All glazing components on the MGC, windscreens, drop glass, quarter lights, rear screens (GT), and their associated seals, channels, fixings, and hardware, are the same as those fitted to the contemporary MGB (1967 to 1969 specification). The windscreen is a laminated safety glass unit sealed to the body aperture by a rubber seal with chrome finisher strips covering the joint. Drop glass panels in each door slide up and down in felt-lined channels operated by a winder mechanism, with the glass itself available in both clear and tinted options. Quarter lights pivot open for cabin ventilation.
The GT rear screen is a fixed unit bonded or sealed into the tailgate.
Seal Condition and Water Ingress
The most common glazing-related problem on the MGC is water ingress caused by deteriorated rubber seals, the windscreen seal, rear screen seal, and quarter light seals all harden and shrink with age, opening gaps that allow rainwater to enter the cabin, staining headlining, soaking carpets, and promoting corrosion in the scuttle and sill areas. Replacing all glazing seals during a restoration or when water ingress is noticed is strongly recommended, the cost of the seals is negligible compared to the bodywork repairs needed to address the corrosion that persistent water ingress causes.
Drop Glass and Quarter Lights
Drop glass channels and felt runners should be replaced whenever the glass is removed, as worn channels cause the glass to rattle in its frame, scratch against bare metal, and drop under its own weight. Quarter light pivot mechanisms stiffen with age and can be freed with careful lubrication, or replaced if the pivot is worn beyond adjustment. Rubber seals around the quarter light frame prevent water from entering the door cavity and should be renewed if they have lost their flexibility.