy". Conservative to the extreme... ...but I'll post pics anyway. Tomorrow...

dobryan Sat Nov 03, 2018 7:23 am

When you go to NAPA ask them if they can load test your battery. Most places can do that. You'll likely need to bring your battery into the counter. The load test should give you a good indication of the state of the battery.

epowell Sat Nov 03, 2018 9:59 am

dobryan wrote: When you go to NAPA ask them if they can load test your battery. Most places can do that. You'll likely need to bring your battery into the counter. The load test should give you a good indication of the state of the battery.

OK, i'll just plop it into my back pack before I cycle the 5 miles down there :shock: :lol:

dobryan Sat Nov 03, 2018 10:47 am

epowell wrote: dobryan wrote: When you go to NAPA ask them if they can load test your battery. Most places can do that. You'll likely need to bring your battery into the counter. The load test should give you a good indication of the state of the battery.

OK, i'll just plop it into my back pack before I cycle the 5 miles down there :shock: :lol:

8) :lol: 8)

epowell Sat Nov 03, 2018 6:03 pm

New glow plugs in.... starting and running perfectly now... battery kicking ass > recharges full just by idling for 5 min.!
- - - all is well except for the parking pad (see new thread)

epowell Fri Sep 06, 2019 7:00 am

jimf909 wrote:
I know there are good battery maintainers that you can spend $200 or more on (search marine battery maintainer :D ) I've used versions of these Schumacher units on my vans and motorcycles for 20 years with good luck:

https://www.amazon.com/gp/aw/d/B07894CFCR/ref=yo_ii_img?ie=UTF8&psc=1

https://www.amazon.com/gp/aw/d/B0000AXTUY/ref=psdcmw_15707061_t1_B07894CFCR

Please tell me about battery maintainers... are they different things than CHARGERS? ....so with a maintainer I can leave it plugged in at my mom's house all year and battery will be perfect when I return? This is preferable to just having her plug it into a charger every 3 months?

epowell Mon Oct 14, 2019 2:29 am

I ended up finding on craiglist a SIDE TERMINAL battery - second hand but never even put in a car. $100... but 12 months old. Luckily this battery is in absolutely brand new working condition. I took a bit of a risk and luckily it worked out.



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