VCCA Home Forums TECHNICAL - GENERAL Electrical - 6 volt '37 6 volt head light switch

Hello Everyone,

Please bear with me if this gets a little long winded.....I am replacing the harness in my '37 MD.
I had put a 7 wire directional switch in the car about 4 years ago when my "Uncle Bill" owned the car.

I removed the instrument panel so I would have easy access to remove the head light switch.

Here is where I need help.....There was a ballast resistor with modern wire attached to the a lead on the backside of the head light switch where the wire for the generator attaches. The lead has an extension with a second screw. The ballast resistor has a wire attached at the second screw and the other wire from the ballast resistor attaches to the body of the head light switch.

I can't be sure if I added it at the time of the install of the directionals or it was there before I added it.

And of course I can not find the install directions which came with the directionals to see if it's something I added. ( There is no brand name on the directional switch )

Any advice/input would be appreciated.

I'm a '35 guy where the light switch used with the three brush generator has a resistor to limit charging until the lights are turned on. While I took my driving test on a '37 I never got under the dash but is this a possible similar situation?

That feature was used n 1934-1937 Masters and in 1937 the Master and Master Deluxe.

Probably.

Thank you all for your input.

Does the wire gauge have any effect on operation of the ballast ?? It currently has 18 gauge wire. I was thinking of upping it to 14 gauge wire while I'm under the dash as that is what the harness appears to be made of.

While I'm in the process of replacing the harness I plan to add ground wires to the following items....heater...defroster....instrument panel.....head lights (which will have relays for both hi and low beam, grounded) .....gas tank (already done). I haven't decided about grounding the rear sockets as that will require soldering which I'm awful at. All of these items will meet at a common ground strip that in turn will be connected to the battery. All of this will be with 14 gauge wire.

The gas tank fill pipe will be grounded to the gas tank which will also be grounded to the chassis with a braided ground wire.

Seems to me like overkill adding all the separate ground wires.

18 Ga. wiring was never used for 6 volt..For general lighting it was 16 Ga.

I tend to think the same also.

Yes, you are all probable right, it is a bit of overkill. But how many posts have been answered with the cause being " a bad ground". ( my gas gauge was one of them. )

A new harness is going in and decided now was the time to eliminate any possibility of a "bad ground" being an issue. I guess this is my way of insuring a sense of reliability.

Yes, grounding can sometimes become a problem and with multiple grounds that should help to eliminate issues. However, if your common ground strip becomes corroded or your negative battery post develops corrosion in the future, you could still have a potential ground problem eventually.

The battery connection I'm not worried about as it will receive a monthly inspection during the driving season once it's back on the road.

As for my ground strip,which is behind the left kick panel, each connection will receive a coating of a copper paste that I use at work for large electrical connections that may be susceptible to moisture.
I used this paste for my ground and power connections on my gas tank sending unit since they are located outside the body.

Each ground point will be treated the same way.

Sounds good! The copper paste should do the trick.

Hey...where can I get some of that copper paste stuff?

Hello Junkyard Dog,

I'll check tomorrow and get a brand name and find out how the company acquires it.

Cool! I can really use some of that stuff.

Hi,
I have just had a Peterson generator conversion done and a new standard cut out switch.

My old cutout has been sent to TFS for diode conversion, and when it is returned I will change the switch over.

My Question:
Regarding the resistor on the back of the light switch, can this now be removed completely now that the charging regulating has been changed and a diode added to make the setup completely solid state???

Peter

Hello Junkyard Dog,

The material is called.........KOPR SHIELD.......It is manufactured by Thomas & Betts.

Cool! Thanks for the information. Now all I have to do is to find out where it is available.

Since there are different types, do you happen to know the T&B catalog number or the part number?

Hello Junkyard Dog,

To be honest, I didn't think to write it down. I'll check all that tomorrow. I apologize for the incomplete info.

Hey, no problem! I have a feeling that this stuff is going to be very expensive.

Everything worth having is expensive but everything expensive isnt always worth having.
Tony

A local auto parts store should be able to get this.

http://www.permatex.com/products-2/...atex--copper-anti-seize-lubricant-detail

That is copper anti-seize for bolt threads and etc. KOPR SHIELD is for electrical connections and improved electrical continuity. I already have anti-seize in stock and it isn't the same stuff.

Hello Junkyard Dog,

The company web site is www.tnb.com. The container is a 1lb. container and I wasn't able to find out what the company paid for it. It does show a catalog # CP16.

One of the guys at work says that Permatex also makes a type of KOPER SHIELD but is distributed in a smaller container.

Thanks Dave and I appreciate you looking into this for me!

Another member has connected me with the Permatex version as well so now I have two to choose from.

Hello Everyone,

I would like to add an up-date to this forum.....I decided I would reread the electrical section of my shop manual and what caught my attention (you know how you have to reread something before it sinks in) was how to check the generator.

It says that one of the checks for a generator not working is to check the resistance on the head light switch. No resistance....no charge.

I went on Google to try and find a value and came across Mark Yeamans response to " '38 Chevy 1/2 Ton Headlight Switch" , 02/2012. (Chevy Trucks)

It appears that my headlight switch is missing the resistor and the ballast resistor was added to take it's place. Which explains why the charging system was always up around 20 amps when driving during the day.

From that forum it appears that the original resistor may not be available. I liked his idea of a variable resistor that could be used to taylor the generator output.

I have never been very good with auto electrical, but this car is teaching me a lot.

The 1937 Master and Master Deluxe used a 1.55 ohm resistor on the back of the light switch. A replacement should be available from an eletronics store.

Hello Chevgene,

Would I be looking for a "modern" resistor or would the wire wrapped mica type originally used still be available ??

It would be modern.

Like Gene I doubt the wire wound mica type would still be available.
I would also use the heavy type modern unit (5 watt) which generally are a 3/8" square section ceramic body.

Tony

Thank you for the info guy's,

I have put that on my Saturday to do list. Right after I cut a bunch of firewood. Starting to get cool here in the northeast.