Jump to content

Purpose of Cowl Lights - DB 26 Coupe


Guest scliim
 Share

Recommended Posts

First of all... just want to say thanks for all the advice I've recieved from this forum. I've learned so much so quickly...and hope to be able to offer more as I gain experience.....

My DB '26 Coupe has cowl lights, though they seem to be loose and are pointing in disparate angles...

What was the purpose of these lights? Where should they be pointing? Any feedback would be helpful.

The original owner disconnected the head lights, cowl lights, and the break light as he didn't want to burn out the bulbs.

I've got the wiring diagrams now, but it doesn't show the connections for the cowl lights or where they connect behind the switch.

When I look behind the dash, I only see a single long wire going across connecting the two cowl lights from left to right. In the middle of that wire, a small piece of the fabric sheathing is removed and it's bent as if it must have been connected to one of the posts at one time.

Regarding the headlamps and break light, still looking to find time to map the dangling wires and get them reconnected according to the diagram.

Link to comment
Share on other sites

An excellent question, as cowl lights seem pretty useless on the surface of it...........

I've always considered them "parking" lights, so that if you park on a busy street someone could see the car was there as you ran into a store.

Also, they may have some use for night breakdowns, as they would shine some light toward the engine area.

Would they also help you see your fenders, for night time driving and parking?

They should be pointed forward, of course.

Link to comment
Share on other sites

Alot of people convert there cowl lights to turn signals which I think is a great idea if you plan to do alot of driving. The single wire deal under the dash and connected in the middle sounds original as this is how my own car is wired as well.

Link to comment
Share on other sites

Thanks for the feedback. Now which post would I attach it to on the back-side of the ingition switch (on the backside of the dash) ? ...and once connected will these lights come on only when I have the headlights on, or do they alternate...i.e. if the cowl lights are on, the headlights are off etc.?

I think I need to complete the basics of just getting things turned back on and functioning before I go with the turn signals... but it sounds like a great idea. If you have plans or instructions I'd greatly appreciate it.

I'm more concerned with brain-dead folks coming up from behind while driving too fast. Here we have a lot of small hills, narrow roads, and no shoulders. So have been contemplating some type of blinking hazard lights or more visible brake lights on the back to get folk's attention. Any ideas around that?

(Note: while out driving my car I seem to find two kinds of folks. The ones who want to pull up along side and chat while driving, and those who are lost in their own little world not even realizing that an historic vehicle is in their presence... :rolleyes: )

Link to comment
Share on other sites

Guest DodgeKCL

I dont' know when the law stopped but many areas required lights to be on a vehicle if it was parked after dark on a road. I believe it went on through the 20s,30s and 40s but dont' know when it quit. I think cowl lights which lit up aong with the licence light were used to comply with this law.

Link to comment
Share on other sites

I dont own a 26 so I cant be of much help with a iring diagram, do you have a book of information, I might have one for your car, it may have the wiring diagram within that.

Good idea on just gettin er going first.

Link to comment
Share on other sites

Yeah...I've got a wiring diagram for this model (DB Mechanics Instruction Manual 1914-1927).

It shows all but no information regarding the Cowl lights at all... I've searched the web and I find nothing that even refers to them....except the items 'for sale'.

Link to comment
Share on other sites

OK.... so I replaced my fan belt (see other thread), and everything was going great. I don't really know what I did but I got the headlights working but not the Cowl Lights. hmmm

I worked forever trying to figure out the break light only to find that there aren't any bulbs in the sockets....plus to make maters worse, the break light bulb socket doesn't seem to be completed and is a bit rusted. The socket for the light that illuminates the license plate seems to be in tact however am not sure what bulb goes there. I have some work to do.

Now back to the headlamps... the guy I bought the car from, disconnected the headlamps and cowl lights back in 1988 so as not to burn out the bulbs... My son (14) and I go the headlights working at about 9:00pm. We were so excited (head lights, and a working fan belt)...that we backed her out of the garage in pitch dark and went for a night ride though the neighborhood. With beams glowing bright, we toured the neighborhood Christmas lights having a wonderful time...until we got back to my drive way. Along the way we were noticing that every time we hit a bump the lights would glow brighter or flicker.... then when I bumped over the curb to come up the driveway the lights went out one after the other.

After getting the car in the garage I took the lens caps off the lights and found the bulbs to be burned out. (the filament was gone in both bulbs)...so I burned out the bulbs that the previous owner had worked so hard to preserve. My guess is that these bulbs were about worn out anyway...but now I'm searching for new bulbs.

