I have a 1950 ford, 6V system usually keep trickle charger if not planning to drive for a few days. After a ride today. Battery was 6.4 V with key off. 6.1V with headlights on (still key off). Mechanic looked at Overdrive for me couple weeks ago said was malfunctioning till he charged battery.
If the battery is more than a few years old, it's probably time for a new one. But it's pretty hard for us to tell, because we're too far away to load test it.
Batteries (usually) have a reliable life of around 3 to 4 years, depending on the quality (aka cost) when new. If you need a new one, it would be the time to have the charging system checked out. 4TTRUK
A fully charged, good condition 6v battery should be 6.3-6.4 volts. Turning on the lights without the car running will drop it as you saw. If it is lower than that while you are driving, have the charging system checked out. If it is draining excessively when it is not on the trickle charger, look for the source of the drain and repair that. Not sure it sounds like there is anything wrong with our battery. Possibly there is an issue with your overdrive unit. Maybe the solenoid is gunked up and requiring more voltage than it should to operate.
Thanks, good suggestion about the solenoid. Car has started fine after sitting couple of weeks with no charger so I don't think there is a big drain. As expected it takes the generator a while to re charge it. Ammeter shows charging while driving even with lights and electric fuel pump on.
I drive my 61 Dodge about 300 - 400 miles a year. I'm sure sometimes it might sit for 6 months without being started. it always has juice and starts without any help, my last battery lasted 8 years. I have never put it on a trickle charger. I never unhook the cables. so I would say if your battery is being drained from sitting you have some sort of short somehwere that needs to be fixed, or perhaps your battery is weak.
I have a 50 Ford, flathead and still 6 volt. I have always run Advance Auto Parts batterys. I have gotten as many as 5 years out of one. Never use trickle charger, never unhook cables. It always starts even after setting for a few months. I have put 80k miles on it from 1995 to about 4 years ago. Haven't driven it much in past 4 years because charging system is not working. If I want to drive it I charge the battery. I am thinking about going to 12 volts but with all my other projects, I haven't had time to mess with it and I can drive my other cars. That's the problem with having too many cars/projects. Need to get on it because it doesn't do them any good sitting! Like someone else said "get a new mechanic". Ron
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