Dim headlights

[TodFitch]

I checked the factory service manual and the original headlights were 35/45 watt. The later 6006 and H6006 headlights are 40/50 watt. So the newer lamps, incandescent or halogen, are running more current through the old wires than when the car was new. Based on this, I think the recommendation that others have posted on adding headlight relays would be a very, very good idea. Especially if you are not putting a full new wiring harness with wires properly sized for 6v into the car.

[DrDoctor]

   I don’t claim to be an electrical engineer (I’m actually a retired doctor), but I think there’s some confusion about watts v amps.  So, to clarify: When an object's velocity is held constant at one meter per second against a constant opposing force of one newton (the International System of Units derived unit of force), the rate at which work is done is one watt. Wattage (watt) is the rate at which work is done when one ampere (amp) of current flows through an electrical potential difference of one volt. Amperage is the strength of the electrical current. An ohm is the derived base-unit of electrical resistance in a wire, and/or the electrical device being supplied electrical power. Therefore, since the output (illumination) of these sealed beams is greater, but the draw thru the wires serving these sealed beams is actually reduced, based on this, the installation of head light relays isn’t necessary, but it certainly not going to hurt anything, either. Thx.

[Reg Evans]

DrDoctor,

Can you tell us where you purchased these bulbs and possibly a part number ?  I would like to try a set on my 42 Coupe.   I'm tired of being tailgated at night and seeing my cars silhouette on the road ahead of me because of my dim lights.

Thanks,  Reg

 

[DrDoctor]

Reg,

   Sure—I got them at a local independent auto parts store whose owner (a friend of mine) has a Carquest franchise. I’m sitting here looking at the receipt for those sealed beams right now, and the part number is: CLB H6006. The cost when I ordered them (he doesn’t carry them in stock—not much call for 6v components until I got the ’46 Club Coupe) on the 19^th of June, 2015, was $23.⁹⁹, but I didn’t pay that much for them. I’d guess they’d still be in the $20-25 range. If that part number doesn’t work, let me know. I’ll talk to him and get another number (if there is one) for you.

[DrDoctor]

Reg,

   To continue—they also make 6v quartz-halogen light bulbs that will fit in the tail light sockets, but they’re quite expensive (my auto-parts store buddy said that they could go for as much as $35-50 each retail. And, they do put out significantly more heat than a regular bulb. I didn’t even pursue the amperage issue, as I just didn’t want to spend (even with the potential discount) that much money, so I can’t address that. If you do decide to go that route for the tail lights, I’d recommend using the relays as mentioned above, to eliminate putting too much load on the wires supplying those bulbs. It’d be a lot simpler than rewiring that circuit. Just a tho’t . . .

 

[Reg Evans]

18 minutes ago, DrDoctor said:

Reg,

   Sure—I got them at a local independent auto parts store whose owner (a friend of mine) has a Carquest franchise. I’m sitting here looking at the receipt for those sealed beams right now, and the part number is: CLB H6006. The cost when I ordered them (he doesn’t carry them in stock—not much call for 6v components until I got the ’46 Club Coupe) on the 19^th of June, 2015, was $23.⁹⁹, but I didn’t pay that much for them. I’d guess they’d still be in the $20-25 range. If that part number doesn’t work, let me know. I’ll talk to him and get another number (if there is one) for you.

Doc,   is this it ?

https://www.ebay.com/itm/7-Halogen-6V-Glass-Sealed-Beam-Head-Lamp-Headlight-Light-Bulb-6-Volt-New-/253210340283?_trksid=p2385738.m2548.l4275

[DrDoctor]

Reg,

   YES, that appears to be it. TIP: buy an extra one (or two) for spares. Regards . . . .

[Reg Evans]

Okay....gonna do it.  Will report back with my results .  Thanks !

[DrDoctor]

Reg,

   Great!!! I’m looking forward to it, and I know you’ll be pleased with the head lights. Warmest regards . . . .

[cerick305]

I don't want to look into replacing with halogens since I'm trying to get my wattage down.  I'm getting only 3.75 volts at my headlamps (I'm on 6 volt system).  Seems like the ground is fine when I run a test wire from battery.  May need to replace the negative wire to the lights.  Thanks everyone for your help. 

[Plymouthy Adams]

sounds as though you may be in need of a voltage drop test...

[bobostski]

 I bought a set of these bulbs at NAPA. If I remember right it's all they carry. The had to get them from the ware house. I just looked them up and they are listed for $16 each.They are made by Wagner.

[bobostski]

This is the listing from on line... Headlight Bulb - High & Low Beam (Halogen)
Product Line NAPA Lamps	PART # LMP H6006
FITMENT  Complete Vehicle Conditions	WARRANTY   Download
Reserve Online Price (USD) $15.29 /Each Was $16.99 Call Store for Availability. (214) 760-9104 Qty	ROL 10% Off

Edited October 30, 2017 by bobostski
spellin

[TodFitch]

13 hours ago, cerick305 said:

I don't want to look into replacing with halogens since I'm trying to get my wattage down.  I'm getting only 3.75 volts at my headlamps (I'm on 6 volt system).  Seems like the ground is fine when I run a test wire from battery.  May need to replace the negative wire to the lights.  Thanks everyone for your help. 

