Exploded view of light switch
- Thread starter Tveditr
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rotorwrench
Well-known member
There are three distinct types even though they are all similar. One was for very early cars but was replaced with a little better design early on. The second was still early in 28/29 for the early type headlamps but it has the bale and the later 3-position switch plate. The third is the late design for "TwoLite" head lamps with the 4-position switch plate. There are different length bodies on them that required different length bales so a person has to know what they have.
If yours is still in decent restorable condition, it's usually well worth the effort to restore it. If it's a later repro then it doesn't matter so much. The early headlamps only had one beam brightness then the twolite provided high and low beam brightness levels. The modern repros have deep contact terminal buttons on the switch plate and can be hard to operate due to that. It can damage some of the modern contact spiders because of the extra force required to turn it.
If yours is still in decent restorable condition, it's usually well worth the effort to restore it. If it's a later repro then it doesn't matter so much. The early headlamps only had one beam brightness then the twolite provided high and low beam brightness levels. The modern repros have deep contact terminal buttons on the switch plate and can be hard to operate due to that. It can damage some of the modern contact spiders because of the extra force required to turn it.
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The problem I am having is a bad short problem. It started at the horn which got very hot. I cut the wires going to the horn, but there is still a bad drain on the battery. I assumed that the short was coming from the light switch. I have now taken it apart but don’t see any possible shorting out points yet. The lights were also not coming on at the proper positions from the steering wheel switch. I thought that was also a clue. So now I am not sure if I need to rebuild or continue chafing the short to the lights. This is a 30 coupe with cowl lights.
Joe K
Well-known member
As you assemble the switch, you want to be sure the switch upper housing "indent" meets a similar recess on the bottom of the switch body "receiver" on the bottom of the steering column. (It is possible the recess is "up" if the switch body receiver is not assembled properly to the steering gearbox.)
As you assemble the upper switch body to the receiver, you want to be sure your light switch handle at the steering wheel points "down." Many use a thin wooden stick bent between the spokes of the steering wheel to assist in keeping the light switch knob located for assembly. As you look at the switch spider on the bottom of the light switch rod, the horns on the spider should be "up & down" similar and matching the handle position. (it is possible to assemble the spider 90 degrees out of phase.)
Before you place the upper switch body to the column examine the position of the switch "contact slider" in the top of the body. You'll see two curved slots and in these smaller slots to take the spider fingers - the two slots to receive the spider should be aligned with the outside indent in the upper switch body - and thus will match and be enabled to go onto the spider as you place the upper switch body.
THEN - you run your wiring harness out the hole in the lower switch body. As you look at the upper body, you'll see by virtue of a slot and an "interior indent" the switch contact plate goes in the upper body only one way and this with the plate locating notch "down". And by the same upper body interior indent the lower body cover can be placed only with the hole for the wires pointing "forward." A small drain hole in the lower body points "down." (Gravity is a force for water)
Then assemble the lower switch body to the upper body. The two protruding "****" on the sides of the upper body will engage the fractional turn recesses of the lower body to hold the switch upper & lower halves together.
Then press the entire switch assembly "up" into the bottom of the column, compressing the spring under the spider, engaging the spider fingers with the switch slots, push and hold and engage the bail to hold it all together.
The genius of the Ford design is it can only be assembled "one-way" to result in proper function. The failure of the design is that there are "failed assembly alternatives" which if you're not aware, you can fall into. Its a design which counts on "assembler knowledge" to get right.
I looked twice at my directions above with a light switch body in my hand. I don't think I missed anything.
Hope this helps. There really is not a good picture or description of the assembly and its assembly pitfalls anywhere in the literature.
Joe K
As you assemble the upper switch body to the receiver, you want to be sure your light switch handle at the steering wheel points "down." Many use a thin wooden stick bent between the spokes of the steering wheel to assist in keeping the light switch knob located for assembly. As you look at the switch spider on the bottom of the light switch rod, the horns on the spider should be "up & down" similar and matching the handle position. (it is possible to assemble the spider 90 degrees out of phase.)
Before you place the upper switch body to the column examine the position of the switch "contact slider" in the top of the body. You'll see two curved slots and in these smaller slots to take the spider fingers - the two slots to receive the spider should be aligned with the outside indent in the upper switch body - and thus will match and be enabled to go onto the spider as you place the upper switch body.
THEN - you run your wiring harness out the hole in the lower switch body. As you look at the upper body, you'll see by virtue of a slot and an "interior indent" the switch contact plate goes in the upper body only one way and this with the plate locating notch "down". And by the same upper body interior indent the lower body cover can be placed only with the hole for the wires pointing "forward." A small drain hole in the lower body points "down." (Gravity is a force for water)
Then assemble the lower switch body to the upper body. The two protruding "****" on the sides of the upper body will engage the fractional turn recesses of the lower body to hold the switch upper & lower halves together.
