If inductive timming light will work on 6 or 12 volt, if your light clips on to the bat of newer 12 volt then will have to use another vehicle for power then clip pickup lead for spark to your car. I do this when working on older systems.
Any 6 volt Ford I ever knew about was positive ground only, the clock I doubt will but the radio will not take a negative ground hook up, will burn the viabrator or voltage reg in radio out and may damage the rest of the radio.

 

"Any 6 volt Ford I ever knew about was positive ground only, the clock I doubt will but the radio will not take a negative ground hook up, will burn the viabrator or voltage reg in radio out and may damage the rest of the radio."

Can anyone tell me what to look for to be sure whether it is pos or neg ground? I had seen that the lead from coil to dist is an indicator (the small lead, in this case it is neg = neg ground but my brother installed the coil and said he thinks the old one was just marked "dist" and "gen" rather than pos and neg so?). The same goes for the battery..I suppose it is a possibility that it is connected backwards too but since everything works...I am at a loss. What would be the best use of a Volt/Ohm meter to help with figuring this out? I really do have some clue about cars, really but I am pleading "uh, duh, wha?" on this one.
It has been in the current configuration for years as far as I know and seems to be fine except for the tune issue..starter does it's thing, lights light, ignition fires (and the hard start is fuel/carb related I am almost certain), generator seems to be uh, generating...lol, etc. Only related item is that with so few miles put on per year, even with a maintainer for 6V it tends to go through batteries every year or two. If there is no advantage either way, I suppose it would be better that it be pos ground for the sake of the radio, etc and obviously ALL one way or the other.

 

If it were properly converted to negative ground, the ammeter would show discharge with the engine off and the lights on, with the battery hooked up neg to ground. The clock may work either way, and from things I've read, tube radios work on any voltage, any polarity. The heater fan may or may not turn the same way with either polarity, nothing else will care what the polarity is.

 

Factory radio's from the past that I remember had case connection and one insulated wire for the power supply along with speaker plug in or pig tail so when you mounted it to the dash it was bonded on one side. Sounds stupid but I never saw a Ford radio in a Chevrolet in the 6 volt line or visa versa, I was told this was a patent issue.
One point to ponder that I have ran into not Ford related was GM 6 volt, Chevrolet and GMC systems were opposite also with Chevy Neg ground and GMC Pos ground, their generators were also different as one produced neg the other pos as indicated to with a red or black tag on gen housing but if crossed into the other did not last very long, I still have bad memories of this event and remembered basic rules after that.
I never tested a Ford generator as all were known pos ground systems but wonder what would happen if wirred backwards.

At times when cold I did not like 6 volt systems all that well but could with a few tricks get them started but I have never tried to redo a system into something else as for all the trouble it wasn't worth the effort unless "sentenced" to it so to speak for lack of parts or sometimes exspence if I had a few years newer system that would bolt in.

I have not dealt in 6 volt for a while and so please forgive me if I sounded excited but I do love the chance to remember and learn more about it as with any thing else no matter how much a person thinks they know there is always, cannot be over stated always something new to learn.

 

Please forgive me but I thought of something else, some years back when I was still cutting my teeth and busting tires in a shop yet as I was just a farm boy and was not allowed near complex mechanical things to repair got to see a I think Ford, I know it was 6 volt and polarized different from then more standard 12 volt systems come in with the truck battery hooked up correctly yet shown discharged when charging and visa versa on the ampmeter. After questions and debate concluded that the system had worked OK last time used but after finding the battery dead accidently recharged it backwards to which the battery took.
A question asked was why not drain and recharge correctly but was thought after all that it would not last long and so the battery was replaced and all was well, I seem to think I have ran into this somewhere later also but cannot remember details.
Any one else run into this?

 

Alright, this seems completely logical to me and, unfortunately, it appears that the ammeter moves to slightly "charge" when this is done so I suspect that the battery and coil are hooked up backwards. One thing that confuses me about this is that the generator seems to have been functioning fine along the way as the battery isn't being discharged while driving the car? This brings me to the important question. If, as appears to be the case, it is hooked up backwards, is it as simple as switching the leads to the coil and the battery leads?
I am inclined to think that the battery needs to be fully discharged before this is done and then recharged using correct polarity and current flow but that brings me to another point. Can a conventional 6V battery charger be used and do you need to reverse the leads also (my initial thought is that the leads should be reversed so current flow is consistent with positive ground vs negative). Also, on that same line, does the regulator/generator hold a charge that needs to be removed so it can be energized with flow in the correct direction also? Can this be done simply by intentionally running the system clear dead with a slow drain (like the lights) to kill the charge in the battery as well as system?

Thanks again all!

 

If anyone needs to apologize it is me. For the long winded text and the silly questions. I sincerely appreciate any and all input you guys can give me and am grateful that I have the ability to learn about this strange (to me) system from those who know about them! Experience is a fantastic teacher and I need me some good learnin! I am pretty well educated and have alot of automotive experience but the most valuable thing I know is that when I don't know the truly smart thing to do is ask someone who does! So, thanks to all for your assistance and please, please keep it up. It is definitely welcome and appreciated.