 

12 hours ago, Plymouthy Adams said:

sounds as though you may be in need of a voltage drop test...

I agree with Plymouthy Adams here. You should have at least 6v at the headlamps. At 3.75 your lights will be very, very dim and swapping out to quartz-halogen will not fix the issue. The quartz-halogen will try to draw the same power as your existing incandescent and you will still have a 6v lamp trying to do its job on less than 4v.

The filament resistance of an incandescent or quartz-halogen bulb varies with temperature. As it gets hotter (brighter/whiter) the resistance goes up. But if we simplify things and assume filament resistance is constant, then with power = voltage squared divided by resistance we can compare the power your lights are putting out compared to what they should be:

P at 6v = 6*6/R

P at 4v = 4*4/R

Ratio 4v/6v = 4*4/6*6 = 16/36 = 0.44 = 44%

So you are losing around half your lighting. A quartz-halogen bulb typically puts out about 40% more light for the same wattage, so just swapping those in will still leave you with less light than you would have with a good electrical system and the stock bulbs.

To do a voltage drop test, put one end of your voltmeter on a good ground then with the other lead check the voltage at various places in the circuit until you isolate the area(s) that show any measurable drop. You may also find some considerable heat generation at those places. If you have the original wiring and switches there will probably be a lot of places that need attention. You may also find resistance on the ground return too especially if you have new paint or old rust.

If you don't feel like rewiring the entire car and refurbishing/replacing the switches, etc. then the other suggestion of running new wires to relays located close to the lights and running the relays off the existing circuitry could be easier.

[Plymouthy Adams]

there are plenty of website that would be wise to peruse when testing for voltage drops but this is quick and easy explanation for the why and how of such things happen in an electrical system that create less than adequate voltage and how to use your average meter to test, locate and repair

https://www.engine-light-help.com/voltage-drop.html

Edited October 30, 2017 by Plymouthy Adams
fat fingered this entry to hang and back

[cerick305]

From doing voltage drop test I think the problem my be in the main light switch.  Plus when moving the switch around, items turn on and off on their own.  But I don't think all the problem is in the switch, seems I am losing to much through the headlight beam switch also.  I haven't taken it apart yet.  Anyone know where I can get a new Main Light Switch for a P15 1947 special deluxe?

[Plymouthy Adams]

I would suggest to use the headlight switch to turn on a direct linked and fuse feed from the battery through a relay to the headlight dimmer switch from there it will feed the high and or low beam as selected.  The dimmer switch is of a style that self cleans with use.....cycle the switch a number of times and then check your connect/voltage drop.

[cerick305]

2 minutes ago, Plymouthy Adams said:

I would suggest to use the headlight switch to turn on a direct linked and fuse feed from the battery through a relay to the headlight dimmer switch from there it will feed the high and or low beam as selected.  The dimmer switch is of a style that self cleans with use.....cycle the switch a number of times and then check your connect/voltage drop.

I will try that first, but also getting alot of heat from the main light switch

 

[Plymouthy Adams]

the heat is due to the fact you still drawing current to power the head lamps through the somewhat worn contacts....the relay will not require such a load and should be able to do the switching to the relay without any generation of heat.

[Reg Evans]

On ‎10‎/‎21‎/‎2017 at 4:39 PM, Reg Evans said:

Okay....gonna do it.  Will report back with my results .  Thanks !

Well I got the new bulbs and plugged one in.  It's not as bright as the conventional bulb.  I checked the voltage at the bulb connection and it was only 4.5 volts so I'll be replacing the headlight switch and high/low switch next. 

If that doesn't improve the brightness I have some relays waiting.

[Frank Elder]

On 10/19/2017 at 6:42 AM, Sharps40 said:

This is essentially your schematic, two or four bulbs, doesn't matter, wiring is the same.  Wire gauge as you see fit, heavy is good.  5 wire relay or 4 wire relay, doesn't matter, wiring is the same.  Too simple? (And now you can do this and ignore any post that says "go buy a repair manual"!    )

 

 

Can this system be adapted to use for the turn signals and brake lite?

 

[greg g]

Check voltage going into, and coming out of the dimmer switch.  I would guess it is the most likely the source of resistance causing low voltage at the fixture. Even the new bulbs on high beam are only drawing less than 10 amps each.

[Plymouthy Adams]

you only need one relay if you put it between battery and the dimmer switch..the headlight switch will turn on the relay, the dimmer switch will then direct the voltage to high/low as selected by yourself/driving need.  Cut the wire from the headlight switch to the dimmer connect from headlight switch to relay coil one side, ground other side by additional wire.   Run new wire from battery source through inline fuse holder then to wire you cut from  headlight switch to relay switch contact one side as input and the other contact side to dimmer switch input,,,,let the big dog eat.

[LazyK]

11 hours ago, Frank Elder said:

Can this system be adapted to use for the turn signals and brake lite?

 

no reason to. Tail lights and turn signals are low wattage/amp draw in comparison to the head lights.

[cerick305]

I am only getting 4-4.5 volts from generator. I test this with engine running and generator disconnected from battery. I assume generator should be at 6 volts when no load is on it......?   

Through votag drop test, I'm getting a pretty consistent small voltage drop through components up to the headlights. Makes me think nothing abnormal with the voltage loss.