8 years ago I had bought a Brother MFC 255CW printer. Since I use occasionally and carefully, it still functions very well. However, it is time to clean it since many particules (from paper sheets, not dust from outside) have already accumulated on the rollers. First time I will conduct a cleaning of this sort. The machine is very sensitive, I don't want to do any mistake. I will appreciate if you could give me a good source to clean paper carriage units of this kind of machines, such as paper feed roller, paper ejection roller and platten. And also cleaning chemicals to be used. Especially, I don't want to do any mistakes to unrelease the rollers from their gears in order to clean them thoroughly, so information about how to release rollers from the gears and also how to release the print head.