Then press the entire switch assembly "up" into the bottom of the column, compressing the spring under the spider, engaging the spider fingers with the switch slots, push and hold and engage the bail to hold it all together.
The genius of the Ford design is it can only be assembled "one-way" to result in proper function. The failure of the design is that there are "failed assembly alternatives" which if you're not aware, you can fall into. Its a design which counts on "assembler knowledge" to get right.
I looked twice at my directions above with a light switch body in my hand. I don't think I missed anything.
Hope this helps. There really is not a good picture or description of the assembly and its assembly pitfalls anywhere in the literature.
Joe K
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Joe K
Well-known member
Another issue that many find is that ALL the reproduction parts for Headlights & Wiring are of the "twolight" variety. The earlier "Type H" Model A headlights & supporting switches (until about March-June 1929) are distinctly different electrically, and so far, except for Type H light sockets and plugs, have not been reproduced.
You can tell a Type H headlight switch from a TwoLight switch. The Type H switch has FOUR contacts. The TwoLight switch has THREE contacts.
Mixing an early 4 contact switch with Twolight harness/switch plate can result in the symptoms you're having.
A solution to this is offered in using a Twolight switch and Twolight Harness together and modifying the harness to light a Type H headlight. There will be one additional contact which will have to be unused.
Another solution is to modify a Twolight harness switch plate to work against a Type H switch. This may involve generation and incorporation of additional or relocated contacts.
I myself have Type H headlights and have reverted to a Type H system using this second methodology and reworked a Twolight wiring harness.
Another issue which can create problems is in the Headlight "plugs." The original wiring harnesses were based on soldered in place "bullet-ends" but all the wiring harnesses have "crimped on" bullet ends. These can get mis-placed in poor quality bullet end holders which are part of the plug system and cause shorts or intermittant lighting.
Unfortunately, the reproduction parts for the Ford Lighting System of all kinds are much in need of "quality upgrade." Cheap for these began in the J.C. Whitney era, and we still haven't gotten out of the woods on this.
Joe K
You can tell a Type H headlight switch from a TwoLight switch. The Type H switch has FOUR contacts. The TwoLight switch has THREE contacts.
Mixing an early 4 contact switch with Twolight harness/switch plate can result in the symptoms you're having.
A solution to this is offered in using a Twolight switch and Twolight Harness together and modifying the harness to light a Type H headlight. There will be one additional contact which will have to be unused.
Another solution is to modify a Twolight harness switch plate to work against a Type H switch. This may involve generation and incorporation of additional or relocated contacts.
I myself have Type H headlights and have reverted to a Type H system using this second methodology and reworked a Twolight wiring harness.
Another issue which can create problems is in the Headlight "plugs." The original wiring harnesses were based on soldered in place "bullet-ends" but all the wiring harnesses have "crimped on" bullet ends. These can get mis-placed in poor quality bullet end holders which are part of the plug system and cause shorts or intermittant lighting.
Unfortunately, the reproduction parts for the Ford Lighting System of all kinds are much in need of "quality upgrade." Cheap for these began in the J.C. Whitney era, and we still haven't gotten out of the woods on this.
Joe K
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Mike V. Florida
Well-known member
GRutter
Senior Member
If you are experiencing battery drain, check the voltage cut-out on the generator.
When not running, the contacts in the cut-out should open, and disconnect the generator from the battery. If the points stick, the generator remains connected and you will have battery drain - could also damage the generator field windings.
When not running, the contacts in the cut-out should open, and disconnect the generator from the battery. If the points stick, the generator remains connected and you will have battery drain - could also damage the generator field windings.
Describing switches as for "one bulb" or "two bulb" is confusing, since Twolite Deluxe cars were equipped with one-bulb headlight reflectors plus cowl lights. They are more clearly described as "3-position" (low beam-off-high beam) or "4-position" (park-off-low-high).
Marco's drawings are for the 4-position (Twolite) switch. 3rd pic shows a 3-pos switch plate with lower housing and a complete 4-pos on the right. 4th shows a complete 3-pos with an extra contact assembly.
3-pos wiring: Top - Battery, continues to brake switch. Bottom - tail light. Left/right - dim/bright (not sure which).
Joe K
Well-known member
Hence my descriptor of "Type H" - which are characterized externally with the vertical fluted lens, and "Twolite" (sic TwoLight) which are characterized by the more common "arc curve" lens.
I had to re-word my descriptor above a couple of times - and correct in several places where at one point I call something A - and another point I call it A'.
Uniformity in description is an aid to communication.
Joe K