My new Model A hasn't run for a year or two and the previous owner had replaced the coil and not hooked it up and moved the battery. I'd like to figure the electrical out and see if I can get it going. There are 2 wires from the bottom of the coil, a blue one on the passenger side and a black one on the driver side, I don't know where they go or what they hook into, There is also a white wire that comes out of the little box under the coil that is not hooked upm the box has 2 small levers on it that I have no idea what they are. He moved the battery under the hood and had the ground strap hooked to the negative post, is that right? I've attached a couple of photos and any help would be greatly appreciated, I'll buy a manual but I'd really like to hear it run. And I forgot, where is the battery supposed to be? Thanks.
Electrical, Try And Figure Out
- Thread starter irvan
- Start date
Tom Wesenberg
Well-known member
The battery should be under the driver's feet.
The two "levers" are wing nuts that hold the cover on the terminal box. The two studs join wires together. The ammeter is connected by two short wires to the terminal box, one to each stud. Power from the generator goes to one stud, through the ammeter, then to the other stud and back to the battery. The ammeter ONLY shows the charge going to the battery, and not the full output of the generator. The ammeter also shows the drain coming from the battery if the drain is more than the generator output.
One wire on the coil primary leads to the ignition key, which leads to the distributor points. The other terminal should have 6 volts from the terminal box.
The battery should be POSITIVE ground. Once it connected correctly you can polarize the generator by jumping a short wire across the two terminals on the cutout for one second.
It won't cost too much to move the battery to the correct location and buy a new wire harness to clean up that mess.
The two "levers" are wing nuts that hold the cover on the terminal box. The two studs join wires together. The ammeter is connected by two short wires to the terminal box, one to each stud. Power from the generator goes to one stud, through the ammeter, then to the other stud and back to the battery. The ammeter ONLY shows the charge going to the battery, and not the full output of the generator. The ammeter also shows the drain coming from the battery if the drain is more than the generator output.
One wire on the coil primary leads to the ignition key, which leads to the distributor points. The other terminal should have 6 volts from the terminal box.
The battery should be POSITIVE ground. Once it connected correctly you can polarize the generator by jumping a short wire across the two terminals on the cutout for one second.
It won't cost too much to move the battery to the correct location and buy a new wire harness to clean up that mess.
steve s
Well-known member
I appreciate the urge to just get it running, without first doing a full restoration. But, please resist the urge to just try things. Your hookup should make sense to you; make yourself a diagram.
Here's an original wiring diagram picture that should help. It sounds like your system has seen enough changes that you shouldn't make too much of the wire colorings you find (the electrons don't care, either).
One change that Ford made after this picture was published, and which is a really good idea, is to reroute that black wire that is shown going from the coil to the top lug on the terminal box so it goes to the other terminal lug. That way the current drawn by the ignition system will show on the ammeter--this turns out to be very handy.
Lots of mods in your photo; would be good if you had a friend who was comfortable with electrical. If it was converted to negative ground, there's a good chance it was also converted to 12V. That's a different coil, or an added ballast resistor. If you can't ask the guy, maybe you can tell by checking some of the bulbs. In any event, grounding to the firewall is not so good. Also, you're sort of on your own with that non-original starter switch--there's probably a different ignition switch, and who knows how the coil was wired in. In the original, the coil was between the battery and the ignition switch, so it is always electrically hot.
Steve
Here's an original wiring diagram picture that should help. It sounds like your system has seen enough changes that you shouldn't make too much of the wire colorings you find (the electrons don't care, either).
One change that Ford made after this picture was published, and which is a really good idea, is to reroute that black wire that is shown going from the coil to the top lug on the terminal box so it goes to the other terminal lug. That way the current drawn by the ignition system will show on the ammeter--this turns out to be very handy.
Lots of mods in your photo; would be good if you had a friend who was comfortable with electrical. If it was converted to negative ground, there's a good chance it was also converted to 12V. That's a different coil, or an added ballast resistor. If you can't ask the guy, maybe you can tell by checking some of the bulbs. In any event, grounding to the firewall is not so good. Also, you're sort of on your own with that non-original starter switch--there's probably a different ignition switch, and who knows how the coil was wired in. In the original, the coil was between the battery and the ignition switch, so it is always electrically hot.
Steve
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Tom Wesenberg
Well-known member
If your original battery holder is missing, try to find an original. Don't worry about the bottom plate being rusted away (as many are), because quality replacement plates are available and can be spot welded in place, like the original was.
The black frame in these pictures is a very poor quality repro and won't fit like the original. The original frame fits on top of the frame lip, but due to the poor quality fold on this repro part it won't fit on top of the lip. It might fit under the lip, but my friend chose to find a good original. If you can't find a good original battery holder locally, then you could try Bert's in Denver 800-321-1931.
