Driver's Side Leak - Please Help!
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E420
Driver's Side Leak - Please Help!
Hello all... I wonder if anyone can help me with an interior leak problem. I have MB rubber mats on the floorboards of my vehicle. Under the rubber mat on the driver's side footwell is a leak - lots of water. No water appears on top of the mat. My mechanic said he cleared the drainage lines and that should have fixed the problem, but the problem persists. Please don't tell me it's the condenser! I had the condenser replaced about 6 years ago to the tune of several thousand dollars! Perhaps the mechanic I took it to for the condenser replacement did not properly hook up the drainage lines? I would like to repair this problem, I just hope it's not the condenser again! Note: I do not smell that oily/gross smell that is present when the condenser is going out and the AC is working well... The carpet mats and the foam backing take a week to dry out - even in this terrible El Paso heat! One other note: last summer, I was gone for six weeks & I left the car parked outside and there were many rain storms while I was gone. Upon my return, the driver's footwell had gallons of water in it, this leads me to believe it is a drainage line problem (possibly from the outside under area of the windshield), but I do not know how to locate these drainage lines from the top... Any help and/or advice would be greatly appreciated. Thank You!
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I checked the front sunroof drains by pouring a quart of water into both the passenger and driver's side sunroof drains. The carpet with the foam backing is currently out of the car and I did not see any water leaking inside the driver's side footwell. The water ran out the drain tubes outside the vehicle just in front of the lower door area... The car is parked with the front end in a slightly downward angle. Are there drains in the rear of the sunroof as well? I can repeat this experiment for the rear drains if need be.
Any other ideas? Thanks!
Any other ideas? Thanks!
Last edited by dallas687; Aug 10, 2014 at 10:43 PM. Reason: added information
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ok... I figured out where the leak is coming from. I originally thought the outside under-windshield drains were the culprit and I was correct. They appear to be working, but some of the water leaks inside the car - particularly on the driver’s side and a bit on the passenger side. I think the water is running down the outside inner fender and then finding it’s way inside the car.
Any suggestions on how to address this problem? Thanks...
Any suggestions on how to address this problem? Thanks...
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In case anyone is interested, the problem turned out to be rotten foam evaporator drainage tubes located near the central drain under the windshield wiper. This was causing water to enter the driver's floorboard (and the passenger footwell to a lesser extent). Replaced with rubber hose and that fixed the problem.
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1990 W126 560SEL, 1995 W124 E420, 2000 W210 E320 wagon non 4 matic
I have been having same problem especially on passenger side in rain storms resulting in a fire from shorted out Alarm system under passenger floor mat. I have cleaned drains under windshield the Passenger side was clogged but that does not explain why inside car I will check the central drain as you suggested.
Do you have any pictures or diagrams?
Do you have any pictures or diagrams?
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rokacook. Unfortunately, I do not have any photos. I would definitely check the foam evaporator drainage lines. These foam lines deteriorate and cause interior leaks. If you are familiar with the process to change the cabin filters, this will help. You will need to dismantle the drainage channels as well as the central screen catchment area above the cabin filters - just under the central wiper mechanism. I believe you can access the foam evaporator lines once you do this. I replaced mine with rubber tubing. You may be able to search for "evaporator drainage line replacement" or something similar and find either a tutorial or at least a diagram and possibly some photos. It only took me 2 years to figure out the source of my leak! Good luck!
Last edited by dallas687; Mar 26, 2015 at 05:09 PM.
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1990 W126 560SEL, 1995 W124 E420, 2000 W210 E320 wagon non 4 matic
Whoever replaced windshield goofed
Seems that a plastic strip that goes at the base of windshield to which the rubber outer trim seal affixes was never replaced. So I am going to replace it later in the mean time I sealed the rubber with clear silicone and water proof black tape to keep water from getting into blower box. This solution seems to be working for now. I now am tracking down short from alarm-door lock system that causes wires to burn and fuses to blow, traced so far to brown ground wires inside console are fused to hot wires this leak almost caused my car to burn up. Fix interior leaks ASAP or you will end up with the same problem. 
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1990 W126 560SEL, 1995 W124 E420, 2000 W210 E320 wagon non 4 matic
As it turns out it was not windshield or sunroof drains etc at all. it was the rear tire well front panel had rust holes and the wheels were pumping water in like the Robert E. Lee on the Mississippi. No more water inside at all now. 
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1990 W126 560SEL, 1995 W124 E420, 2000 W210 E320 wagon non 4 matic
No only did you win the race to discover leak, but also the promptness to post replys. I was searching another forum on my W210 and realized I never gave update on my W124 water issue. now dealing with power steering hoses deterioration due to age. on the 420 will pull motor to gain access. I discovered after I raised motor to replace motor mounts, that the fragile PS hoses tore apart. only 1,500 made world wide I will keep her going as long as I can.
now dealing with power steering hoses deterioration due to age. on the 420 will pull motor to gain access. I discovered after I raised motor to replace motor mounts, that the fragile PS hoses tore apart. only 1,500 made world wide I will keep her going as long as I can.
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rokacook: My W124 ('94 E420) has 228K miles. I've yet to come across a part I cannot find. I truly believe you can easily keep these old warriors running almost indefinitely - it just take time and $.
You might consider Rein engine mounts. They are much cheaper than Genuine and they are the correct liquid-filled engine mounts. I was unable to find a definitive country of manufacture for Rein, but I believe they are made in Germany, based upon what I read. I replaced my engine mounts with Rein, they were one of the only engine mount manufaturers I could find that had the correct, liquid-filled engine mounts and they were highly praised on a Porsche forum.
If you don't already know, you should avoid URO/Meyle and Feibi/Bilstein parts like the plague - they are Chinese crap. You will be sorry if you use these parts. Victor-Reinz parts are suspect as well. Elring and Lemforder parts are good quality.
You might consider Rein engine mounts. They are much cheaper than Genuine and they are the correct liquid-filled engine mounts. I was unable to find a definitive country of manufacture for Rein, but I believe they are made in Germany, based upon what I read. I replaced my engine mounts with Rein, they were one of the only engine mount manufaturers I could find that had the correct, liquid-filled engine mounts and they were highly praised on a Porsche forum.
If you don't already know, you should avoid URO/Meyle and Feibi/Bilstein parts like the plague - they are Chinese crap. You will be sorry if you use these parts. Victor-Reinz parts are suspect as well. Elring and Lemforder parts are good quality.
