Techs: Cat converter, trans, or just carpeting???

[JCE]

I had a wierd, sticky stain appear at 3 places on the trans tunnel carpet on the front passenger side of my 300E. The upholstery shop I went to started cleaning it, but found that it was wicking through from the carpet back and just got larger and stickier the more they cleaned. They removed the panel and found the glue was a sticky mess, and they have to order new German carpet to re-cover the panel. They also said they had never seen this happen on an MB before.

Is it possible the trans or the cat converter are acting up and heating the side of the center tunnel, enough to break down the glue? Where should I begin checking for causes? It doesn't seem too likely that after 15 years the glue spontaneously decided to break down and turn into a liquid!

[engatwork]

hmmmmm - something doesn't sound right here John. I would try to get the car on a lift and perform a good visual inspection. If nothing shows up with that then pull out an infrared thermometer and look around with that.

[mbshop]

i have seen this same thing on several mb's. no rime or reason. the glue was coming through even in areas that would not be
affected by heat. asked my dealer and they said that they had seen it also but had no clue. its only on a few cars so who i doubt
that they will waste time on it.

[JCE]

I hope it is just the glue coming through - I'm not anxious for trans or cat work. It just seems strange that the carpet has been stable since the family bought the car in 87, and now decided to ooze glue! Wierd.

[Larry Delor]

What color is the goo?

I haven't had any come through my carpeting, but, one day while digging under the dash, I decided to take apart an electrical connector, and found it covered in a sticky goo. It had the consistency of thick honey, and was close to yellow oxide in color.

Goo, will eventually work its way down from wherever it is coming from. What I mean, is it could be coming from someplace higher up, and it just took several years to work its way down.

Good luck!

-Larry

[JCE]

Larry:

That sounds like the stuff - about half way between axle grease and sun warmed chewing gum. Sort of yellow-beige color. It is mostly found sandwiched between the fiberboard backing and the carpeting glued to the front of the fiberboard, and seeping through the carpet in 3 spots, and all along the bottom of the carpet section where it meets the floor board. It flowed over some cable ties and electric wires on the firewall that were below where a flap of the carpet was glued to the firewall behind the plastic foot shield. It is also pooled along the bottom edge of the trans tunnel where that tunnel carpet meets the floor carpeting. It is still tacky, and has actually flowed into the snap grommet where the carpet attaches to the floor by the seat, and under the rubber floor insulation pad in places.

I didn't see any on the utility side of the fiberboard, just the carpet side. The upholstery shop said it was old adhesive. That sort of make sense, because I don't see it up under the dash anywhere, just up where the carpet side piece was attached to the firewall and along the joint where the bottom of the carpet panel meets the floor carpeting. I will take some pics with the digital and post them tomorrow. Thanks for the info!

Now If I can just find out why just that one section of carpet - the drivers side is fine! Thanks for everyones help on this.

[JCE]

Well, the cat and trans checked out OK - my tech said he has seen this a couple times before over the years. He feels that occasional batches of the glue break down with time. Anyway, here is what it looks like:

Pooled into the carpet snap next to the trans tunnel.


Trickled down along the base of the tunnel, still with red carpet fibers attached.


Running down the firewall (plastic firewall shield and rubber insulation floor bad have been removed)


This shows it is from the carpet: The elongated tear drop shaped patch on the firewall is where that section of carpet was glued, and is sticky like the glue. The glue has pooled along the lower edge of the teardrop, and run down the firewall. No glue is above the sticky patch or found under the dash anywhere else that I could see.

[400E]

One thing I wondered: Could there be a heat shield which has fallen off and allowed heat from tranny or exhaust system to melt the glue?

[JCE]

My tech checked on that (and I looked at another 300E that was on an adjacent rack ) and said everything was there - I suspected heat originally, because I couldn't see the glue just instantly turning to liquid. However, the carpet shop said they have seen in in other cars, and my tech said he has seen a couple of MBs with this. The carpet shop said it had probably been degrading slowly for at least a year, and was just now noticed because it soaked through the carpet.

Also, I usually tuck my daytimer against the passenger center tunnel when I drive. In the C230, my folder turns into a lap warmer in short order, but I haven't ever felt any warmth on the folder from the 300E - just stickiness from the glue! So I guess it is just old chemistry!

[Larry Delor]

Perhaps hot air from when you have the heat on?