 

I have over times ran into reverse polarity in Ford as nothing in the past 50 or so years barring tractors have a positive ground system,with that said as strange as it sounds the charging system will work whether hooked up right or wrong, it will just start to break down sooner.
While charging the swing to discharge on your ampmeter shows the incorrect flow of electricity not actual discharge if hooked up incorrectly and the system is realy putting out charge, it would be the same as hooking up the ampmeter backwards.
I have read back through other post's and would think basics first to determine what you have, then how to repair:
First make sure the battery is hooked up and charged at least some then get a digital, volt, ohm, meter or DVOM as they are called as it will by following the instructions supplied with it or with help also will determine for sure which way the polarity runs.
You should see a voltage reading around 6 volts if there is sufficent charge along with a positive reading when hooked up red lead to frame and black lead to bat post on starter solenoid.
If a negative reading is shown first see if the larger pos or + post is connected to the frame or motor, if it is then the battery has been reversed charged and as stated above should be thrown out and new installed correctly.
If the battery was installed backwards then as long as the battery was in good shape should only need reversed then recheck with your dash ampmeter to see if everything runs the right way.
Those batterys are the same as any other as when you charge them with a charger red or pos to pos and black to- or negative, it is only the way it is hooked into your vehicle that is different.
I hope this is help, there is more along with being able to determine polarity of a coil but at this hour I'll hold off on that as I'am done for the night.

 

I have a '53 customlime coupe. I just went throught all the issues your dealing with. I changed over to 12v via Ron Francies...But with regards to your fuel/vac issues here's what I had to accomplish...Carb rebuild(running single 2 barrel holly94), in-line fuel pump with filter...those old tanks can stir up something awful sediment wize!, new diaphram for pump, new intake man. gasket, points, condenser, cap rotor,...these engines can be forgiving but make sure your timing is spot on as well as setting your points between .14 - .16...I also changed out single pipe for headers from wirths customs back east, alomg with smithy's...the car purr's in from=nt and rumble's out the back as it should. Again flatties are a pain to fine tune. they can keep you guessing. usually poor proformance is vacumme leaks and pressure issues. a great site to access is flathead V8. good luck

 

Yes they are hard to tune but make sure the plug gap is 0.030 of an inch and the points as listed, I would however go for 0.015 gap the timming is set to the groove on the pulley, a personal note but at a mile high in altitude I add an additional 2 degree's before top dead center to the timming.
If coil is old, been in the car for quite a while would even think about replacing the coil with new as even though it might have a good spark when tested, if a few windings are shorted within the coil it will not reduce spark but will reduce build up time which when running down the road will not allow the spark to rebuild well enough to fire the cylinder completely. There used to be testers for this but I don't know if any are around anymore.
A thought to end all this for now but 6 volt systems even though good at the time was replaced by 12 volt because it took took half the amperage to deliver the same amount of power.

 

I'm at 3600ft. haven't noticed a difference, But at times I smell fuel...and burn rich...would my fuel pump be pumping to much? I really sould get a regulator in-line to monitor that...

 

Hi, here are my 2 cents worth.

It seems to be a common problem with some guys I know with flatheads, changed to 12 volt system and problem went away. If the spark is not good it will run like that, check your coil and wire, don't know if getting a higher output coil is an option if still 6 volts.

Good luck

 

I am really thinking I want to get the 6V right for now but am seriously thinking that there was a very good reason that the industry went to 12V (and I wouldn't be at all surprised if we see 24V or more coming up for alot of reasons). As for the tune issues...did pull the carb back apart..actually my brother did...he had the day off, I had to work... and said that the bowl was loaded with what looked like grey latex paint (like tank sealer flaking off?). There is no inline filter on it now (just the sediment bowl and the screen) but there will be one before the weekend is over! Full rebuild again, float level was right before but new powervalve, etc was put in with gaskets, etc of course..basically a re-rebuild. Radiator is out right now getting recored so will pick that back up tomorrow, hopefully get it running soon and go from there. Still have some concerns about the existing 6V system (particularly the coil having been reverse wired even though it is newish..last fall and wires, plugs, points, etc). Gotta get that thing running right way before snow flies so can get him excited about the flathead!

 

I'll keep this simple tonight as I have been getting overdone with all the theory, and by the way it sounds like with the carb cleaned out should fare better.

Mostly as stated before make sure pos large post on battery is to frame and motor and the battery has not been damaged or reversed.
If the coil was for your car and marked (bat) and (dist) you should be fine on the hook up.

I do and have used this test to determine polarity before with coils and Ill have to say right now that this sounds like something that was dreamt up durring a bout with a bottle of whiskey but it does work, must make sure your outfit is correctly grounded before beginning. I shall try to write this down, I cannot blame you if you dont want to do this but here goes.

To check the coil polarity first make sure points are open then lay a lead pencil on the block where it will stay and not roll off as you dont want to hold the pencil durring this test or you could get nailed.
Pull the coil wire out of the cap and with the key on, engine off and the coil wire with your fingers back a ways from the end hold the wire over the lead of the lead pencil about a 1/4 inch, then short the points out gently with a insulated screwdriver and release to generate spark.
As the spark goes through the lead notice if the orange flare of the spark is towards the block or towards the wire your holding on that lead, with 6 volt you may need to do this with as little light as possible and or pull the coil wire away a little more. Be carefull as if you pull back too far, the spark may still run up or come out of the wire and get you.
If the orange flare is on the block side of the lead on the pencil the coil is correctly polarized, if the orange flare is towards the coil wire you are holding the coil is backwards.
Good luck!

 

With the original 6v system, plug gap is only .025". Champion plug (H-10) are notoriously lousy, Autolite #216's are much better. There is nothing intrinsically wrong with a 6v system, but there is less margin for bad connections or frayed wires.

I'd be willing to bet the fuel smell is just the normal odors from an open system. All garages used to reek of gas! We're so used to closed systems with charcoal canisters nowadays that even a small whiff seems wrong, but that's how carbs and vented gas tanks are.