Sockets in Headlightbucket
 

I have a 1928 AA-truck.

I have 2 headlight buckets 28 style.
In there is a 5/8"socket for use of two wires in plug.

Problem is I have a brand new wireharness with 3 wires that go to the headlights.

Can I change the sockets in the buckets to about 3/4"? suited for 3-wires?
How is that best done?

Pietr

Re: Sockets in Headlightbucket
 

The problem with the pre March 1929 vehicles is that the headlights were "type H" (i.e. glass lens with "vertical" ribs - a sort of carry over from the Model T) AND the headlights were designed to have a single bulb with TWO filaments. One filament (driving light) at 21cp brightness and one filament (parking light) at 3cp.

So yes, you need but two wires to go to the headlight socket.

BUT in March 1929, Ford changed over production to the "Twolight" system which includes a reflector with two sockets and three wires to each headlight.

The biggest difference between Type H and Twolight is in the headlight switch. The Type H switch has four rotating contacts inside, Twolight switch has but three.

In the Type H switch you have but three positions. One way is ON, one way is PARK and the middle is OFF.

In the Twolight switch you have four positions. One way is PARK, the other way is two orders of brightness LOW, HIGH. With the centerish position being OFF.

Today, unfortunately, all there is available in new parts is the Twolight version. It is possible to use a Twolight version complete - including changing the switch entirely to a 3 rotating contact switch - and cut off the two "park" wires headed to the headlights inside the switch. You still have four positions. Depending on the wire you abandon/cut you can have PARK-OFF-HIGH (spare)

Many have tried to use a Twolight wiring harness with a Type H switch. It doesn't work for a variety of reasons - and may result in a short circuit.

My truck is July 1928 and I'm looking for a Type H switch. They're out there but not common. The Type H harness is actually harder. I have a friend who does computer "printing" and can make wiring plates. I'd have to come up with "contacts." And wires could be a Twolight wires de-soldered.


Right now its a work in progress.


Joe K

Re: Sockets in Headlightbucket
 

Other differences - bulb harness inside bucket has only 2 wires, connecting plug to conduit has 2 holes vs. 3, connectors are not crimped, conduit and cowl grommets are smaller, 1/2" vs. 9/16", column switch is soldered, not tabbed.

Just remove the 3rd wire, as Joe says, and deal with the differences.

Snyder's site shows the differences quite well.

Re: Sockets in Headlightbucket
 

Thank you Joe K. for your excelent reply.

I guess I'll keep the 2 wired headlights what was original. Then I have to skip one of the three wires.
Then see of I can get the lights working...
Succes with work in progress!

Pietr

Re: Sockets in Headlightbucket
 

Thank you Badpuppy,

I will keep the original setting two wires and hope get things working!

Pietr

Re: Sockets in Headlightbucket
 

The tabbed switch was first - and (go figure) is the switch shown in all the literature for non-Twolight.

I've only seen one tabbed switch on this forum - and that one was "pieces." The change-over from tabbed to the next iteration (bulb shaped switch enclosure) occurred like February/March 1928 - but I have not seen a definitive "after number xxx" on this.

The replacement bulb shaped Type H switch (4 contacts) began then. I have seen maybe ONE circuit diagram showing the four contact switch. The switch plate on these is notable in having four brass buttons on the plate perimeter, and one in the center - and not the similar "groups of three buttons" for the Twolight switch (3 contacts.)

In March 1929 the 4 contact switch was changed over to 3 contacts - and the Twolight/Cowl Light arrangement began.

Where it stayed well into the Model B/Model 18 era.

Joe K