Currently looking for 'GE 1143 32c 12-16v' bulbs with the two little pegs on the post. Next need to continue to figure out how to get the Cowl Lights working.

How to open the light casing on the cowl lights to check the bulbs?

Also, any ideas on replacing the internals of the break light as it seems pretty rusted. Plus the red lens is cracked and chipped which you don't see till you take off the cover. Would it be easier to replace the whole thing? Where do I find the Tail Light assembly?

Link to comment
Share on other sites

The cowl lights and tail light should work in the "park" position on the headlight switch. Cowl lights will be off when the headlights are on. In the tailight housing the bottom bulb is the taillight and the upper is brake. Sounds like your generator is not regulated and is the voltage is too high, blowing the bulbs. You may also have a short somewhere is the lights go off and on when hitting bumps. What does your amp gauge say? There is a reason they are blowing.

Link to comment
Share on other sites

I agree on the bulbs, even being old they prob should not have burned out the way you describe, you have too much current going to them.

Link to comment
Share on other sites

It was dark so couldn't read the gauges...and didn't think to look either. Just to clarify the lights didn't actually turn on and off when hitting bumps...but would glow brighter or dimmer for just a second and then be fine...it was when we went up into the driveway that the one went out and the other went shortly after..

So this at least gives my son and I more things to explore and test out before we put in new bulbs as they seem very hard to find. Searched for hours yesterday evening on the web and only found sites describing them...but could not find them for sale. Is ebay a safe source for these kinds of lightbulbs?

It was a great ride though... the illumination from the lights cast a different light on things as we went along... It reminded me of those scenes of John Walton in the 'Home Coming', where he was driving is old truck home in the night in that snow storm...(but we didn't have snow...)

Link to comment
Share on other sites

Hitting bumps and the lights growing brighter or dimmer still indicates an electrical problem ( as I am sure you have guessed ) that will be related to overcharging of the bulbs themselves.Good luck

Link to comment
Share on other sites

Guest DodgeKCL

Luckily I have a box of Mazda 1000s (32cp/32cp) for middle 30s headlights but 1129s (21cp) which are the parking lamp/running lamp in the top of the headlight reflector in Dodges and Plymouths have JUST gone out of sale in Canada. Be warned. Even NAPA and CarQuest no longer have them and they did last year. They had GE blister packs of 2. No longer. And they can't get them.

Bulbs are self regulating as far as current goes. The reason a bulb will glow bright or dim only has to do with the level of voltage on it. However it IS too much current going through them that blows them but that is the result of too high a voltage on them. Our old car's 6/12 volt buss system was regulated by the battery. It was the battery that kept the system at 6/12 volts. The generators,6 or 12 volts, will output some 20 odd volts if disconnected from the battery. If the battery is even momentarily disconnected from a running car,all the light bulbs that are turned on at that moment will blow. (Don't believe me. If you have a battery safety disconnect switch on your car, start your car and turn on all your lights and then switch off the battery switch. There will be this huge 'flash bulb' flash as all the bulbs open up.)

I think your generator is OK. I think somehow the battery is becoming disconnected from the buss and the voltage is spiking and poping the bulbs. Check both battery cables and any line that brings the battery onto the buss under the dash. The grounds at the bulbs won't matter as any problem there would just serve to make the light blink on and off. Same with the feed wire from the switch. The opposite of the battery coming off the buss is the generator dropping off and that will only dim your lights slightly as the buss drops to the battery terminal voltage which is around 6 volts. The running buss voltage is 7-8 volts (or 14-14.5 volts for 12 volt systems).

Edited by DodgeKCL (see edit history)
Link to comment
Share on other sites

Yes.. I was running a 12 V starter / generator on the bench here after I rebuilt it. I was spinning it at 5000 RPM to simulate about 50 mph.. I had a voltmeter hooked to the output and when I disc. the battery for a moment the voltage rose to 62 Volts DC. I could hear the motor lug down. I also think this could probly ruin a ignition coil also..

I suppose a intermittent open circuit in one of the battery cells would also cause this to happen..

Link to comment
Share on other sites

So this at least gives my son and I more things to explore and test out before we put in new bulbs as they seem very hard to find. Searched for hours yesterday evening on the web and only found sites describing them...but could not find them for sale.

