S-Class (W221) 2007-2013: S 320 CDI, S 350, S 450, S 500, S 550, S 420 CDI, S 600

Washer Fluid Container

Old Apr 19, 2019 | 10:54 PM
  #26  
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Post Reassembling the Windshield Washer Fluid Reservoir

Originally Posted by Pitek
Hi everyone,

I am almost finished with my promised write-up on reassembling the Windshield Washer Fluid Reservoir. I will post it very soon.

Thank you,
Pitek
Hi everyone,

This is my write-up on reassembling the Windshield Washer Fluid Reservoir after replacing the leaking seal/washer under the M5/1 Windshield Washer Fluid Pump and replacing the broken off connector between the M5/2 Headlamp Washer Fluid Pump and the Headlamp Washer Fluid Line.



I disconnected, removed and cleaned up inside and outside of the Windshield Washer Fluid Reservoir. You can clearly see where the Washer Fluid Level Sensor, and both pumps are located.

I installed brand new washer/seal (smaller on the left) and grommet (bigger on the right). The washer/seal was leaking badly especially when the ambient temperature occasionally drastically dropped down over the winter time.

I had to replace the connector between the Headlamp washer fluid pump and the Windshield washer fluid line. I broke it off despite friendly reminders and warnings from some members.

First, I firmly inserted one end of the connector into the Headlamp Washer Fluid line.

I lined up all of the components to be reinserted and reconnected on the side of the Windshield Washer Fluid Reservoir.

Close-up of the Headlamp Washer Liquid Pump and the thick rubber grommet it goes into.

This is the final and most important step in reconnecting the Headlamp Washer Fluid pump and the Headlamp Washer Fluid line. The room is very limited down there. You have to snap the connector on the pump's spout. Do not remove the clip off the Connector while installing it. The manufacturer pre-lubricated (white grease), the inside of the connector on the "snap-on" end.

I gently and slowly snapped on the connector after squeezing my hand in there. I had to use two straightened out fingers to accomplish it.

The Windshield Washer Fluid Reservoir sits on two pins (part of the reservoir), that go into two rubber grommets underneath.

This is an interesting photo. I took it looking down through the top round opening in the Reservoir. Familiarize yourself with surroundings inside. Find the round pocket at the very bottom and the center of the Reservoir. You will have to precisely slide in there the foot of the Heat exchanger.

Close-up of the Washer Fluid Heater foot.

It is extremely important that you do not use any force! Gently and slowly slide the Heat Exchanger Coil under the bulge (see the red outlined arrow). The moment the Heater's foot finds its final spot it will drop enough to slide it under the bulge.

You will need a 10 mm socket to screw the 10 mm nut holding down the entire Windshield Washer Fluid Reservoir.

First, clip back in the coolant lines (black arrows). Then, slide back the purging valve (soft rubber) on its metal bracket. Finally, tighten the 10 mm nut.

Reconnect the engine air intake duct.

Reconnected.

Reinstall the front engine cover.

The warning message still reads "Check Washer Fluid". Fill the Windshield Washer Reservoir. Inspect and adjust to correct level. Turn the engine on and try out if all the sprinklers (windshield and headlamps) work the way they are supposed to. There might be a slight delay (1-2 seconds) shooting the washer fluid out because there could be some air trapped in the lines. Check if nothing is leaking around the Windshield Washer Fluid Reservoir and right underneath it and under the car.

No messages. No leaking. All works. Job well done!

I hope it will help someone with the DIY project, saving money and bringing satisfaction from completing the task on your own and your leisure.

Thank you and Have a Happy Easter!

Pitek
Reply
Old Apr 19, 2019 | 11:19 PM
  #27  
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Nice work! Thanks for taking the time to document it and provide excellent photos!
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Old Apr 28, 2019 | 11:07 AM
  #28  
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Guys quick question, is the black clip part of the elbow or you had to buy them separately?

