If the picture has suddenly gone pink, have a look at the CRT base printed circuit board. There are usually three high wattage cathode resistors that get quite warm in operation.Its a favourite place for dry joints.
Good advice from Gemma. But...if you do this, make damn sure that capacitors are discharged either by leaving the set unplugged for a few days or using a discharging device. You will be working in an area where voltages are ramped up way higher than mains. Get this wrong and... well! Don't want to preach but this is NOT something for someone unskilled to attempt.