Minor Gas Leak - any suggestions?

moulesy

Just bought a replacement 3.9kg propane calor gas tank. When I connected it up there was a distinct smell of gas and on checking I could hear that there was a leak. This appears to be a problem with the tank itself as when I connected up my spare (full)
 tank, there was no problem. Never had this happen before - anybody know a likely cause and a solution - I don't really want to have to pay for another replacement tank and waste the one I've got.