you may need to change the tap gear very easy to do
1: You will need
Step 2: Preparation
First things first - turn the water supply off, or you'll end up looking like a drowned rat. This can usually be done by turning the valve under the sink. If you can't find a valve you'll have to turn the water off for the whole building. Remember the old mantra 'lefty loosey, righty tighty', even the experts still use this one. When you have done this, turn the tap on to drain out the remaining water in the system.
Step 3: Remove the headgear
There are loads of different types of stem tap, but they work in the same way in that there'll be a decorative cap covering the gubbins. Use a flat head screwdriver to prise that off then undo the screw underneath. Next, lift off the headgear with your fingers. Don't use a wrench or spanner as you'll damage it. If your tap doesn't have a cap, you should find a small screw on the side. Unscrew this to lift off the headgear.
Step 4: The packing nut
Use the adjustable spanner to release the hexagonal packing nut. It can be pretty stiff, so grab the spout of the tap with your other hand for leverage. Once the nut is loose lift out the entire tap stem.
Step 5: Reassemble
Put the tap back together and don't forget to tighten everything up well. Then turn the water back on a check your handy work. Not a drip in sight. Another job well done.
done it many times