Those 4/600 Laserwriters are great little printers. I've been using them for years without any problems.
Smudging is usually caused by a defective or damaged toner cartridge. Pull out the cartridge and make sure there aren't any pieces of paper lodged in the spring loaded drum cover. If you move the cover you'll see the drum as that shiney greenish cylinder. Do this over some newspapers and wear old clothes since even a small amount of toner can create a real mess.
How old is the cartridge? Is it an original Apple or HP cartridge, or was it a refilled cartridge? If the cartridge is just old or refilled, then you probably need a new cartridge.
Smudging is usually caused by a defective or damaged toner cartridge. Pull out the cartridge and make sure there aren't any pieces of paper lodged in the spring loaded drum cover. If you move the cover you'll see the drum as that shiney greenish cylinder. Do this over some newspapers and wear old clothes since even a small amount of toner can create a real mess.
How old is the cartridge? Is it an original Apple or HP cartridge, or was it a refilled cartridge? If the cartridge is just old or refilled, then you probably need a new cartridge.