How does this water get in??? - PeachParts Mercedes-Benz Forum

JHZR2 · #1 04-21-2007, 10:58 PM

Hi,

Havent heard back from the PO, and after driving the car again today, I think Ill be fixing its rust. It is a really nice and nice driving car - everything is like new, xcept for the non working AC which I knew about previously.

Anyway, I gave the car a thurough soaking test with the hose. a LOT of water directed into all the drain areas, etc., to test them, check for water coming into the cabin, etc.

The main place that I note that water makes its way in is somehow in the driver's side footwell. Fortunately no real rust has formed in the floorboards, but there is a rust spot in the wheelwell that I had found and disclosed previously.

Here is the spot in the wheelwell:

I prodded and scraped very hard around it, and what is shown is where the crackling and rust stops. Now, this is related to some water that comes in... here:

and here:

It sits under the permanently attached sound deadening in the driver's footwell:

The back side of the hole in the wheelwell that I just showed looks like:

The steel all around is strong, and pressing hard from that side does nt crinkle or crumple. But, the water comes in and sits between the firewall and the floor pan.

Everything else is OK:

Though the fusebox seal is broken at the bottom:

But I srayed the car with the hood closed, the water would not ingress through the bottom of the fusebox.

I checked all the drains. Since there is no drain picture thread, Ill post those pics in another thread. So, how would I get water down there in the driver's side footwell, along the black plastic item that covers the vacuum lines???

Thanks!!!!

JMH

JHZR2 · #2 04-21-2007, 11:00 PM

The wndshield seal is old but not terrible - still a bit soft:

JHZR2 · #3 04-21-2007, 11:15 PM

holthoff · #4 04-21-2007, 11:27 PM

Could be rust hole(s) around the hood hinge area. That's a pretty common spot.

JHZR2 · #5 04-21-2007, 11:31 PM

Ive checked around thoroughly, no signs.

Would seepage behind the windshield seal end up back there and in those areas?

Thanks!!

JMH

Larry Delor · #6 04-21-2007, 11:42 PM

Check the front left sunroof drain.
Open the roof, and with a good flashlight, take a look; maybe pour a little water into that area and see where it drains to. If it is leaking, it could be running behind the trim piece and down on to the floor.

JHZR2 · #7 04-21-2007, 11:44 PM

I checked those drains when I cleaned them out on Thursday.

They both are working to let wire go through.
Do you think they might be continuous but cracked inside such that water leaks from them inside anyway?
If so, how would one fix such a thing?

Thanks!

JMH

JimmyL · #8 04-22-2007, 12:15 AM

It is the windshield seal I bet. My wagon does it pretty badly. Actually, so does the Squash.
It is hard to believe such once-high end cars have so many repetitive "known" problems.....

JHZR2 · #9 04-22-2007, 12:17 AM

I agree... The trunks in these cars do it bad too - heavy rains yield water dripping on either side.

JMH

Larry Delor · #10 04-22-2007, 07:57 AM

Quote:

Originally Posted by JHZR2

Do you think they might be continuous but cracked inside such that water leaks from them inside anyway? If so, how would one fix such a thing?

Mine happens to be rusted right where the tube meets the corner of the roof. Almost didn't see it because of the accumulated silt. The tube itself is fine...just where it meets the metal floor of the roof, is rusted. Not sure how I'll fix it....probably some POR and some sort of thin sealant - maybe that rubbery stuff you dip tool handles into.

Good luck finding it!

-Larry

JimmyL · #11 04-22-2007, 10:04 AM

Quote:

Originally Posted by Larry Delor

Mine happens to be rusted right where the tube meets the corner of the roof. Almost didn't see it because of the accumulated silt. The tube itself is fine...just where it meets the metal floor of the roof, is rusted. Not sure how I'll fix it....probably some POR and some sort of thin sealant - maybe that rubbery stuff you dip tool handles into.

Good luck finding it!

-Larry

Larry, can you see it with just the sunroof open, standing over the top, or did you have to removed that lower front cover thing inside at the windshield?

captainmonk · #12 04-22-2007, 10:09 AM

is lower front cover thing the MB terminology???????

And why do we think 30 year old cars shouldnt have "known"problems 30 years after they were built

JHZR2 · #13 04-22-2007, 11:06 AM

yes, Im curious about the "lower front cover thing" too.

With the sunroof open, one can easily see the front sunroof drains. They are right at the front corners, and you can see a black hole going downward.

THey drain in front of the doors, but in the channel where the door jamb is, such that you can't really get to the little rubber plug without taking the door off. Thus why yu clean from the top down.

If I am missing something regarding analyzing these drains, Id love to know, as it might help me out quite a bit!

Thanks,

JMH

Bama1 · #14 04-22-2007, 11:50 AM

First of all, go ahead and take out your battery and inspect for rust-through at the firewall. (That should not be the problem unless the car has been really neglected or In this case the PO put in a tar and undercoat patch and glossed over it with spray paint like the rockers and the floor boards.) You may as well clean the battery tray and if needed, repaint or treat with POR 15 while you have the battery out. Be very careful to not bump the heater control valve on the firewall while you are removing or installing the battery. It is pretty close quarters and they will break very easily when smacked by a 40 lb battery.

Back to your main question concerning the most likely path of a water leak into the passenger compartment...Leaks could have more than one cause but my bet is on front and/or rear windshield seals needing replacement.

Check these threads...

http://www.peachparts.com/shopforu...d.php?t=164755

http://www.peachparts.com/shopforu...d.php?t=164697

http://www.peachparts.com/shopforu...ad.php?t=64843

Also Note Murrow's suggestion to chase the sunroof drains with weed-eater string to clear them out and not damage the finish. (That is if you have a sunroof)

Hope this helps
Motor on

Larry Delor · #15 04-22-2007, 11:41 PM

Quote:

Originally Posted by JimmyL

Larry, can you see it with just the sunroof open, standing over the top, or did you have to removed that lower front cover thing inside at the windshield?

Nothing needed to be removed. Just open the roof - you can either open the door and stand on the sill, or step on your seats (take your shoes off) and look at it that way.

PS: While you're standing on your seats, you can wave at people, as if you were in a parade.