For some strange reason my six volt battery is totally dead even after an overnight home charge. After replacing with a new one the amp meter is reading zero. Is my generator also dead because of this?
Can't help with your problem, William, but just to cheer you up, this Model A has a flat battery too.
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In fact almost everything is flat!
It sounds like your cutout was stuck closed and thus the battery would completely discharge through the generator because the battery would be trying to turn the generator as a motor. A bad cutout might then also no close its contacts when you run the motor and you would then not have any charge. DO NOT ignore this situation and do not run the motor without checking the cutout since running the motor and thus spinning the generator with no load on it (cutout contacts stuck open) will quickly damage your generator.
Bottom line - CHECK THE CUTOUT carefully.
A good battery gone stone dead and won't re-charge can very possibly be due to a short in the wiring system draining it as stated above. With a T, that doesn't have much wiring wise, a short or draw ( such as a closed gen cut-out) is easy to find. First: make sure lights & ignition are off. When connecting the batt. check for a spark as you make the connection. Use the Neg. terminal for this. It might be very slight but any spark would indicate a draw. (again, that closed relay). Disconnect the batt wire at the relay and look for a spark when re-connection the batt. If it's gone you've found your short or draw. Of course you've only located the problem, not fixed it. You could get away with just a new relay but the non-moving Amp. meter is troubling.
Do what Charlie said, but when you disconnect the wire at the cutout, be sure the end of the wire is not touching anything or better put some electrical tape on it. If that wire touches anything connected to the chassis, you will still get current flow and make your test invalid.
Norm
Thank you all. I found a new spare cutout in my stock of spares and fitted it. Bought a new six volt battery. Started engine and amp meter shows a positive charge. Very pleased indeed.
My next move is to purchase one of the new cutouts that is really a voltage regulator. I now appreciate the major problems that a faulty cut out can render on the entire electrical system. I don't want to be penny wise / pound foolish,
I think if the cutout got stuck it would have self destructed......I had that happen and I've bought John's solid state regulators to replace them.
Craig:
In fact the mechanical cutout if stuck closed will not self destruct since the generator presents something near to a 1 ohm load on the 6V battery and thus the discharge rate will be in the 6-10 amp range which is enough to quietly but efficiently completely drain and ruin your battery. If the cutout is stuck open then the generator will be running with no load on it and the battery will not be charged so you will be draining the battery out as you start the car or use any of the electrical things like lights. In this case the generator will be fried by the generator burning out its own field windings and the battery is ruined for lack of charge. Mechanical cutouts are really nasty and even if you don't buy my regulator - get at least a diode cutout from somebody and put it on since that way you only ruin the battery if the cutout shorts but diodes never fail open but always fail shorted so you can at least eliminate one thing from being ruined namely your generator.
John....the contact stuck on one of mine and it melted the contact arm slick and clean off.......luckily.......before the generator burned up.
John a curios statement and perhaps a context issue. We see diodes "fail open" but typically due to higher current than a Model T generator is capable of...I would say that we have done no testing or analysis of lower current diode failures or for that matter in the application we are talking about. I would acquiesce to your experience in this matter.
I would also suggest that lead acid batteries are fairly resilient. Not to say a deep discharge is a good thing but I'm not so sure I'm prepared to say it will ruin a battery.
Interesting observations and to that end an interesting conversation. I may have misunderstood why these things will happen but as I said maybe a context issue.
Re: stuck cutouts as posted by others, a 12v cutout that sticks can be a disaster. Many times a 6V generator can survive it but it is not a good thing nor would I take it for granted.
Often, if a 6V cutout fails closed, the generator will survive for a time. Sometimes, some damage is done and they will fail later. Sometimes they are fine.
In the service work I did for many years, we saw diodes fail, sometimes open, sometimes shorted. I never did try to figure which was most common.
We got involved in a fire alarm control panel controversy and saved a contractors business. The state wanted to shut him down because some panels he sold and maintained failed, creating a serious public safety hazard. Because the panels were certified and approved by both New York City and the State of California as well as Underwriter's Laboratories, it of course had to be the contractor's fault. My dad reverse engineered the circuits. Working back from where they burned, he determined that whether the unit simply failed or it tried to set the building on fire depended upon whether certain diodes failed open or shorted. Yes, one unit did set a building on fire. Fortunately, someone saw the smoke before the fire got out of hand. A couple other units did try to set their buildings on fire, but failed to do so.
Once my dad gave the state his evaluation of the circuit layout coupled with his power and temperature calculations, They dropped the investigation into the contractor. He was free and clear. And spent about two years replacing units at his cost to his good customers. That was just for good business practice. They were way out of warranty. I was the one that went to the UL local lab in Santa Clara to show and explain it to one of their engineers. That was about twenty years ago.
I did a lot of "bench repair", but never got his deep understanding of "sub-component level" electronics.
Drive carefully, and enjoy, W2