Cub charging problem

OLDFORDS

New User
Hello, I have an all original 57 Cub, recently I replaced the 6 volt battery and when I started her I noticed the voltmeter needle moved to the left, when I put a volt meter on the battery it read 11.5 volts, I assume the voltage regulator has gone bad? The battery is disconnected from the tractor but it now still reads 11.5 volts, it's a sealed 6 volt battery I got from NAPA, can I assume the battery is fried as well?
Thanks, OLDFORDS
 
There is no way a 6v battery can produce more than about 6.4 volts on a best brand new day. It is likely a 12v battery discharged to 11 volts. Count the cells in the battery if 6, it is a 12v battery each cell produces 2.1 volts. Jim
 
Ya I have to sort of agree with you. 6 volt battery reading 11 volt I do not think so but I have had 12 volt batteries read 14 volts. Had one the other day that I had just taken off the charger and it read 14.? volts
 
Well I put a different 6 volt battery in (read 6.4 volts) started the tractor, diconnected the battery and was reading 9.8 volts on the cable ends with the tractor running, I'm assuming the voltage regulator is bad and I'm going to replace it. The 6 volt battery that was in the tractor sitting on the ground reads 11.8 volts. I guess I'm lucky it didn't explode and I'll get a new one.
Thanks.
 
Taking a battery cable off the check to se if it is charging is a good way to let the smoke out of things. One should NEVER do that as a test to see if the system is charging. If that is done with and alternator one can get a very nasty shock and even worse it can kill out if you go hook up between ground and the + cable while running.
In your case if it is a solid state VR your very likely to have let the smoke out of it the moment you unhooked the battery
 
There is no way (as old points out) to test the system by disconnection. The battery is not only a load, it is a definition of voltage for the charging system. Hook it up, run it and test the voltage from bat post Positive to bat post negative. 7.2 + one volt or - half a volt is good into a charged battery. Jim
 
When you say you "diconnected the battery and was reading 9.8 volts on the cable ends with the tractor running,"

For one I never do that and second, the open circuit unloaded voltage output of 9.8 volts doesn't surprise me all that much. Its to what voltage a good working charging system CAN RAISE THE BATTERY VOLTAGE (IE when an actual LOAD is applied NOT open unloaded) by running at X volts OVER the battery voltage and pumping X amps through it.

Are you sure of the voltage and polarity of that alternator??????????????

John T
 
If it is all original, it will be a 6v pos ground Delco generator. Probably max output of 15 amps or so. I think he was sold a 12v battery when he asked for a 6v. Jim
 
Well I changed the voltage regulator and the battery is showing charging on the volt meter on the tractor and reads 6.5 volts with my digital volt meter. As for the first battery it is still on the ground reading 11.8 volts.
Thanks to all for their input
 

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