W219 CLS55 boot/trunk leak?

Discussion in 'Interior' started by moodi, Dec 2, 2019.

  1. moodi

    moodi Hardcore MB Enthusiast

    Messages:
    540
    Joined:
    Nov 4, 2018
    Location:
    Bedfordshire
    Car:
    CLS55
    Hi all,

    When changing my battery recently I noticed a small amount of water (enough to form a little puddle) in the boot floor. Only the lowest carpet was wet, the one that makes contact with the bare metal/plastic of the floor. I think it has just developed as I did check for leaks when buying the car based on the previous owners advice. He had a leak which turned out to be the metal strip on the boot lid.

    The following have been changed in the cars history, all before my ownership:
    - Boot chrome strip + silicone sealed for good measure
    - Plastic tabs on either side of the boot changed for new w/new clips. Best way to describe this is when the boot is open, the pieces either side that touch the bodywork, one on each side together with all the little rubber push clips that come with it

    Did a 'hose test' with 5 mins of continuous hosing all around the rear 1/4s and boot. Nothing, dry as a whistle inside with no obvious entry points for water showing. Nothing I could see that would indicate the rear light seals are leaking.

    Any thoughts? Could it be condensation and if so how/where should this be draining?
     
  2. Larkone

    Larkone Hardcore MB Enthusiast

    Messages:
    607
    Joined:
    Jun 13, 2016
    Location:
    Essex
    Car:
    2008 CLS 320 CDI facelift
    The rubber push clips on the two plastic strips are fragile. They can be resealed with silicone. Also there are supposed to be channels under the strips to drain water off the rear window area, these fill up with foliage and rot down to a nice black mush that holds water/blocks drainage. This could be getting around the edge of the rubber push clips.

    Check that the seals on the lights haven't compressed and started to leak. You will have to remove the lights to be sure as you can then see if water has got past them. These can be sealed either with silicone sealant or silicone grease if you are worried about getting them out again. Easy to unbolt - 5 bolts, once you have removed the boot trims.

    Are there any leaks around the plastic wheel tray and the bodywork, missing plugs, splits etc. Try the water test from underneath.
     
  3. OP
    OP
    moodi

    moodi Hardcore MB Enthusiast

    Messages:
    540
    Joined:
    Nov 4, 2018
    Location:
    Bedfordshire
    Car:
    CLS55
    Thanks for the reply. 90+% confident it isn't coming from the topside - there is not a single sign of any water having parked the car up for 4 days with frequent showers courtesy of mother nature. Checked each day multiple times.

    Now thinking it is coming from underneath when driving, something missing perhaps or a bad seal. Next stop = plumbers smoke pellets and I'll be smoking the ol' girl. Hopefully that will show it.
     
  4. mattk1

    mattk1 Hardcore MB Enthusiast

    Messages:
    448
    Joined:
    Sep 1, 2011
    Location:
    Guildford
    Car:
    SL63, C350 CDI & Ducati 1299 Panigale
    Had something similar on my old CL, turned out to be a rear light gasket. Just a thought.

    Good luck, Matt :thumb:
     
    whitenemesis likes this.
  5. OP
    OP
    moodi

    moodi Hardcore MB Enthusiast

    Messages:
    540
    Joined:
    Nov 4, 2018
    Location:
    Bedfordshire
    Car:
    CLS55
    Did you have water only collecting on the boot tray?

    So bit of an update - used an under chassis lance to give the bottom a good soaking under pressure and no leaks. Smoke bombed the boot and found the slightest of weaps (whole boot full of smoke and only just misting) from the rear right light gasket. Could not get the leak to replicate with 5+ minutes of simulated rain on the rear light. Additionally strange as the water actually collects on the left side of the boot tray, but will be sealing it anyway just in case it is the culprit.

    Not convinced I have found the solution but will persevere.
     
  6. OP
    OP
    moodi

    moodi Hardcore MB Enthusiast

    Messages:
    540
    Joined:
    Nov 4, 2018
    Location:
    Bedfordshire
    Car:
    CLS55
    A more intense smoke test looks like it might be in this area. Although the last owner did replace the strips both sides and also the rubber push clips. He also siliconed around the clips before insertion.
     
  7. OP
    OP
    moodi

    moodi Hardcore MB Enthusiast

    Messages:
    540
    Joined:
    Nov 4, 2018
    Location:
    Bedfordshire
    Car:
    CLS55
    The strange thing is, having stripped the full trim boot (to bare metal) I can't find anything that looks like water ingress. No evidence of how the water is running or dripping to where it is.
     
  8. Larkone

    Larkone Hardcore MB Enthusiast

    Messages:
    607
    Joined:
    Jun 13, 2016
    Location:
    Essex
    Car:
    2008 CLS 320 CDI facelift
    OK - has something leaked from your shopping then or could it be condensation forming on the inside of the spare wheel tray.
     
  9. OP
    OP
    moodi

    moodi Hardcore MB Enthusiast

    Messages:
    540
    Joined:
    Nov 4, 2018
    Location:
    Bedfordshire
    Car:
    CLS55
    No and unlikely. The boot is currently stripped of all carpets and foam. The water only collects on the 'spare wheel tray' (plastic in my case and no spare wheel). It is extremely strange, like someone is opening the boot, pouring in some water and then closing the boot. No evidence for how it is getting in, strangely.
     
  10. OP
    OP
    moodi

    moodi Hardcore MB Enthusiast

    Messages:
    540
    Joined:
    Nov 4, 2018
    Location:
    Bedfordshire
    Car:
    CLS55
    Here is the exact situation I am dealing with, the water tends to leak in the following positions:
    1. The most common place. If there is water anywhere else there is always water here. It can pool to a small puddle.
    2. Water is here when the boot is opened, sometimes but not always, quantity can vary from a small drop to the amount seen in this pic
    3. As 2.
    The water can appear in other areas of the battery tray but due to 1. I am confident it is from driving after there is already water in 1 (and it swooshing around). Come to think of it, I have never seen water pool anywhere else when the car has been parked.

