Hi Everyone, I have a 1949 F-1 with a 239 flathead. Can a 6 volt battery be so dead that the truck won't keep running after the jumper cables are taken off?
This is what is happening, sometimes it runs for a few seconds other times a few minutes after being disconnected from the jump battery.Also, when you turn anything electrical on (directionals, lights, blower motor) it quits right away. Is it the battery or something else?(generator, regulator)
Thanks. Kevin

 

What kind of ignition do you have? Electronic or points? The short answer is yes, it's possible, but it can also point to other things, too.

 

Verify the battery voltage with a volt meter, also check battery posts & ground connections. How old is the battery?

 

it’s a points ignition and battery voltage is 1.10.

 

A battery with a shorted cell can do that.

 

did check and clean posts and ground. Voltage is 1.10 and battery is 12 years old.

 

12 years old? 1.10 volts? Need a new battery.

 

Check the generator output and voltage regulator.

 

It's possible that not only is the battery dead (which it is for sure) but also that there's a short in it dragging the generator voltage down. A 6V battery is considered dead if it measures less that 5.8V, so yours at 1.1V is dead dead dead. A typical 6V starter battery has an average lifespan of 3-5 years, more modern car batteries can last 10-12. In either case, this battery owes you nothing.

A Lead Acid starter battery has many lead plates that deteriorate over time, leaving lead deposits at the bottom of the cell. If these deposits get large enough, they can create a dead short across the plates. That's most likely the case here.

 

While you are replacing your battery, check over your battery cables too. If you see any greenish corrosion your connectors the cables are probably shot. Make sure you don't scrimp here. Regular replacement cables for a 12v vehicle won't cut it due to the higher current demands. For a 6 volt system they should be at least 0 AWG. But myself I would go with 00 or 2/0. Many know those sizes as "double ott" or "two ott".

 

A generator will supply sufficient current to operate an engine. Once started, the battery cable can be lifted from the terminal and the engine should remain running. If it doesn't then the generator/regulator is bad.

 

I got a new battery and still no charging. I by passed the regulator with a jumper wire and the generator shows charging at the amp meter in the dash
and on a volt meter at the battery terminals.
My question is where can I purchased a quality 6 volt regulator?
(even new one can be problematic)

 

I sense that you want to keep it stock...but just for thought...an option is to go with single wire 12v GM alternator and replace the internal 12v regulator with a 6 volt regulator. I did this several years ago on a 1930's prewar non-Ford car. I bought a rebuilt GM alternator (about $45) and installed a 6 volt internal regulator (less than $20). In this case, I had little choice as my parts were missing and any replacement parts were either not available or very $$$$$. They make a bracket for mounting an alternator to the flathead v8.
Like CharlieLed said above, pull the battery cable and if engine does not continues to run, it is either the gen or regulator. To check just the generator, I used to power the generator terminals and the armature would spin on its own (belt removed of course)... telling me the generator was good.
If you dont already have a shop manual, get one....it should describe in depth how to check the components with a multi-meter.
The 6V regulator seems to be available out there, I see NAPA shows a listing....not sure of their quality, the Echlin brand has been around a long time... good luck

 

Which Voltage Regulator terminals did you jumper? If you jumpered the Field and Battery terminals, you may have polorized the generator and it started working again. If that's the case try normalizing the wiring again and see if its now charging. If it doesn't then I too would replace the Voltage Regulator.
If you do need a new one check with NAPA. Or you could order one from OReilly, Auto Zone, whatever your favorite auto parts store is.

 

I did polarized the regulator/generator right after putting in the new battery. Then I jumped from A and ground on the generator to bypass the regulator and the battery showed charging about 7.8 volts