I have an auxiliary Ford tail/stop light that I want to use on my '27 Touring and was wondering what the numbers were for the two bulbs that are used in that tail light. The light uses one single filament bulb and one two filament bulb but none of the 6 volt bulbs I have will work. They either interfere with the glass lens or the prongs do not line up in the sockets.
Have used a #81 6v 15cp? (7 watt) for the tail lamp bulb, the horizontal one, it clears the tail lamp lens.
As for the vertical bulb, a larger 6v 21cp works for the stop lamp.
On one of my T's the tail lamp bulb is a special LED that casts light straight out, but has radial LED around the base to illuminate the tag, this bulb is found on the net under Model A LED bulbs.
Thanks Dan. Is the upper bulb a #55? I can't tell from your picture if the stop light bulb is a dual or single filament bulb. My light seems to have a dual contact socket but I don't understand why. I assume only the lower bulb is on when the lights are turned on and that the upper bulb only lights when the brakes are applied.
Don't remember that upper (brake lamp) bulb i.d.
But it is a single contact, 6v 21cp or so, the lamp should have single contacts at the brake and tail lamp receptacles.
Of course the plug in contact for the wiring is two contact, and the lamp housing feature of the receptacles sends one contact to the tail and the other to the brake lamps, since the plug carries the two wires, one from the brake lamp switch, the other for the tail lamp.
Note the single brass contact for the upper brake lamp bulb.
The male Bakelite plug is of the two contact style, like the headlamp plugs for the dual filament bulbs.
That helps a lot. Thanks. I think I can find a single filament bulb for the Stop feature that will work. There was a dual filament bulb in the top part of the light when I got it but it was broken and there were no markings on it so I assumed a dual filament bulb was correct.
Dan, what kind of reflector is that ?? Mine doesn't have one. I just lined with the shiny side of alum.foil.
Mine has the reflector too and it is common to other non-Ford script lamps so you might be able to find one in a another lamp that can be used for parts. The almost identical non-Ford script lamps were fairly common at Hershey last year and were not too expensive.
Exploded view of the accessory '26-'27 Ford Stop/Tail lamp.
This original reflector is silver plated, and screws to the back of the lamp housing. Val is right, you have to search swap meets for a replacement or buy a junk lamp to cannibalize. These lamps were mfg by Hall, and you can usually find the Dodge Bros lamps at swaps a bit cheaper than Ford script ones.
And when going over these lamps, the original way the lens was done was to rivet with a hollow soft alum rivet the glass lens to the nickel plated rim sandwiched with a cork gasket, (you can get new gaskets from the vendors) and with the 'stop' stencil plate on the back of the assembly. The hollow rivets allow the small machine screws to secure the rim and lens to the lamp body.
If you don't do it that way, when you remove the rim later to change a bulb, the glass lens can fall and break, and that lens is rather rare..
I use alum Pop Rivets to do this, remove the nail driver, thin the Pop rivet shaft some and the length, then use it to assemble the lens and rim. Looks authentic and saves that rare glass lens!
George the next best thing to a reflector is to paint the inside white. It really works better than aluminum foil. My guess is the wrinkles in the foil is reflecting light everywhere. White seems best imho.
I used "bumper chrome" spray paint on the inside of my brake light housing which was originaly painted black. It made a big difference. Dave
While there is and has been a miniature lamp standard since the 20's....there is a lot of looseness and poetic license in what people do sell.
You say pins from your bulb box don't line up and that has to do with part of the standard having opposing 'pins' and part of the standard using what are called indexed pins on dual filament lamps. It's easy enough to move from one to the other...it's called a file, but the other way would be to change the socket. One pin is usually enough to keep it in place.
Dan says he uses a Number 81 lamp for the small one and it just fits. The generic standard for this lamp is I/6.5V/1.02A/BA15S/G6/CL/500H. This is a nominal 7 watt but not quite.
There is also an 8 watt lamp in this generic series, big deal, not enough to make much difference...yet there is also a 15 watt lamp that can match the specification.
It is the BA15S/G6 that determines size. Find a lamp that has the same BA15S/G6 rating, at any wattage, and they are interchangeable. There comes a point I guess where you have to worry about total connected amps on the light circuit, but an even brighter one does exist in the 2.5 A one.
Thanks George that is very helpful information. I actually got very lucky today as I was browsing through a antique store and found a Mazda automobile lamp kit with two head and two tail lamp bulbs still in it. It was $10 and all the bulbs are good so I feel like I got a good deal!