ML 320 W164 - Water in the Boot - Fixed?

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Jul 17, 2003
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278
Car
E500
Have been chasing a water leak under the tool carrier in the boot. Have dried it out 3 times and used talc to track the leak. Suspects are the Door seal and the rear light seals.

However after a soaking I found that water is leaking in the top of the third brake light and running inside the rear window trim and down into the boot floor.

As a double check I put the heat and fan on high and feeling at the top of the rear light there was air leaking through.

I have taped it up for now and ordered a replacement rear light. There was a few drips below the rear lights so have ordered light seals as well.

Hope this helps other MLs with water in the boot.
 
water

Topdown you can remove the rear cluster [light] and put some silicon grease on the rubber seal.It wont perish the seal as its good for rubber items. I use this on my airgun rubber seals,to preserve them . As when i removed my rear cluster i put this on my seal ,it works fine. At one time you could buy a product by the name of Seek and Seal by Comma i think thats the way its spelt. Realy good for window screens ,clear going on and it travels in to the crack of the rubber seal with the rain water .
 
Not fixed!:doh:

Replaced both light cluster seals and the High Level brake light - these were letting in water and the new cluster seals are a lot thicker. The high level brake light seal was perished.

Inspected again last week and there was 1/2" of clean water in the boot below the foam tool holder. Dried it all out and established that both left and right areas below the light clusters are dry as I had put talc over the area to track leaks. The R/H side is critical as that is where the rear Sam lives.

Sprayed water ( too simulate rain) from every angle and it was dry. (I have never pressure washed under the rear wheel arches as there are vents there.)

Checked again after a couple of days of rain, and the 1/2" of water is back - light cluster areas still dry as well as the high level brake unit.

Have left out 2 grommets for now so it drains.

Next plan is to strip out the rear seal and door housing and see if there is a blocked drain as a lot of water gets into door area at the top.Thought about adjusting the closing of the door but the gaps look good.

Would appreciate if anyone has any other ideas.

Spoke to the dealer and this can be a merry dance and very expensive to investigate.
 
Not fixed!:doh:

Replaced both light cluster seals and the High Level brake light - these were letting in water and the new cluster seals are a lot thicker. The high level brake light seal was perished.

Inspected again last week and there was 1/2" of clean water in the boot below the foam tool holder. Dried it all out and established that both left and right areas below the light clusters are dry as I had put talc over the area to track leaks. The R/H side is critical as that is where the rear Sam lives.

Sprayed water ( too simulate rain) from every angle and it was dry. (I have never pressure washed under the rear wheel arches as there are vents there.)

Checked again after a couple of days of rain, and the 1/2" of water is back - light cluster areas still dry as well as the high level brake unit.

Have left out 2 grommets for now so it drains.

Next plan is to strip out the rear seal and door housing and see if there is a blocked drain as a lot of water gets into door area at the top.Thought about adjusting the closing of the door but the gaps look good.

Would appreciate if anyone has any other ideas.

Spoke to the dealer and this can be a merry dance and very expensive to investigate.

Topdown did you ever get this fixed? I have exactly the same problem:( - spent 1/2 day yesterday trying to track it down doing all the stuff you mention
 
Not fixed and after making sure there is no water on the RH side where the SAM lives I have left the rubber bungs out and what water gets in leaves just as quick. If you get a cure I am sure a lot of people will be interested.
 
Same problem here with my 07 ML420. I don't have standing water in the boot but I have fried out two rear SAMs. The second time around the rear SAM was under a fitted plastic shield to protect the top of the SAM, but the SAM still had an ingress of water from the top.
Looking at the multi-plug seats it looks to me that water is making it's way into the top of the SAM by running/seeping down the wires that lead to the block connectors. The wires have a sticky wrap on them so they don't seem to absorb the water, they just channel it to the top of the SAM.
I still can't identify where the water is coming in from, but now being lighter in the pocket I'm going to attack the problem with Capt Tolley's Creeping Crack Cure, Butyl sealing tape and thin rubber sheeting to try and protect the SAM.

BB
 
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+1 for Captain Tolleys. As it is white when wet you can check inside for the place where it comes through, then reapply it outside (as directed) till it seals the leak. Also as it is very thin, you can see it running into some cracks, but flowing round others - also helpful in tracing leaks. Meths gets rid of the excess.

Excellent stuff if used correctly.
 
I think I've fixed my leak. It appears to have been coming from the side bolt hole where the offside rear light cluster fixes through the OSR panel. I taped over the hole on both sides with butyl tape and made a hole for the securing bolt to go through. Once I fitted the light back on I've not had the slightest bit of moisture come through.

As a belt n' braces fix I've also lifted up the rear SAM from its mounting bracket and stood it up on its end. I've then pulled a large plastic bag over it so that all the wire runs go down and then up into the bag so no water can track along them.

I also stopped using car washes that use pressure washers.

Hope this helps someone out with their water issues!