BILL WILLIAMSON
Well-known member
Get your wiring hooked up EXACTLY as the diagram shows, then it is easier to deal with any problems in the future.
Bill W.
Bill W.
marc hildebrant
Well-known member
With regard to the wiring diagram,
Ford made a change during the Model A build time, where the ignition power was changed so that the ignition current went through the amp meter. The picture above shows the early set up with the ignition current NOT going through the amp meter.
Marc
Ford made a change during the Model A build time, where the ignition power was changed so that the ignition current went through the amp meter. The picture above shows the early set up with the ignition current NOT going through the amp meter.
Marc
Mike V. Florida
Well-known member
found the hole in the floor and I think the old battery tray (he had "modidied" it to use under the hood. Hopefully you're not to tired of questions yet. Does the battery tray mount on the bottom of the floor or do the "feet" go on top and does the positive post go towards the front or back when in the holder? Thanks, I appreciate the help.
Attachments
Irvan,
This should help you to picture the battery box:
http://parts.modelastore.com/show_Product.asp?ID=3408
The front side hooks to left frame rail and the rear part hooks to the crossmember.
The bracket part of tray sits at a 45 degree angle with the square plate straight in relation to the car itself.
The holes should still be there along with a hole to mount the + battery cable.
Disregard this part I miss-read the picture:
From your first picture it looks like your car might have hydraulic brakes ... hence the reason for putting battery under the hood.
There are battery boxes available that have mounts to hook up the master cylinder to the stock brake pedal linkage. The battery is located under the floor just like the stock setup.
Example: http://parts.modelastore.com/show_Product.asp?ID=3186
The positive terminal goes toward the rear to hook to the frame with the hole in the crossmember, mentioned above.
Also when you buy battery cables remember that most auto stores have 12 volt cables which are too small for 6 volt systems.
This should help you to picture the battery box:
http://parts.modelastore.com/show_Product.asp?ID=3408
The front side hooks to left frame rail and the rear part hooks to the crossmember.
The bracket part of tray sits at a 45 degree angle with the square plate straight in relation to the car itself.
The holes should still be there along with a hole to mount the + battery cable.
Disregard this part I miss-read the picture:
From your first picture it looks like your car might have hydraulic brakes ... hence the reason for putting battery under the hood.
There are battery boxes available that have mounts to hook up the master cylinder to the stock brake pedal linkage. The battery is located under the floor just like the stock setup.
Example: http://parts.modelastore.com/show_Product.asp?ID=3186
The positive terminal goes toward the rear to hook to the frame with the hole in the crossmember, mentioned above.
Also when you buy battery cables remember that most auto stores have 12 volt cables which are too small for 6 volt systems.
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tbirdtbird
BANNED
it sure is hard to imagine why anyone would mount the battery to the firewall. and the ground to the firewall will do nothing. You will be glad you are putting it right
Mike V. Florida
Well-known member
I thought the same thing but I've seen many pictures of just that, batterys mounted to the firewall.
Keep them coming, the only dumb or stupid question is one not asked. Answers, that is another thing all together.
700rpm
Well-known member
Irvan, it would help you immensely, I think, if you could find a car that has been put to right and thoroughly study it for your problems. Actually seeing how a battery box should be, how a starter is fixed, and so on, will help you understand what suggestions you receive here. If you go to: http://www.mafca.com/location.html and scroll down to Kansas there are several members listed, some of whom may be near you, or can refer you to a local chapter. If you have a local chapter, join it. You will find more help than you can imagine.
Brentwood Bob
Well-known member
find some local help as ray has mentioned. Best thing you can do first. Working on your car without good advice is a poor first choice. BobBob
Bruce Adams
Well-known member
i DO like the battery switch location in the firewall where you can flick iton and off with your toe.
I suggest you consider keeping it when you hook up rhe battery where it was originally.
It will require a longer zero or double zero gauge cable. You can purchase them at West marine and many other marine stores. Negative cable should be black.
Did he convert to 12 volts?
With all the other hoolie goolie stuff, he might have done it during one of his electrical exercises.
Welcome and best of luck !
I suggest you consider keeping it when you hook up rhe battery where it was originally.
It will require a longer zero or double zero gauge cable. You can purchase them at West marine and many other marine stores. Negative cable should be black.
Did he convert to 12 volts?
With all the other hoolie goolie stuff, he might have done it during one of his electrical exercises.
Welcome and best of luck !
Kevin - Illinois
Senior Member
When I brought home Dad's old Coupe in 2006 I also was in a hurry to get it running, but there were some issues with wiring. I started to repair them and quickly realized that it was a lost cause. I ordered a new wiring harness from Snyders along with many individual wires. After taking out the old harness I realized it was the smart thing to do as it was in horrible shape and most likely could have started a fire.
I agree with Bruce as well that you should check to see if it's 6 or 12 volt.
I agree with Bruce as well that you should check to see if it's 6 or 12 volt.