What is this
 

My 300D saw it's first rain today. I opened the trunk and found some water. The best I can figure it must be the rear window seal, it didn't seem to be coming from the trunk seal. While I was looking around for the source of the leak I pulled the plastic shroud/covering off the side by the radio antenna and noticed this hanging there. It looks like it would carry air as the end is threaded, and you can screw it on something. It has a little push valve in the center of it, at least that's what it looks like. Kind of like a bicycle tire pump attachment that screws on.
What is this thing :confused:
I have attached a couple pics. Thanks for your help.

Connector for a cell phone or VHF radio antenna? Attachment for a hidden huka pipe?

Check also the tail light seal as a source of leaks into the trunk.

Sixto
95 S420
87 300SDL

I'm starting to feel like an idiot :o - maybe it is for a previously installed electrical device. I just assumed with all the vacuum lines everywhere it was some neat thing I hadn't yet read about in this forum. I'll have to look really close and see if I can find where it goes. Thing is that the car looks totally stock, like nothing extra has ever been installed anywhere.

In regards to the tail light seal suggestion - there is a couple of very small streams weeping down from there, but the main amount of water is falling from up by the driver's side trunk hinge. It must be the window seal, because the only other thing could be the trunk seal and I could find no evidence of water getting past that seal. The strage thing is the rubber around the rear window looks good, no age cracks and not too hard.

Now, about that hidden huka pipe ;) way too long ago for me my friend :)

The painful statistic is that most trunk leaks result from a brittle rear window seal.

79 300D? That would be CB radio antenna, not cell phone antenna :)

Sixto
95 S420
87 300SDL

I have that same little thing laying in my trunk too, I have always wondered what it does or what its for....is it really an antenna attachment of some sort? Or does it serve some other purpose, it sure looks like an air valve fitting.....

looks like antenna wire of sme kind

Drains !!!
 

My trunk also was full of water. I bought a new trunk seal to fix the problem. Then some genius on the forum suggested I check my drains on the underside of the car. I used a coat hanger and stuck it inside EVERY drain on the car. Water gushed out!!! I had a clogged drain. The drains are quarter sized plastic plug/holes, you can't miss them. They clog with leaves, sand, or whatever else can fit in them. Save the time and money, check your drains before you buy ANYTHING !!!! :eek:

Factory installed
 

connector for a cell phone was stock equipment.
The dealer need only install the hand set, converter and antenna stub.
On my 1985 300SD the wire and converter where factory stock.

Thanks - I knew someone would have a logical explanation. Cell phone in '79 :confused: Wow, I wonder how much they paid for minutes back then :D

In regards to the water - thanks for the suggestion to check the drain holes. I have been under the car many times and seen them. They look clean, but maybe there is debris up inside where I can't see. I will stick a wire/coat hanger in a few of them to see what happens. Now would be a good time since if they were clogged there should still be some water in them.

My 240D has the connector also, and I was think about trying to use it. I seem to remember mine as connecting to and using the radio antenna instead of seperate antenna. I olny looked at the once and it was just a quick look, so I can't be positive.

Just two little problems with that theory:

1. Cell phones did not even exist in 1979

2. I own a '79 300D and there is no such connection in my car.

Both my 300D and the 450SL have the cable, the other end is coiled up in the dash behind the glove box area. Always wondered what it was for, a CB sounds more like the era then a cell phone.

There was a mobile phone that was around in 50's through to the early 90's that was replaced by the cell phone of today. I can remember my uncle using his in the '60's, and a friend that I went to school with had one as late as '93 before switching to a cell phone. They had a hand set that looked like a regular phone. There was a detective show in the 70's with William Conrad that the detective had in his Lincoln MK IV.

Ahhhhh....but the point is...the drains being clogged have little meaning if you don't have a leak somewhere...

Mine is the taillight assembly. I had 3 inches in there this morning.

As a telephone technician for a long distance company back in the early 90's, I went to all of the radio towers for one of our customers (got a really interesting tour of Texas ranchland from the panhandle to the Mexican border). These big clunkers were huge in the vehicles....and no roaming ! ! :p