BB
 
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Please help! I have a leak, its a vito 2010 traveliner and there is water running down the inside panels below both rear windows and behind the plastic liner. The rear windows are also leaking a bit and will look at the seals but this other water seems to be coming from the metalwork behind the sliding door tracks - can it get in from them? its particularly bad just behind the speakers and is making the wadding wet. I can't see its related to the windows unless the rain is blowing it up and under the seals with the bodywork but this seems unlikely.
Does anyone have any ideas?
Thanks
Elly
 
Not fixed!:doh:

Replaced both light cluster seals and the High Level brake light - these were letting in water and the new cluster seals are a lot thicker. The high level brake light seal was perished.

Inspected again last week and there was 1/2" of clean water in the boot below the foam tool holder. Dried it all out and established that both left and right areas below the light clusters are dry as I had put talc over the area to track leaks. The R/H side is critical as that is where the rear Sam lives.

Sprayed water ( too simulate rain) from every angle and it was dry. (I have never pressure washed under the rear wheel arches as there are vents there.)

Checked again after a couple of days of rain, and the 1/2" of water is back - light cluster areas still dry as well as the high level brake unit.

Have left out 2 grommets for now so it drains.

Next plan is to strip out the rear seal and door housing and see if there is a blocked drain as a lot of water gets into door area at the top.Thought about adjusting the closing of the door but the gaps look good.

Would appreciate if anyone has any other ideas.

Spoke to the dealer and this can be a merry dance and very expensive to investigate.
 
Hi not sure how old this is but whould like to add to the sorry tale.
my w164 ml as been a disaster from water entering the car aprox two years ago the car failed in a big way out late one night .

l found a huge amount of water in the boot dryed this out at this stage rear sam was damp dryed sam out gaskets on rear lights tempory grease up traced water through to under drivers seat lots of water and corosion to sam unit ther , took passenger seat out absolute night mare to do, coriosion to gateway unit .
had car on ramp I drained a kid you not gallons of water from sills.
, the sam units in my experience do recover if you get into them spray pcb with wd 40 and brush the pcb board use a magnifeying glass you will be suprised how much corosion you wil get rid .
Now back on the case as water getting in from rear lights I have changed to thicker gaskets but water still getting in , Indee tells my the rear light them self need replacing as that's how water gets in ? I have loads of pics on this sorry tale any on further thoughts please let me know,
 
Never got to the leak bit it was never at the sides only the centre and with lots of paint on all edges I left bungs out so the water drained away. Mercedes must know but as usual keep it a secret. Car sold last year.
 
Hi not sure how old this is but whould like to add to the sorry tale.
my w164 ml as been a disaster from water entering the car aprox two years ago the car failed in a big way out late one night .

l found a huge amount of water in the boot dryed this out at this stage rear sam was damp dryed sam out gaskets on rear lights tempory grease up traced water through to under drivers seat lots of water and corosion to sam unit ther , took passenger seat out absolute night mare to do, coriosion to gateway unit .
had car on ramp I drained a kid you not gallons of water from sills.
, the sam units in my experience do recover if you get into them spray pcb with wd 40 and brush the pcb board use a magnifeying glass you will be suprised how much corosion you wil get rid .
Now back on the case as water getting in from rear lights I have changed to thicker gaskets but water still getting in , Indee tells my the rear light them self need replacing as that's how water gets in ? I have loads of pics on this sorry tale any on further thoughts please let me know,

I found the water was coming in from the back edge of the rear quarter light glass. The seals that cover the back of the glass had loosened, but regardless of that water can trickle behind the seals from the roof area. The seals easily peal away to reveal the back edge of the glass, I used automotive silicone glazing to seal them. Also used a small amount of captain Tolley's leaking crack to seal the top edge of the rear quarter light seal.

I found issue by loading the areas ( above Sam unit area and same on opposite side) with lots of micro fibre towels and plumber drip pad and using hose pipe squirting on roof. It soon becomes apparent how it's getting in.
 
Hi not sure how old this is but whould like to add to the sorry tale.
my w164 ml as been a disaster from water entering the car aprox two years ago the car failed in a big way out late one night .

l found a huge amount of water in the boot dryed this out at this stage rear sam was damp dryed sam out gaskets on rear lights tempory grease up traced water through to under drivers seat lots of water and corosion to sam unit ther , took passenger seat out absolute night mare to do, coriosion to gateway unit .
had car on ramp I drained a kid you not gallons of water from sills.
, the sam units in my experience do recover if you get into them spray pcb with wd 40 and brush the pcb board use a magnifeying glass you will be suprised how much corosion you wil get rid .
Now back on the case as water getting in from rear lights I have changed to thicker gaskets but water still getting in , Indee tells my the rear light them self need replacing as that's how water gets in ? I have loads of pics on this sorry tale any on further thoughts please let me know,
Quick question, same car same issue. Could you help me out with where the drains are for the sills?

Many thanks
 

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