Make sure you replace the copper crush washers when you remove the banjo bolt. You CAN reuse the old ones, but it'll only cost ya about 2 bucks if you go to your local Pirtek or Enzed and get a replacement set....bring the old washers with ya to match the size though!

If you install the banjo bolt with no washers (some people dont realise there are washers there cos they lose them in the removal process), you'll soon know about it