My question would be: since you have a new 12V battery, the wiring needs redoing etc, why not take this opportunity to convert the truck to 12V Neg ground? At least some of the conversion has been done already, you could install a relatively inexpensive (compared to a new 6V battery) internally regulated alternator for dependable charging and have the capability to use the world of 12V accessories from phone and computer chargers to sound and/or navigational systems.

 

This is a good option but just not ready to tackle that sort of project quite yet. Worst case is I'll set aside the 12v battery for future conversion and go buy a 6 or 8v battery new. My problem is just confirming what the heck I have right now!

 

I agree with AXracer.

 

Taking out the seat makes for a far less contorting experience.

 

A 6V to 12V conversion is about the easiest project you can tackle, and a good way to start to bond with your truck! either way you are likely going to have to do some work on it, since it looks like you have a hybrid right now, so it's a matter of do you want to go forwards or back? If safe (potential shorts repaired) the 6V wiring is actually heavier than what 12V needs so you could postpone that part for a little while if going the upgrade route. Problem with the wiring is it is 65 years old, and the old lacquered cloth braid insulation is very brittle by now and is prone to cracking and crumbling from being disturbed or just from driving vibrations, even inside the taped portions or the harness where a potential short may be invisible, so be gentle and disturb it as little as possible until ready to replace it. Plus the original electrical system is run thru only 3 self resetting breakers rather than a fuse panel that protects each circuit as used today. An overload or short can result in most of the truck's electrical system suddenly to start randomly clicking on and off, lights, ignition and all. Not a fun situation, or an easy fix on the road late at night and/or far from home. If you thought it difficult to work under the dash, try doing it late at night in an unsavory location or on the side of the expressway in a pouring rain or snow storm by the light of a quickly dying flashlight with only a screwdriver and a pair of pliers, while your frightened and/or infuriated wife keeps repeating "I told you you shouldn't have wasted the money buying this piece of junk!".
Even if sticking with 6V a new replacement harness should be high on your to do list. It doesn't need to be one of the high priced cloth braid look reproductions, or from one of the heavily advertised manufacturers who are highly "proud" of their ($$$) "costs like it's made from gold" products, there are less expensive plug and play or universal harnesses available. If you haven't already done so call Classic Haulers Home - Classic Haulers F-1 Parts and ask them to send you one of their very handy and useful reference FREE print catalogs. They are also very knowledgeable, helpful and great to deal with people for your parts needs!

 

I borrowed a 6 volt battery from a friend and swapped at out just now. Truck fired right up. Does that seal the deal--6 volt?

 

Did you disconnect the battery with the engine at high idle and measure generator voltage?

The more I think about your situation, the more I believe the guy popped in a 12v taillight bulb just because he couldn't find the right (6v) one, same with the battery.

 

Won't have access to volt meter till weekend. But will do so then.

 

Did you go Positive ground?....how is your gauge reading?

 

Negative ground. Gauges reading good I think. Volt meter is right in the middle.

 

How about that wire position I keep asking about? That is very pertinent to the negative vs. positive ground.

 

Doc, sorry for the dodge of your question. Brutally honest to say I don't know how to tell so I can't answer your question without some help. As I said at the start, this is all pretty much new to me. My dad before he passed taught me all about wood working but unfortunately not engines.

 

Originally the truck was positive ground......when you rev the engine does the dash gauge show charging or discharging?

 

Moves slightly from middle to charging. Only slightly. The truck was negative ground when I got it---not to say the PO knew what he was doing or that it was set up correctly.

 

There's no shame in that. I didn't know either when I first started fooling with flatheads. Tell us which side of the coil is this wire attached to right here. Does it say "+" or "-"?



That would also depend on whether or not the generator is polarized to the current setup.