Tail Light bulbs - holder

[Bonnyboy]

I had a brake light stop working on the passenger side so I undid my bulb holder and tried to pull it out of the tail light housing. The backup light bulb didn't want to come out of the housing as the glass portion of the bulb was larger than the opening.    The holder says it should be a 21W 32cp  same as the marker and brake light but the opening in the tail light housing is smaller than the bulb in that location. 

I had to break the bulb and vacuum the pieces out to get at the brake light bulb. 

Our technical manual shows a larger bulb for the backup light (same size as marker and brake light) but I can't see any way it got in there from behind.

Am I missing a secret means of removal. 

[66andBlue]

....
Our technical manual shows a larger bulb for the backup light (same size as marker and brake light) but I can't see any way it got in there from behind.
Am I missing a secret means of removal. 

Not sure I follow you. Brake (stop) light bulb and turn signal  bulb are 21W, back-up bulb is 15W why would the latter have a larger bulb diameter?
https://www.sl113.org/wiki/Electrical/TailLights?action=download&upname=Tail_Light_280SL.jpg

[rwmastel]

The holder says it should be a 21W 32cp  same as the marker and brake light but ...

What is 32cp?

[Cees Klumper]

32cp seems to be a type of bulb base.
That bulb must have been installed originally with the taillight lense off? And according to Alfred, the proper bulb us different from the one indicated on the holder (which makes sense given the opening is too small for that size bulb).

[DavidAPease]

I think "cp" must stand for "candle power" (also called "candela"), a measurement of light output used long before we start using lumens.

For example, I've seen a dual-filament taillight bulb described as "21W/5W 32/3CP", so 21 or 5 watts, 32 or 3 candlepower.

For the technically inclined, the two measurements are not convertible (unlike our cars), due to lumens measuring total light output but candlepower measuring directional light at the brightest point.

         -David

[kampala]

Bonneyboy

I recently put all new bulbs in the 280 rear lights.  No trick.  I replaced all with same as listed in the tech manual - all just fit and assembled without issue.  Away from the 280, so can’t post photos.

[114015]

Yes, Aslam,

That's useful.

After 20 or so years it is very wise to replace all the (old) bulbs.
Many of these have turned dark even if they still work.
This  is especially important with the older style "all red" taillights which have lower wattage bulbs anyway.


Much brighter with new (quality) bulbs.
Cleaning out the taillights from the inside also helps a lot !


Always remember, especially taillight is a safety measure for other traffic participants to better see you!


Best,
Achim