Hi, every time it rains, especially heavy which in the UK is most days, my boot fills with water. It must be coming in past the seals, can't see how. There is a gap all around the boot is this normal, I thought it is as the seals will stop the ingress of water. Mine is a 2003 Cooper s model. Is this a common fault and what is the fix, my boot carpet and battery are soaking. Also would this affect the function of the battery. Due to an arm injury I can't drive my mini for 8 weeks, after the first 2 weeks the battery is totally flat is this connected with the water issue. Another question I have an optimate trickle charger so thought about buying a connector that fits into the cigarrette lighter will this charge the battery if the ignition is off. I don't have the battery terminal connector as this was stolen along with my motorbike last week, another story.
Thanks
Nick

MINI say, in the handbook, it is not advisable to charge the battery via the cigarette lighter socket.
If you are getting water in the boot, and the rubber seal seems ok and not torn or flattened, there should not be a gap all around the rubber seal where it contacts the body aperture when the hatch is shut if thats what you mean? Then other places it can get in is via the rear light seals or the high level brake light unit, that seems to be the cause most often.
Check rear hatch bottom drain hole is not blocked also.

I have the sme problem the carpet is dry but the sponge underneath it it dripping wet. The break light seems okay and the seal looks good too. Still trying tomfind were the water is coming from.

Had the same problem with water leaking into the boot of my 2003 mini cooper. It was the rear screen wash water running down onto the boot chrome finisher housing number plate lights & boot release.
The cure was replacing the seal behind said item Part no.M51.24.7.114.521 042605/Gasket £6.29 + vat.