Rain water leak into boot / trunk (hatchback) - with fixes

[Mazda6JW]

I think I have sorted the water leaks!

I removed the aperture seal and cleaned off the white sealant and I went round the whole pressed together edge with the flowable silicone sealant, as well as the left hand and right hand seams where roof panel meets rear panel, then fitted a replacement (used, but in better condition) aperture seal after treating the seal with copious amounts of Gummi Pfledge (rubber conditioner).

I removed the rear bumper and rear outer light clusters, and noticed that the locating lugs (for the lights) and the plastic bumper mounting grommets were loose (rubber gaskets had shrunk), so I removed them all and used silicone sealant (paint safe type) to seal them to the body, I also put some sealant under the clip that holds the number plate illumination wiring to the body, and around the rear vent flap unit. (See attached photo's to see locations of fixes).

New photo · Wednesday, Nov 19 - Left side

New photo · Wednesday, Nov 19 - Right side

New photo · Wednesday, Nov 19 - Right hand seam (with pinhole circled)

I also ordered a complete set of light gaskets to prevent any leakage through the light areas (around £25 including delivery from Ali Express) https://www.aliexpress.com/item/1005005 ... 1802mucwOK

I will confirm if the fixes described above are successful, I'm fairly confident the sealing will work because I found a dirt trail from the left hand upper bumper screw grommet, which runs down into the lower left recess that the water was pooling in.

 

[Mazda6JW]

Really disappointing - I've just checked the rear of the car and found water in the left rear recess (behind the wheel arch). Leak seems to be dripping into the front end of the recess, as the rear end is dry (so at least the bumper fixing waterproofing worked!) I'm a bit puzzled about where the leak can be coming from, as I thought I had sealed every possible source. A mechanic friend suggested drying it out with kitchen roll and then spraying the whole panel with cheap anti-perspirant (the type that leaves white marks) so that water track marks can be seen - I've done this and it has crystalised in some places where water is on it, but it isn't clear where the source is - my suspiscion is that it is coming from the left rear wheel arch, i.e. water being sprayed up from the tyre in the wet, as it doesn't get wet inside when the car is stationary and it is raining.

Any suggestions for possible leak areas, that I haven't already mentioned in the previous post, would be much appreciated.

New photo · Monday, Nov 24 - highlighted area is where the water is collecting (it is NOT wet to the left of the white sealant directly below the vent flaps).