Originally Posted by konigstiger
Take a chance on 2088690024, not specific to w221 but seems to match.


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Old Apr 28, 2019 | 11:31 AM
  #29  
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Originally Posted by COUPCONNOISSEUR
id like to add on to this, i didnt do my research and put the rainx washer fluid in my reservoir and used as normal..after bringing it to the dealer for something unrelated i was told i put the wrong fluid in and damaged the sensor..is this accurate?
Yes, there is a bulletin advising not to use Rainx because it fouls the quantity sensor.
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Old Apr 28, 2019 | 11:31 AM
  #30  
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Thank you for this write-up!!! Previous posts have said the factory washer shrinks and that's what causes most of these links. Someone mentioned an aftermarket rubber washer that works better, is thicker and DOESN'T leak. Is that what you used???

Mine has been replaced twice by the dealer and I think it was the small factory washer that makes this happen again and again.
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Old Apr 28, 2019 | 02:24 PM
  #31  
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Originally Posted by bshad74
Guys quick question, is the black clip part of the elbow or you had to buy them separately?
The black plastic clip always comes with the connector. It does not matter what the colour of the connector is (white or black).
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Old Apr 28, 2019 | 09:03 PM
  #32  
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Wink Leaking washer

Originally Posted by Jason B
Thank you for this write-up!!! Previous posts have said the factory washer shrinks and that's what causes most of these links. Someone mentioned an aftermarket rubber washer that works better, is thicker and DOESN'T leak. Is that what you used???

Mine has been replaced twice by the dealer and I think it was the small factory washer that makes this happen again and again.
Hi Jason,

My washer did not shrink. Just the opposite. It got worn out and loose. Look at the close-up photos I posted:
https://mbworld.org/forums/s-class-w...ml#post7717720

I bought a brand new washer at the local stealership. I did not bother with a cheap aftermarket replacement (e.g. Made in China). I did not want to wait 5-6 weeks for it. I wanted to fix it a.s.a.p. And I did.

I hope that helps.

Pitek
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Old Nov 14, 2019 | 05:30 PM
  #33  
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Old Feb 3, 2020 | 06:03 PM
  #34  
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OK, so i can no longer STAND the blue stains on my driveway, and having to refill my washer fluid every 2 days!! i would love to tackle this project this weekend. i want to have everything on hand to replace on the first try(aside from the reservoir itself and the pumps as im pretty sure they are fine)..the part number for that elbow i have as they are in this thread, but does anyone have the numbers for whatever grommets and anything else i need to be changing?..im buying that elbow as well because im positive ill be breaking that lol

thank you as always friends.
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Old Feb 4, 2020 | 06:46 PM
  #35  
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HA, I thought I was the only one, but I filled the thing up with a gallon of Rain-X, and a week or two later it's telling me it's low. I have no intention of taking anything apart! No driveway stains, wonder where it went. I'll just wait till the weather warms up and try again. Hopefully warm weather will be all it wants. If it still leaks I'll do something about it. Lucky for me the Rain-X product leaked out. Next I'll get the other brand. I still rub Rain-X all over the glass (the water repellent stuff) so that's all the rain repellent I need. Hope that in the spring it won't leak. My W140 had a bag hidden in the fender that holds the washer fluid, and I screwed up the lines when I replaced that car's radiator, which I didn't even need to replace: I was just overfilling it. Then when I sold the W140 the buyer complained up a storm that the washer fluid system didn't work!!!

