1941 Dim Tail Lights

[John R. Hess]

Hi everyone,

 

We have been plagued with dim tail lights and rear turn signals, which we feel is unsafe.  The correct bulbs are in the sockets and the grounds have been tested as good. 

 

The first thing I have done is to dissemble the tail light assemblies in order to replace the red outer lenses.  My concern is that the inner "focusing lenses" appear to be darkening in varying degrees, possibly restricting the light output (see photo).

 

Does anybody know if these internal lenses should be clear or near-clear.  For comparison in the photo there is a reproduction front focusing lens.  All the rear ones are much darker in various degrees than the front reproduction.

 

Does anyone know if there are new reproduction internal lenses for the rear.  There are two on each side.

 

 

[EmTee]

Are the lenses glass?

[John R. Hess]

1 hour ago, EmTee said:

Are the lenses glass?

They are plastic, probably that soybean-based plastic.

[Jim Nelson]

Make sure the ground wires are good and tight.   Then the same for the feed wires.   You might see what voltage is at the light when  its 'on'.      Same at the battery when it's under load.   I would make sure the engine is running around 2000 rpm to give you the generator full output.      After that,   Make sure the lenses are 'clean' for maximum output.   

[neil morse]

I have a few suggestions based on what I did with my '41.

 

First, with regard to the tint of the internal lenses, it's hard to tell from photographs whether yours are darker than the ones on my car.  If you click on the link below, you can see some photos of the internal lenses on my car for comparison.  (Click on the arrow in the upper right hand corner to get to the right post.)

 

Second, I highly recommend that you switch to LED bulbs.  You will see in my thread that I originally went to halogen bulbs.  But I became concerned about the extreme heat that these bulbs generate, and I didn't want to melt the plastic lenses.  So I went to LED bulbs instead.  These are readily available in 6 volt sizes, including the dual filament ones that you will need for the brake lights (as well as the front parking/turn signal lights).  I'm sorry that I'm traveling now so I don't have access to the information that I need to give you a link to the supplier that I used.  But maybe someone else can chime in here.  The LED bulbs are significantly brighter, which is indeed a safety issue in today's world where other drivers are used to seeing much larger tail/brake lights on the car in front of them.  They also use hardly any current and are much more efficient than the original incandescent bulbs.  (Also, by the way, they make a huge difference when substituted for incandescent bulbs behind the dash to illuminate the gauges.)

 

But I also agree that you should check the voltage, the integrity of the connections at the socket, etc. as others have recommended.

 

Good luck!

[Marty Roth]

51 minutes ago, neil morse said:

I have a few suggestions based on what I did with my '41.

 

First, with regard to the tint of the internal lenses, it's hard to tell from photographs whether yours are darker than the ones on my car.  If you click on the link below, you can see some photos of the internal lenses on my car for comparison.  (Click on the arrow in the upper right hand corner to get to the right post.)

 

Second, I highly recommend that you switch to LED bulbs.   

 

Another option, which I've done to my vintage 1954 U-Haul trailer, is to paint the interior of the taillight bucket, either gloss white, or a reflective white.

I've also improved the lights on another old car by lining the interior of the bucket with Aluminum Foil for great reflection

[RiKi5156B]

I sprayed mine with white and it really made a difference for such small light housings.

[Larry Schramm]

How did you test the grounds?  If you did just an ohm check for continuity,  you may show a ground, but not a good ground.

 

The best way to check a ground for ability to handle current is to connect one side of a headlight bulb to the ground at the tail light connector and the other side directly to the battery.  The headlight should shine bright.  If not, you have the possibility of only two or three strands of a multi-strand wire connected and the rest of the strands broken and not making contact.

 

An additional test while having the headlight connected is to connect the negative wire of a volt meter to the negative battery cable.  Then with the positive lead see what the voltage is on both sides of the headlight bulb.  On the positive side of headlight, there should be battery voltage ( 6 or 12 volts depending on vehicle).  On the ground side you should have maybe .1 or .2 Volts.  If you have much more than that you have a bad ground circuit.