cistern only filling up half way.I push the ball down and hold it to take it up to the proper level. Also,
When I flush it the handle dosen't have the same resistance as before and i have to repeat pulling the handle 3 or 4 times for it to release the water.

Where is the diaphram about that you mention that I should push it down?

Doug, April 2010

If it is a ball valve you can adjust a plastic screw to allow the cistern to fill up to the required level.
see pic here:
http://www.ultimatehandyman.co.uk/ball_valves/diaphragm_ball_valve_adjust.jpg
ther is usually a line inside the wall of the cistern for the required level. when it is at the required level it should flush properly.

tony, April 2010