before giving up on that battery, take it out of the truck and give it a good LONG, SLOW charge. a day or two. then try again. a couple hours just doesn't do it.
Ok, I have one charger that charges at 6amp and a smaller one that charges at 2 amp. Would a 2 amp longer charge be better than a 6 amp shorter charge . I am thinking at 6 amp, it wont stat on long ( auto shutoff after full charge I think)
I don't know the correct answer but I have always been told "long and slow"............I think it was about charging batteries also.
Depends on the charger, but 6 amps on a car battery is considered a "slow" charge. If the charger shuts off after a relatively short time, then the battery may be bad. If the battery is mostly discharged, and it has a reserve capacity of 160 minutes (25 amp discharge rate), you'll need to charge it all day at 6 amps to get it filled back up.
From the interweb thingy search... The time it takes to charge a battery = (Battery Capacity x Depth of discharge) / amp of the charger Time it takes to charge a battery is = (54 amp x 100%) / 6 amp The time it takes to charge a battery at 6 amps = 9 hrs. Let’s apply the formula using two more examples below: Example 1 - Change the amperage rating of the charger to 2 amp (slow charge) - Time to charge a battery at 2 amp = (54 x 100%)/2 - Time to charge a battery at 2 amp = 27 hrs. Example 2 - Amperage rating of the charger is 36 amp (fast charge) - Time to charge a battery at 36 amp = (54 x100%)/36 - Time to charge a battery at 36 amp = 1.5 hrs.
Get yourself an inexpensive hydrometer to test the state of charge of each cell (it may take longer than the times posted above, that's OK, let it keep charging till the hydrometer tells you it is fully charged). Once you get the battery fully charged, you need to put a good load on it to test it. If you don't have a load tester, most auto parts stores that sell batteries will test your battery for you if you take it in to them. It doesn't have to be their battery, they'll test any brand battery for you. It's a very simple test, easily performed in a few seconds. ETA, now that I think about it, most stores probably can't load test a 6 volt battery. You can load test it with the engine. Disable the ignition so it won't start and crank the engine for 10 seconds with the volt meter connected to the battery terminals, and watch the voltage level while under load. The volts should not fall below about 4.5 volts in a 6 volt system, and preferably will remain above 5. That will tell you about the strength of the battery.
Yeah, I thought 6 amp was slow but I thought even slower might be better being a charger has that option.
Thanks for these charts, wonder if they apply the same formula for a battery that 80% charged when you start charging vs one that is 50%
That 18.5, --18.5 reading seems to be a concern. What is the meter? What scale was it on? Digital wasn't around when that truck was made, and as mentioned there are times when you can't beat a quality ****og (needle) meter. A shop manual from then would show using ****og. Digital may be picking up/trying to read noise like inductive coupling from ignition, etc. To me it depends on if you want to keep it stock or make the 12v conversion. You can get a 6 volt alternator, replacing the generator and regulator. Sent from my SM-S320VL using Tapatalk
Long and slow for charging is the best way to bring a battery back up. With industrial forklift batteries that generally take 160 amps an hour to charge in 6-8 hours with a 6-8 hour cool down before using. We have a forming charger at the shop that we do either a 24 or 48 hour 30 amp slow charge on and in most cases as long as the battery isn’t old or really beat up we can bring it back to a serviceable charge. Try the 2amp charger for a day or two And that battery should be reading closer to 7 volts fully charged A 6 volt battery reading 6 volts is dead Anything under 6 volts static is junk Under load should not drop more then 4.5 volts or so 6 volt batteries are no longer popular and can sit and get sulphated This can be cured (kind of) by discarding the battery and then doing a high amp charge for a short time ( put it on engine boost and leave it for an hour) Then discharge it again and do your trickle charge. Something else to look at is, is the battery in the truck an automotive battery or industrial? As a 6volt industrial battery is not the same as a car battery Has a larger reserve but no cranking amps. A cheap alternative is going to an 8volt battery as you swap the battery and tweak the regulator and everything else stays the same You get much better starting power. A six volt system might get you 4-5 starts with out charging the battery in between.
Being it is a '39 truck; is it possible that the "regulator" (since it is mounted on the generator) is really a cut-out, and you have a three brush generator? Maybe put a good ammeter in the system and adjust the third brush for a proper charge rate before you condemn the battery.
I'm thinking going 12 on the whole system . I had been thinking of changing the ign to electronic and was advised that a 6 volt electronic ign is more problematic than a 12 volt so I had my mind on this anyway. Have a good gen/ alt/ started repair place in town that I talked to today and said he could convert the gen to 12 volt and set me up the correct regulator as well. I prices everything on speedway just to be prepared and everything looks like $750.0oish minus the battery. That would be a 12 volt gen with a reg , Mallory 12 volt electronic dist, flame thrower coil,spark plug wires, ballast ( not sure but I think I need on the ign switch) and a 12 volt starter solenoid. I can get the other stuff locally, bulbs 12 volt reducers or whatever I need.
First make sure the battery is fully charged, and will hold a charge. Then check the generator charging current/voltage, to make sure it's within specs. Swapping everything over to 12v should not be necessary, but it might (or might not) solve whatever problem you have, that you haven't yet identified....without having to even identify the problem!
When my '53 PU sits for a while , if I don't squirt gas in the carb I have to crank a long time before it fires. It cranks no problem. More than 3-4 starts. 6v batt, original alt. Also my 2 tractors are 6v and they crank fine, even when the Ford loads up.
had that same issue with a 41 Cadillac got a 6 volt fuel pump and solved the problem . Cost around 40 bucks
Modern gasoline is a ***** with old cars....it evaporates way too quickly. that in itself might be a good excuse to switch to 12v electrics, although as you said you can add an electric pump to help out.
The windings in the reverse current cut out only know if current is flowing not which direction when the voltage from the generator is more than the battery the points close. As the output from the generator drops and the flow goes to zero the points open. If they stick a little and the flow go the other way they will remain closed and stuff starts smoking.
Well after a not so good week with the batteries and so forth I gotta say I had the best luck today. I called on ole friend who has been working in a 39 coupe for a long time. Things have happened and he is selling car. He asked me if I was interested and although a 39 and 40 coupe are probably my favorite cars I said I had enough to work on now. Anyway I told him what was going on and he said " well my car is stock and has a running engine and I bought alternator and a Mallory electronic ign and I could sell it to you and sell my car as is" So I got excited and said I had priced the Mallory and was thinking about getting my gen converted to 12 volt and asked what he would take . He said , well I have 600 or so in it and I would let you have it for 450.00 I jumped on it . I get the Mallory ign, a flame Thrower coil , plug wires and the gen( he said it was a power something . I googles it and power master makes alt that looks like a gen. Oh I get a starter solenoid as well. I will pick it up tomorrow.
Quite a deal. When changing to 12 volts be sure to unhook your lights and 6 volt gauges beforehand. It’ll burn all of them up. You will need to add a resistor/ resistors. Your old starter and solenoid will operate fine with 12 volts.
Got the truck converted to 12 volt.Can barely hold the started ****on down to start. Mallory dist is really nice , works well.
So, to recap, you let a Generator kick your ***. Barely above stone knives and bearskin. Got it. (kidding!)
I was told to charge the battery at the rate at which it was discharged. If it was run down cranking, that is fast, charge it at a higher rate. If it was a parasitic or unknown drain, charge it slower. But it still should only take a full day to charge it back up. A hydrometer is a good diagnostic tool and will isolate a dead cell quickly.
One thought. I would pack everything away in a box so it's there if you or someone else ever wants to put it back 6 volts. Sent from my SM-S320VL using Tapatalk
The Jalopy Journal
