If running it with the cap of doesn't get rid of it (it should) or squeezing top hose, try and borrow a radiator pressure tester (a pump with a fitting which goes on to the rad cap - probs need to use an adaptor on a LR, and use it on the expansion tank, it pressures it up to check for leaks - but removes air locks etc aswell. Just a thought, may not work on a LR rad?
