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Rotating Headlight relay modification.

I think I may have posted what I found about the original headlight wiring.
It all had a common ground splice in the wiring harness that runs across the front of the radiator frame.
That could be a potential problem due to age in these cars.
I upgraded all that wiring forward of the radiator and while at it, I reoriented the relays to this position.

View attachment 836557

I'm sure the circuits work fine -- but, I think the wiring harnesses would look better under the dash. Either that or make a cover for them. It looks a little discombobulated. From a yacht and nuclear electrician.
 
I'm sure the circuits work fine -- but, I think the wiring harnesses would look better under the dash. Either that or make a cover for them. It looks a little discombobulated. From a yacht and nuclear electrician.

You are primarily looking at the "illumination " relays and fuses.
The 30 amp CB does feed the motor relays, and via a common terminal, the bulb illumination circuit.
The new CB takes the place of that little self resetting one that was not accessible behind the driver's kick panel protecting the motor circuit.
If neatness is your concern go back to post 24 when I had the relay connectors pointing up.
I chose to rotate them downward under the relays to prevent dirt accumulating in the socket pockets.
Function over form.
Perhaps if I had placed them at 6 o'clock originally the work would be more acceptable.
Space is limited.
Another place to locate them under the hood would be on the fender which I think would look no better since it would show no matter what.
I chose a clean fender on this build.
I've got two "drivers" with the relays on the fender.
It also would make little sense to locate those two relays under the dash since the idea of those relays is to move the power source for the light bulbs close to the alternator and bulbs themselves and not go back and forth with more, longer wires.
These are safety sensitive headlight items and you need ready access to them if possible. (The fuses, etc.)
Hiding them in an inaccessible place is not a good option.
The buckets can be rotated by hand if necessary but the light bulbs really need to work.
(I think that answers the other poster's question about the buckets not moving unless powered?)
I thought about a cover for this area but room is the problem again.
There isn't any room for a cover with the battery installed.
The battery does a good job of hiding them and being on the rear of the radiator frame does that as well.
 
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Or, lol...does somebody have good motors for sale? And the switches/relays/wiring harnesses?

Headlightmotorman can repair your motors
He has a web site
Do you not have any motors at all?
I know and appreciate the desire to come up with something else readily available.
In our case , fixing the motors that were designed for the system was money well spent to get the car finished.

See the new switch info in this thread.
Should run you about 10 dollars each on the web.
Post 30.
The standard Bosch relays will work for the rotation circuit but you will need new plugs.
I think someone sells an adapter harness if that is better for you.
Headlightmotorman again or post 28?
 
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Headlightmotorman can repair your motors
He has a web site
Do you not have any motors at all?
I know and appreciate the desire to come up with something else readily available.
In our case , fixing the motors that were designed for the system was money well spent to get the car finished.

See the new switch info in this thread.
Should run you about 10 dollars each on the web.
Post 30.
The standard Bosch relays will work for the rotation circuit but you will need new plugs.
I think someone sells an adapter harness if that is better for you.
Headlightmotorman again or post 28?
I got with Topher on line and asked him about the parts. No, I have no motors at all, I have all of the hardware just no motors. It's in a 67 Coronet so I didn't have any to begin with.
 
So is Topher going to hook you up with motors? If not, I think I still have an extra set up in storage.
 
You are primarily looking at the "illumination " relays and fuses.
The 30 amp CB does feed the motor relays, and via a common terminal, the bulb illumination circuit.
The new CB takes the place of that little self resetting one that was not accessible behind the driver's kick panel protecting the motor circuit.
If neatness is your concern go back to post 24 when I had the relay connectors pointing up.
I chose to rotate them downward under the relays to prevent dirt accumulating in the socket pockets.
Function over form.
Perhaps if I had placed them at 6 o'clock originally the work would be more acceptable.
Space is limited.
Another place to locate them under the hood would be on the fender which I think would look no better since it would show no matter what.
I chose a clean fender on this build.
I've got two "drivers" with the relays on the fender.
It also would make little sense to locate those two relays under the dash since the idea of those relays is to move the power source for the light bulbs close to the alternator and bulbs themselves and not go back and forth with more, longer wires.
These are safety sensitive headlight items and you need ready access to them if possible. (The fuses, etc.)
Hiding them in an inaccessible place is not a good option.
The buckets can be rotated by hand if necessary but the light bulbs really need to work.
(I think that answers the other poster's question about the buckets not moving unless powered?)
I thought about a cover for this area but room is the problem again.
There isn't any room for a cover with the battery installed.
The battery does a good job of hiding them and being on the rear of the radiator frame does that as well.

The distance between alternator and lights through the bulkhead and out is maybe 8 or nine feet -- voltage drop on 14 AWG would be minimal through that distance (10 AWG even less). There is a space under the battery tray that would hold these circuits / harnesses. That might be an option in the future. Note: I give you a lot of credit. I struggle keeping the original configuration operational. I've been thinking about buying the new relays to improve dependability.
 
I am looking for a motor as well mine came with only one
1966 charger
 
Hey Speedbird who manufactured those nifty limit switches you used. your link is no longer working. Thanks
 
Thanks for bringing this thread back.
I agree the main issue is the common relay , and 1 motor spinning faster than the other.
 
Hey Speedbird who manufactured those nifty limit switches you used. your link is no longer working. Thanks

This is what to look for.
It's a drop in except for the bracket install.
IDK where to source them since "covid".
You'll have to look around and see.
Probably cost 3 times a much now
What did I pay?
10 maybe?
The system is working reliably, still.
I know a complete rewire isn't for every one.
But if a car is being completely gone through, it's nice to have a better system.
Headlights being a safety item.
.
Limit switch screen capture.jpg
Limit switch screen capture 2.jpg


There was a something that I had to change on the first pages as I built the car.
Just to be clear and easy this is how to make it work if anyone wants to try.
(After I had to add the "aux" relay.)
Wiring can be done as they see fit.
1702931093307.png
 
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Looking at your photos it looks like you cut center wire. So it’s NO
 
That has a lever which you do not want.
Look for a source for an E72 40AT
The same switch with the unwanted lever would be E72 40HT.
Obviously it will not have the plug connector on the wires.
You will need to spice your plugs.
Water proof splices would be preferred.
Perhaps here.
https://us.rs-online.com/product/zf-electronics/0e72-40at/70207616/
 
Yes but if you look at the diagram. Then look at the photos he has removed the center wire. That makes it a no
I think you mean the diagram of the relay?
That confused me for a minute.
The switch is simply shown in the dark lines near each Bosch relay.
In the modified system the switches have the same function as in the original system.
I realize this may not be clear unless the entire system is evaluated and I'm pretty sure there a no mistakes in the print.
The new system just improves the operation of each side by isolating it from the other side and adding better relays (Which could be done even if the old system retained.)
The purpose of each named switch in all cases is to allow current to flow until the headlight bucket reaches it's desired/selected position or "limit". (i.e. "OPEN" or "CLOSED")
This stops the bucket travel in each desired location.
To accomplish this the switch would have to be "closed" until that point is reached and the switch is "activated" by the button being depressed, would it not?
So use the appropriate wire.
Foot note
One of the things I didn't like about the original design is that both motors still have power to them until both switches activate.
I'm sure it was simple and cost effective but it seem like an unnecessarily hard strain on the motors as they never are in synchronized.
Operation is better with dedicated power, I think.


1703160133009.png
 
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