Last edited by tonylinc; Feb 4, 2020 at 06:50 PM.
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Old Feb 5, 2020 | 05:18 PM
  #36  
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anyone? part numbers? please?
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Old Feb 5, 2020 | 09:53 PM
  #37  
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https://nemigaparts.com/cat_spares/e...86/65v/86/030/
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Old Feb 8, 2020 | 09:56 PM
  #38  
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replaced all the grommets and seals on the tank reassembled and refilled with washer fluid and its still leaking..what else could be wrong?
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Old Feb 9, 2020 | 06:20 AM
  #39  
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Fill it and leave overnight or longer

Then look at the fluid level and see what is installed at that level. That’s the item that is leaking

it will only leak down to the level of the defective/ leaky part and then stop


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Old Feb 9, 2020 | 04:27 PM
  #40  
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Originally Posted by bha
Fill it and leave overnight or longer

Then look at the fluid level and see what is installed at that level. That’s the item that is leaking

it will only leak down to the level of the defective/ leaky part and then stop
thanks bha, after filling it and narrowing it down. my problem appears to be the windshield washer pump and not the grommet(the grommet is brand new) has anyone ever had the pump itself leak?
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Old Oct 18, 2021 | 05:58 PM
  #41  
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Great photos

Originally Posted by Pitek
Hi everyone,

This is my write-up on reassembling the Windshield Washer Fluid Reservoir after replacing the leaking seal/washer under the M5/1 Windshield Washer Fluid Pump and replacing the broken off connector between the M5/2 Headlamp Washer Fluid Pump and the Headlamp Washer Fluid Line.



I disconnected, removed and cleaned up inside and outside of the Windshield Washer Fluid Reservoir. You can clearly see where the Washer Fluid Level Sensor, and both pumps are located.

I installed brand new washer/seal (smaller on the left) and grommet (bigger on the right). The washer/seal was leaking badly especially when the ambient temperature occasionally drastically dropped down over the winter time.

I had to replace the connector between the Headlamp washer fluid pump and the Windshield washer fluid line. I broke it off despite friendly reminders and warnings from some members.

First, I firmly inserted one end of the connector into the Headlamp Washer Fluid line.

I lined up all of the components to be reinserted and reconnected on the side of the Windshield Washer Fluid Reservoir.

Close-up of the Headlamp Washer Liquid Pump and the thick rubber grommet it goes into.

This is the final and most important step in reconnecting the Headlamp Washer Fluid pump and the Headlamp Washer Fluid line. The room is very limited down there. You have to snap the connector on the pump's spout. Do not remove the clip off the Connector while installing it. The manufacturer pre-lubricated (white grease), the inside of the connector on the "snap-on" end.

I gently and slowly snapped on the connector after squeezing my hand in there. I had to use two straightened out fingers to accomplish it.

The Windshield Washer Fluid Reservoir sits on two pins (part of the reservoir), that go into two rubber grommets underneath.

This is an interesting photo. I took it looking down through the top round opening in the Reservoir. Familiarize yourself with surroundings inside. Find the round pocket at the very bottom and the center of the Reservoir. You will have to precisely slide in there the foot of the Heat exchanger.

Close-up of the Washer Fluid Heater foot.

It is extremely important that you do not use any force! Gently and slowly slide the Heat Exchanger Coil under the bulge (see the red outlined arrow). The moment the Heater's foot finds its final spot it will drop enough to slide it under the bulge.

You will need a 10 mm socket to screw the 10 mm nut holding down the entire Windshield Washer Fluid Reservoir.

First, clip back in the coolant lines (black arrows). Then, slide back the purging valve (soft rubber) on its metal bracket. Finally, tighten the 10 mm nut.

Reconnect the engine air intake duct.

Reconnected.

Reinstall the front engine cover.

The warning message still reads "Check Washer Fluid". Fill the Windshield Washer Reservoir. Inspect and adjust to correct level. Turn the engine on and try out if all the sprinklers (windshield and headlamps) work the way they are supposed to. There might be a slight delay (1-2 seconds) shooting the washer fluid out because there could be some air trapped in the lines. Check if nothing is leaking around the Windshield Washer Fluid Reservoir and right underneath it and under the car.

No messages. No leaking. All works. Job well done!

I hope it will help someone with the DIY project, saving money and bringing satisfaction from completing the task on your own and your leisure.

Thank you and Have a Happy Easter!

Pitek
thanks
Reply

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