It seems my generator is putting out 10 volts. I have wired the cutout directly to the positive post of the battery and added an extra ground from the battery directly to a head bolt. Still getting 10 volts. Even though the battery holds a charge and cranks the engine well. Is it toast? I have always thought the battery was a resistor of sorts that basically held the generator to no more than maybe 7 volts. All of this baffling me.
The generator charges the battery by having a differential of voltage. If the voltage is higher at the generator it charges the batterry.
The greater the difference in voltage, the higher the amperage.
You should get one of John Regan's voltage regulators.
Where are you measuring the 10 volts at for all of these measurements? Are you using a digital meter? If you have 10V at the generator - do you also have 10V across the 6V battery measured from battery post to battery post?
John, I measured used an analog dc voltmeter. I measured voltage from the cutout terminal to ground and from the generator output post to ground. There was just a slight drop across the cutout. Also, I ran a jumper from the cutout to the positive post of the battery to eliminate the wiring. Still had 10 volts as before. To me, it's the battery itself, but tomorrow I'll check from post to post.
I have used the regulators before, and I will get another one. No offense, but what did they do in the past if the car was burning out light bulbs and had a higher voltage output on the generator. In other words if the car's wiring is nice and tight, what would cause the generator's output to increase? It has to be the battery, doesn't it?
How many volts does the battery measure with the terminals off? Have you checked the cells with a battery hydrometer?
What is the AMP output at the generator?
Maybe the nut holding the adjustable brush is loose or not holding.
At the approx. engine speed of 20 MPH the generator output should be around 4 to 6 AMP's.
If the battery has a high internal resistance then the voltage will climb up higher than normal. If you have the generator 3rd brush set very high (greater than 5 amps or so) and are using a cutout then you will be overcharging the battery and it will have short life due to the constant overcharge. During the T era a one hour ride would rarely include more than about 10 minutes at speeds exceeding 20 MPH thus a 10 amp generator setting would result in about 3 amps total average charge for the 1 hour ride. Today if you went for a 1 hour ride less than 10 minutes would be spent at speeds less than 30 MPH and your 1 hour ride would result in very close to 10 amps total average charge. Thus you have 3 times the charge rate with the exact same generator setting because the roads are so different today. Modern roads made the Voltage Regulator very necessary if you don't want to have to change the generator setting when you drive at night.
I suspect you may have a bad battery and possibly a very high charge rate too which will be ready to wreck a new battery if one is installed and the battery charge rate is not reduced.
I have 10 volts across the battery posts at a fast idle. Will try a different battery tomorrow. Charging at 2-3 amps now. Will get a regulator in the spring.
If it is charging at 2-3 amps with 10 volts across the battery you really don't want to put a good battery in there to ruin. Reduce the charge rate to near zero before installing the different battery and then only bring it up a small amount so that even at a charge voltage of 7V you still only have 2-3 amps. If the charge rate will NOT reduce then have the generator checked out by a competent rebuilder which rarely includes a local modern shop. I guess what I am saying is make sure that the generator will reduce the charge when you move the 3rd brush and check that adjustment through its entire range before you put on a VR since a VR will not cure a sick generator which may be part of the problem. The correct adjustment of the 3rd brush will generally produce 1 Amp with the lights on at high RPM when the 3rd brush is set about half way in the allowable mechanical range. You need a good battery, good wiring including a reasonably accurate ammeter, good generator and a good voltage regulator all on the car at the same time. Piecing it together one piece at a time can result in a lot of damaged components until you get all good parts in place. When all is good and adjustment of 3rd brush is set correctly you are good to go for a very long time. I haven't touched my generator/VR since it was installed in the late 1980's and in fact that car has the first prototype VR still on it and working fine.
A 6 volt generator will put out much greater than 6 volts I have a 50s 6 volt that puts out 20 volts @ amps 50. Your 10 volts would seem normal for a "T" genny so you have regulator or battery issues. If you have the engine running at fast idle and remove the battery the voltage to the system will increase and possibly burn out light bulbs. I have started a vehicle with a dead battery and didn't have jumpers and installed a good battery in the failed vehicle brought the idle up and switched batteries. With the battery out of the vehicle and running on the generator the headlights were extremely white just to the point of burning out. I would say you have battery or regulator issues. The generator appears to be functioning proper.
This is an adjustable 3rd brush type generator. It doesn't work the same as your example generator. The 50's generators were all equipped with a voltage regulator to hold the voltage down to "normal" range while an adjustable 3rd brush type used from 1919-1939 was different in that it did not come standard equipped with a Voltage Regulator that was external to the generator. The 3rd brush was a device that limited the current output to whatever the 3rd brush was set to deliver and it limited the current - not the voltage. The generator's that had voltage regulators always used with them were of the 2 brush type and can be identified most easily by having not only the usual armature connection but also they have an F terminal for an external Field connection.
I don't know anything about said third brush generators so this jogged my curiosity and I dug into my 1926 Dykes Encyclopedia and there is a lot of heavy reading on the subject. It discusses a relay/regulator with coils and points in side and the points are current actuated at high speeds the points close and as the speed lessens the points open WHAT IF THE POINTS STAYED CLOSED AT LOWER SPEEDS? A paragraph in the book states "Therefore, the charging circuit must not be opened by removal of the battery or open circuits, otherwise the generator would build up a high value" You say the battery holds a charge and cranks the engine well so that would eliminate the open battery issue. It appears by the drawings that the generator is internally grounded perhaps you might want to confirm the generator housing is grounded. It seems that the generator is putting out and the battery circuit is closed therefore the only remaining issues are the generator ground or an issue with the relay/cutout. Best of luck