    Water leak is evident both when it has been raining (overnight) or after a long drive in rainy weather.

    Nothing points to water dripping or running in the boot and I cannot replicate the leak with a hose pipe or jet wash neither from above or underneath the chassis.

    For now I am keeping the boot stripped until I can figure it out.

    [​IMG]
     
  11. Major774

    Major774 Hardcore MB Enthusiast

    Messages:
    1,868
    Joined:
    Sep 6, 2012
    Car:
    W211 E55 AMG
    I have a leak in the same places as you do (W211 here).

    I am scratching my head as well, I have stripped the boot interior (trim) like you.

    I have a feeling it is coming from the boot lid. In hot weather my number plate surround (the large plastic cover on the boot lid) pops out on the top side. I have to push the top side back in on occasions. I am waiting for the summer to strip the boot lid and confirm my suspicion.
     
    moodi likes this.
  12. andy27168

    andy27168 Hardcore MB Enthusiast

    Messages:
    4,395
    Joined:
    Nov 27, 2004
    Location:
    Southampton
    Car:
    1997 C230K, 1999 C43/55 AMG
    I had a similar issue with my CLS55 (leaking in the same/similar places but on the other side of the boot) for the life of me as you I couldn't suss out where it was coming from, on the other side of my car in the boot I found an empty threaded hole (from the factory) which I found a bolt and washer and screwed it in. At the same time I replaced the trim pieces in the boot shut as others have suggested, cleaned and polished the underside of the boot lid, cleaned and lubricated the rubber boot seal which seemed to cure it though I didn't feel I had really found the source.
     
  13. OP
    OP
    moodi

    moodi Hardcore MB Enthusiast

    Messages:
    540
    Joined:
    Nov 4, 2018
    Location:
    Bedfordshire
    Car:
    CLS55
    I can't replicate my leak with the hose nor the pressure washer, so relying on every nights downpour to help me find the source. I am not running a number plate surround but will check behind the plate (holes).
     
  14. OP
    OP
    moodi

    moodi Hardcore MB Enthusiast

    Messages:
    540
    Joined:
    Nov 4, 2018
    Location:
    Bedfordshire
    Car:
    CLS55
    Got a pic of where this washer/bolt went? I haven't seen any empty holes yet. What did you use to lubricate the rubber seal? mine seems fresh, supple and clean.
     
  15. andy27168

    andy27168 Hardcore MB Enthusiast

    Messages:
    4,395
    Joined:
    Nov 27, 2004
    Location:
    Southampton
    Car:
    1997 C230K, 1999 C43/55 AMG
    Hi, to be honest my seal seemed perfect as well, but as I had some seal cleaner/lubricant for my Audi Cabriolet I used it, I used this one
    Nextzett Gummi Pflege, Rubber Care Stick, 100ml. 5412763148069 | eBay
    Sonax also do one which is cheaper, I like Sonax products so would probably buy that one when my current one runs out.
    I think cleaning the underside of the boot lid probably did the most improvement as it was dirty this I did with a APC and then gave it wipe down with Sonax BSD.
    I haven't got a pic of the threaded hole, and the car is at the body shop having the front bumper repaired/painted and a splitter fitted.
    Its on the driver's side of the boot from memory 3-4 inches up from the bottom and is either 8-10mm thread.
     
  16. Gbrowncls55

    Gbrowncls55 Hardcore MB Enthusiast

    Messages:
    891
    Joined:
    Sep 11, 2016
    Location:
    Surrey
    Car:
    CLS55 AMG 06, SL350 06, 996 cab, all current. Gone : E500 W211, 2x M5s and far,far too many 911s
    Mmm. Number plate mounting holes? Numberplate light lenses/rubbers both crack and perish. As you cant replicate it with a hose it obviously is very slow and takes time for it to accumulate. Has it ever had a rear end accident?
     
  17. OP
    OP
    moodi

    moodi Hardcore MB Enthusiast

    Messages:
    540
    Joined:
    Nov 4, 2018
    Location:
    Bedfordshire
    Car:
    CLS55
    No accidents to the best of my knowledge. Everything seems straight and clean. I have resorted to taping up various bits of the boot and hoping to narrow it down that way.

    I have new number plate lights and seals and will also be putting on a new chrome strip (although taping that up made zero difference, but going for a new one whilst the chrome is getting wrapped anyway).
     
    Last edited: Dec 22, 2019
  18. OP
    OP
    moodi

    moodi Hardcore MB Enthusiast

    Messages:
    540
    Joined:
    Nov 4, 2018
    Location:
    Bedfordshire
    Car:
    CLS55
    I have some, will try this.
     
  19. OP
    OP
    moodi

    moodi Hardcore MB Enthusiast

    Messages:
    540
    Joined:
    Nov 4, 2018
    Location:
    Bedfordshire
    Car:
    CLS55
    Can anyone confirm if there are any water drainages under the plastic strips on either side of the boot?

    And/or where the rear window drainages are.
     
  20. Larkone

    Larkone Hardcore MB Enthusiast

    Messages:
    607
    Joined:
    Jun 13, 2016
    Location:
    Essex
    Car:
    2008 CLS 320 CDI facelift
    No water drainage holes under the strips. The rubber grommets hold the strip away from the bodywork to allow water to flow and drain under the strip - and accumulate old leaves etc. as you will find a nice morass of rotted muck. The rubber grommets are what contributed to a leak on mine but I resealed them with silicone
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.