SL/R230: Windshield Washer Reservoir Leak at Neck
Thread Starter
Junior Member
Joined: Jul 2021
Posts: 25
Likes: 13
From: Clearwater, Florida
2004 SL500
Windshield Washer Reservoir Leak at Neck
The white plastic windshield washer reservoir is filled through a black plastic neck which leaks where they meet. I read this is a common problem, so there must be some who have a clever way to fix it. Without going through the trouble of removing the wheel and fender inner panel, I'm asking if anyone knows if this joint is accessible so that it can be sealed. Or do we just accept it and not fill to the top? Unfortunately you cannot see the joint when filling, so it needs to be sealed.
Thanks for information.
Thanks for information.
Super Member
Joined: Aug 2017
Posts: 520
Likes: 203
From: Scottsdale AZ
2015 SL550 & 2012 S550 4matic
I chose to accept it and don’t fill the reservoir beyond 80%.
A few weeks ago I was testing the wipers and windshield sprayers, and the headlight washers. What a mistake. The headlamp washers began to leak, draining the reservoir turning the light on the IC.
The fix is to replace. To replace you need to drop the bumper. Not a bad DIY, but a PITA, for a silly and useless spray device.
A few weeks ago I was testing the wipers and windshield sprayers, and the headlight washers. What a mistake. The headlamp washers began to leak, draining the reservoir turning the light on the IC.
The fix is to replace. To replace you need to drop the bumper. Not a bad DIY, but a PITA, for a silly and useless spray device.
Senior Member
Joined: Nov 2021
Posts: 469
Likes: 119
From: North West England
SL500
I need to replace one washer on my car, as it is cracked at the nozzle, and sprays water all over the car next to mine when operated!
Reading WIZ, you do not need to remove the bumper, just loosen one side, which gives enough gap to get at the hose and mounting.
Still a PITA though!
Reading WIZ, you do not need to remove the bumper, just loosen one side, which gives enough gap to get at the hose and mounting.
Still a PITA though!
Junior Member
Joined: Feb 2019
Posts: 33
Likes: 8
From: Tampa, FL
2007 SL550
As MBCO says, if the leak is where the upper neck connects to the reservoir, then you can still fill to at least 80% without issue and everything should work as normal, so consider just leaving it. I realized this was my issue by removing the inner wheel panel to inspect - I originally thought the leak was lower down somewhere. This gave me direct access to this pipe and since I was there I took the opportunity to seal around the connection with caulking. Easy DIY.
Thread Starter
Junior Member
Joined: Jul 2021
Posts: 25
Likes: 13
From: Clearwater, Florida
2004 SL500
Thanks, Sozo. That's what I needed to know. Some 3M 5200 ought to do the trick. The MB dealer had a mechanic look at it and quoted $400 to fix it. From what they said, it was unreachable and had to be removed to do it. Sometimes I wonder about those folks....
Thanks again.
Thanks again.
Last edited by rrueckwald; Nov 24, 2021 at 07:59 AM.
