ML Tailgate / Rear quarter window seal - Leak issue

[Crustyclam]

Hi,

So recently I discovered to my dismay I have a water leaks ingressing above the rear Sam unit, and the exact opposite side.

I replaced the light cluster seals both sides, but the issue still persists both sides.

After further investigation with the help of a hose pipe, squirting water on the roof I managed to pinpoint the leaking areas from within the boot area. Water is running down roof rail gulley area and underneath the seal.
(Seal highlight into photo with 1 red arrow)

It's appears that the water is coming into the bodywork under the very rear of the quarter window area.

Now the rubber seal that covers the back of the quarter window isn't particularly snug against the glass.
The rubber seal peals away to reveal the full back edge of the glass which fits against the bodywork, water is actually disappears between this join. I suspect it's this water that's making its way into the back of vehicle.

I have run a slight line of silicone down this area, leaving the bottom 3-4mm free, allowing any water to egress. (Noted this is where a lot left after disappearing with hose pipe test)

So going to see if the silicone helps, but I am going to replace the seals as a matter of course, as these will still limit the water getting behind.

I rang my local MB main dealer and they struggled to identify what needed replacing.

Rang main dealer in Newcastle who were extremely helpful, and with an exchange of photos I think the part was identified. (However the part diagram was lacking a little and doesn't show in great detail).

Myself and the parts chap are fairly sure it's the one highlighted in another attached photo (parts diagram). We think the rubber seal may be attached to the full plastic trim.

I have checked my car and again it kinda looks like it will be, just not 100% sure.

Anyone know? If the full part is needed do I need to remove the bumper, looks like a hard to reach securing plug. Photo attached with dog hair....yes it's a dog hair

This is the cheapest step to replace seal, however if that fails (and given the water flow path) I think I will need the quarter lights replacing or re-sealing, any advice on that? Asked my local main dealer for a price, but not returned my calls.( rung multiple times).

Thanks

Lee

 

[Crustyclam]

This photo may help also to compare against the parts diagram.

 

[Crustyclam]

I shouldn't speak to soon, but was lashing it down this morning on my journey to Manchester and not a drop of water entered.

I have microfibres towels placed either side to catch any drips. Bone dry for the first time after such heavy rain.