Author Topic: Humid/Wet drivers footwel  (Read 635 times)


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Humid/Wet drivers footwel
« on: 10 September 2017, 07:07 PM »
So as i was cleaning the car i found some dampness underneath the floor mat -

Took out the floor carpet and saw that the sound deadening material had some water - which could be pushed out through the cracks on the top

So i removed the center console so that i could get to the sound deadening material and found that there was no damage to the floors - actually overall they all look great

I think the water came from the AC drains - as i felt some of it this summer as i was driving around - the drains were blown out but after a few drives the water was again dripping inside. I will try again but need a lift to get to those spouts -

So what should i do? can you get the sound deadening material? Should i replace it with something more modern ? ( I usually try and keep it original) Any ideas ? As you can see in the picture above to pull it i guess i would need to take the gas pedal out as well, as it is around it (or cute the mat). So i stopped there.

I would say its not a consistent issue as there is no damage but needs to be dealt with ...

Any ideas are welcome at this point is a 1974 450SEL US version

Thanks in advance ..

Diesel 617

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Re: Humid/Wet drivers footwel
« Reply #1 on: 10 September 2017, 07:49 PM »
Most common places for the leak are windshield seal (each corner) and the door seals. Try blasting the windshield corners with water from a hose (good pressure) and you'll find out real quick if it leaks from there. It's not uncommon for new seals to leak (tricky to install/poor rubber). If it is the seal head to autoparts store and pick up a tube of clear silicone sealant, peal back the seal where it meats the windshield and fill in the gap in. Go up the windshield at least half way and about a foot on the bottom, towards the center.

Otherwise run the heater at full blast and check your coolant level, if that goes down then you;d be in for a heater core. but check the windshield seal first, most likely culprit.
X3 1980 300SD Blown Heads, trans -Retired
1980 450SEL Parted out/Scrap
1980 450SEL to Diesel Parted Out/Scrap
1979 280SE Euro Spec Cloth Seats Sold
1979 300CD Daily Driver - Sold

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Re: Humid/Wet drivers footwel
« Reply #2 on: 10 September 2017, 08:49 PM »
Congrats on having such nice floor pans!  You are extremely lucky as most 116s have rusty floor pans due to leaks.
Check the grommet for the hood release cable and area behind and below the fuse box. Well documented poor design has lead to this area rotted out and expanding as rust holes in the firewall. Water will pool in the driver side then run back if the car is at an upwards angle.
Check sunroof drains are running clear.
Also make sure your fresh air intake is clear of crud under the chome grille.
Also check windshield wiper motor grommet into the firewall.
Chase and kill that rust devil ;D
1977 450 SEL 6.9 - Astralsilber