Headlight Question

[captain marty]

There are no dumb questions, right?
Learning about my truck lights and wires has been fun.
Question: The headlight bulb has 2 filaments. I believe the short one is on for driving. My question is: are both filaments on when high beams are swithed on?
An auto electirican I am not,
Marty

[lfg1931]

It's one or the other. Not both at once.

Larry

[Bob C]

If you have "Twolite Headlamps" the lower filament is high beam and the upper filament is low beam.

Bob

[Neil Wilson]

Your avatar is of a '28. Original 1928 headlamps had only one bulb and the switch had only a headlamp, off, parking. The headlamp was 21 candle power and the parking was 3 candle power. The "Twolite Headlamps" didn't start until March 1929. They had two bulbs. One bulb was as indicated by Bob. The second bulb (for A/AA's without cowl lamps) was a parking light.

[captain marty]

You are right Neil, my headlights have only one socket. The bulb has 2 seperate filaments, one for driving and one for high beam I believe. I plan on finishing up this weekend and testing all my new lights and hope they work like I think they will.
Marty

[SHELBY MESSER]

If possible use your old head light socket and back to the plug where the wire harness plugs in! The replacement head light socket are not lined up where the socket plug in to the wiring harness, the connectors fall in between the sockets and shorts or contacts 2 connection at once. Most of the old light sockets have good wires but no insulation. re-insulate the old wire or check the new wire connector with the old one. Note the difference in the position of the 2(old & new) where the light socket meets the wiring harness!!!!

[spectria]

If you have "Twolite Headlamps" the lower filament is high beam and the upper filament is low beam.

Bob

Bob, when you say "lower filament" do you mean inside the same bulb, or in a second single filament bulb?
The TwoLites had 2 separate bulbs, correct?
Learnin...

[Bob C]

The Twolite came out in Feb. 1929, it has high and low beam in one bulb. If the car did
not have cowl lights then there was a second small bulb above the driving light bulb for
the parking light. See page 322 of the Service Bulletins.

Bob