You might check with Restoration Supply Co. I've ordered all of my replacement bulbs through them. Make sure you order the right style of connector pins: straight or offset, as well as number of filaments, voltage, candlepower (or wattage) you need for each application.

You can download their catalog off their site: Restoration Supply Company

Link to comment
Share on other sites

Do you still have the original generator setup on that car and if so is it a "third brush" regulated generator? That would be typical of the era.

One problem with that type of setup is that the generator acts as a constant current device. They rely on the battery keeping the voltage from going too high. A classic failure mode with a bad ground path between the battery and the generator is too high a voltage that burns out light bulbs.

Because the brightness of your lights changed as you went over some bumps and apparent high voltage burning out the lights, I strongly suspect that you have a ground circuit (generator->engine, engine->frame, engine->battery or frame->battery) that is not properly electrically bonded.

Link to comment
Share on other sites

Guest Backyardmechanic

When one frist starts up a engine on these old cars/truck after replace any electric comp.such as battery,starter, generator the system should always be polized,By doing this after all is connected before starting/or even turning over the engien with the starter 'with a peice of wire make contact with the generator post and a ground such as the engine block this will make a spark. your electric system is now polised. If this isn't done one takes a chance of burning out the armuture in the generator Or like you did burn out the bulbs.

Vern.

Link to comment
Share on other sites

The one thing I found with my lights not working correctly was that the associated light bulb receptacle was not grounded well to the frame. After cleaning all metal interfaces between the light bulb receptacle and frame the lights worked well again!

Link to comment
Share on other sites

Guest DodgeKCL

Vern If I read your post correctly you've got it backwards. To polarize a generator you take a wire and connect the generator armature output post to the battery for a moment to set the magnetic polarity of the metal in the generator. For most of our cars this would set the polarity to positive ground. If the generator is moved to a negative ground vehicle, this procedure HAS to be done again BEFORE starting the engine, as Vern says. You will cook the generator in about 30 seconds on a running engine if you don't maintain the correct polarization of your generator. However if the generator has not been out of the vehicle ,and the battery polarity has not been flipped around, you do not have to polarize your generator on a regular basis.

Link to comment
Share on other sites

Guest Backyardmechanic

After reading my post you are correct.Hope I didn't cause any poblems with this post.Thanks for setting the record stright.

Vern

Link to comment
Share on other sites

  • 2 weeks later...

Wow...this discussion really makes you step back and see what we take for granted in driving our modern cars. On the other hand, what a fantastic collection of information is being brought forward for our future generations. I fear that our future generations are getting so far ahead of the basics that if they loose what they have, they lack the foundations of where it all started from. Every time I open the hood, or loosen a bold my sons are with me and we explore together the simplicity and complexity of the beautiful old technology in front of us.

Link to comment
Share on other sites

Dave, responding to your post regarding the cowl lights working in the 'park' position. where is this on the switch? On the dash I can turn the dial to the left from center and I get dim headlights, or I turn the switch to the right and get bright lights... is the 'park' position to the Left? If so, this will help me identify which post i need to reconnect the wire to behind the dash.

Also looking to figure out how to open my little cowl lights to check the bulbs. there is a little screw underneith by the post but can't easily reach it with a screw driver.

Link to comment
Share on other sites

Guest DBAcadia

scliim, you will need the 4 position switch to use the cowl lights properly. If you find two let me know as I need one, '24-'26 which is the smaller diameter, not'27 which is larger diameter and won't fit. Any of these out there, Brothers?

Link to comment
Share on other sites

Hmmm... still confused about where I need to be reconnecting the cowl lights (behind the dash board). My assumption is that these came with the car but the wire's been disconnected. So am just trying to figure out how to put it back.

Would the car have come with Cowl lights and not a proper switch to operate them?...or do I simply connect it to the post with the headlights and run them on while the head lights are on.

I still haven't figured out how to open the cowl lights (don't want to bust something), in order to check the bulbs.

Link to comment
Share on other sites

My guess would be that some previous owner replaced a bad 4 point switch with a 3 point. I don't see any harm if you wire it so they come on with the headlights. The cowl lights on mine were a bugger to open. Even though they didn't appear to have any rust, it was there between the lens retainer ring and the can. There is one screw in the lens retainer ring you must remove (I'm sure you did already), then spray them liberally with WD-40 or Liquid Wrench, etc. and soak for a few days. The cowl lights have three small pins attached to the inside of the trim ring. They slide into three slots located on the housing. Then, Turn the trim ring counter clock wise about an inch. The two pieces should release.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...