C5 Mk1 Roof Gutter Leak And Fix.

[aspire_helen]

Owners of older cars may wish to check the mastic along the roof gutters (under the plastic cover strips) and hatch door side gutters for hairline cracks resulting in water leaks, possibly evident by a damp patch on the headliner.

 

I had such an intermittent damp patch to the rear corner which i put down to the hatch's annoying habit of pouring water into the boot when opened. However, the absorption of the headliner was disguising a leak eminating from between the spot welded panel joins below the hatch. This had resulted in a black mouldy patch inside the headliner but not evident from the car interior.

 

On close examination, on removal of the plastic strips covering the roof gutters, there were hairline cracks in the external mastic. On the damp side the crack also ran 2 inches into the gutter down the side of the hatch door.

 

I fixed the leak by running a bead of "windscreen and glass sealer" along both gutter seams and the cracked mastic. The "free flowing silicone" is less viscous than normal silicone sealant and flows into minute cracks before setting. VersaChem Part no 75009, 42g tube from Ebay.

[paul.h]

I got fed up of the rain collected on the hatch getting in the car when it was opened on our first C5 but if you change to an estate this problem goes. I tried using sealant at the bottom of the glass/trim and in the holes at the door edges of this plastic trim but these did not help.