I put an 8 volt battery in my speedster and I am wondering the best way to fully charge it. I tried a modern 6/12 volt charger and it ( the charger) got very hot with an over night charge. also I am not sure what the Model T generator thinks of the 8 volt battery but may be ok as I have a fun projects 8 volt reg installed on the gen.
So my main question is how to properLy charge the battery when not in the car. Thanks. Joe
Rule of thumb in our shop for charging an 8 volt battery is 2 amps for 2 hours will give you a full charge. Figured out by a freind who is an electronics engineer.
That is on 12 - 2 amp trickle charge. Works great for All 8 volt batteries we have used.
Over charging can warp the battery plates if done too quickily (Heat), aslo they can cystralize the lead matrix bound between the holder webs causing it to develop cracks therein. Most new modern day quality battery chargers have an additional electronic device incorporated therein, that along with the voltage charge, an additional mz frequency (about 10,000 cycles/sec) is introduced and carried ontop of the normal voltage, doing two things, totally changing the way in which the battery is actually charging, plus assisting the detector thermistor circuit in reducing the amperage by detecting the internal heat buildup within the battery/wiring over time (IE resistance), thus allowing for a reduction towards the end of the charging cycle and cycling into a more maintenance type charge untill taken off the charger. The Harbor Freight maintenance chargers are just this and that is all they do at very low amps, but at the proper charging voltage (approx 13.5/13.7 volts for a 12v battery), but the new Schumacker chargers for example are high oumph at the start, then backing down towards the cycle end with the more sofisicated electronic circuits therein, so as not to cook the battery so to speak. A longer/lower amp charge is much better than blasting the battery and making it get hot.
The generator itself doesn't care what voltage you use. It will work with 6, 8, 12, 24 or whatever. Just mind the maximum charge current and keep it below about 100 watts.
Has anyone ever had an 8 volt battery that was worth the powder to blow it up?
My brother ran an 8 volt on his '50 flathead V8. It cranked the motor better and made the lights brighter but didn't blow them out. We tweaked the voltage coil in the regulator (using a volt meter) to put out enough voltage to keep it charged. Don.
In my experience the 8 volt batteries I had had the longevity of a moth and less CCA than a GOOD 6 volt battery so....... <shrug>
I put an 8 volt battery in my Model T last year when the store was out of stock on 6 volt but had an 8 volt. I have been happy with the performance of the car with the battery change. A friend who is an electrical engineer made an adapter for me to make it possible to use my charger on the 12 volt range to charge the odd 8 volt battery. I also purchased a hydrometer to monitor acid specific gravity, to be sure I don't under-or-over charge it.
I've been banging in 12 volt trickle charge 3 to 4 times a year into an 8 volt battery for more than 4 years, it was in my 16 using no starter, now in a 26 and still working fine.
I built a capacitor + bridge charger that will charge any voltage battery at 1.6 amps. I have used it on 6,12 and 24 volt batteries for about 5 years now. The plans can be found on the net. I bought the components on ebay for cheap, about $30. PK
The only thing that 8 volt battery did to my T was break the Bendix spring.
A new 6 volt battery, a good set of rebuilt coils, and the proper 1/0 battery cables eliminated the hard starting problem.
James, it sounds like a 12 volt battery would have taken out the Bendix spring about 50% quicker. Lots of T people use 12 volt batteries. I hope they make a few changes to protect the starter from slamming in to hard.
Thanks for the various comments and inputs. I will try the 12volt @ 2amps for 2 hrs method next time I need to full charge. Joe
Assuming the 8V battery is typical automotive size then it is probably about 60-80 amp hour capacity. Charging it at 2 amps for 2 hours will put back 4 amp hours or less than 7% of its capacity if it is a 60 AH battery and only 5% if its an 80 AH battery. Hardly worth the effort and very likely to overheat your 12V charger unless it has a low current setting. Is your 8V battery periodically going dead on you? I guess I wonder why you feel you need to charge the 8V battery if your electrical system is working ok in your T. I have the same setup as you do except I am using 6V battery and 6V regulator. I have never yet put an external charger on my battery and it is rather old at more than 10 years. If your T runs on magneto then I would assume the only power taken from the battery typically is starting power or headlights for an occasional night drive. If you run the car during the day as the last thing you do and then shut it down - the battery should be fully charged at that point unless your charging system has something going on that is not right. I make the regulator you have so I am puzzled by your posting. Contact me offline if you need some help with it or clarification. I would be glad to help or explain.
I have an 8 volt battery in my car since 2008 and no generator. Keep it charged with a 6 volt standard charger which puts out 9.3 volts, no load. Ran the entire Canyonlands tour last week with many starts and lights. Down to about 8.1 volts and now ready for a recharge. A good value in my book.
John and others, thanks for your comments--I was just looking for some general info on best practice to fully charge an eight volt battery not in my car.
I do not have a problem with the battery going dead in my speedster. It does not have a mag set up on this car and it also is equipped with a distributed and has an eight volt regulator on the generator. I should not have mentioned the speedster as it is not Germaine to my question.
The reason I mentioned the speedster was it is a car that I don't use much and it had sat for sometime without use so I decided to charge the battery before my ride.
To clarify, what I tried was to attach a new Schumacker 6/12 volt charger to the eight volt battery ( not attached to the
speedster wiring) overnight and the charger was very warm in the morning.
So maybe a 2amp 12 volt attached to the charger for a longer period than 2 hrs would work and be safe? joe
Or maybe using a 6volt charger as Willard suggested would be a better option. Joe
This came up about a year ago. I'm confused... Why would you not just buy a proper 8 volt charger to charge your 8 volt battery?