HP Laserjet 4000, 4050, 4100, 4200 Smeared Print
 In the HP Laser Jet 4200, 4100, 4000, 4050  if you have smeared print on the sides of the page, then most likely the fuser  film is torn. Typically, I get calls where the customer complains of grey or brown  pieces coming out the back, pages smeared print  on the page, and or noise like a clicking sound coming from the back of the machine.The film in the 4000, 4050, 4100, 4200 fuser  is just a light cylindrical film lubricated inside to slide over the heating element as it rotates. It doesn’t take much to tear it. The fuser film tends to drift to one side and rub against the bushings. Overtime it wears and eventually it will get a nick in it that leads to a tear soon after. When the HP laserjet 4200  printer was first introduced the film tore quite often due to one of the flanges in the fuser. The part has been updated over the years so that problem is fixed but tears still happen more often in this model than on most HP printers with the film technology resulting in smeared print.
HP Laserjet 400, 4050, 4100, 4200 Fuser Removal
1. Power off machine and unplug power and any communication cables.
2. Underneath the back door is a tray dust cover. Usually covered in dust. Grab it in the middle and pull out.
3. Lower the back door tray and with a flat blade screwdriver gently pry one of the side mounts out of its hole.
NOTE: With the door open if you look down on either side you will see post going into the side of the black frame.
4a. 4200: With the door removed you will see two blue clips on the fuser. Gently press up and pull the fuser out.
4b. 4100: With the door removed you will see two blue levers twist them  90 decrees to unlock and pull out.
4c. 4000: This machine has two screws. The screws are behind two plastic pieces. One above wear the power cord plugs in and the other is parallel  to it on the other side. Pull those out and you will see the two screws. If you have a duplexer  don’t worry about them because their already removed.
5. Once the fusers out turn it over and check the rollers and you’ll probably notice  half the one on top is missing.
6. Order in a new fuser and replace.
On newer models like the HP laserjet 4250 and  P4015  the fuser film is actually metal inside, which is more durable; an upgrade HP felt necessary to have with the speed of the machine. However, I’ve seen on several occasions the fuser  film to be slightly sluggish and not move at the same speed as the pressure roller resulting in smeared print, or what most customers call blurred print, because it usually comes out legible but for some reason just doesn’t look right. In extreme cases the film ceases to move at all resulting in paper jams as the paper hits the fuser. So for me, I’d like to see the old HP metal fusers  come back. Brother and other manufactures still use them and they don’t tend to have all the issues that HP fusers  have. But the HP laserjet 4000, 4050, 4100, and 4200’s are great and more often than not you will at least get 175,000 to 225,000 copies on  your fuser without any problems. With that being said if you have a HP laserjet 4000, 4050, 4100, and 4200 and you use it heavily your bound to run into the smeared print issue at some point.
Conclusion about the HP Laserjet 4000, 4050, 4100, 4200 Smeared Print
Like I’ve said before, ordering parts, like fusers, yourself can save you money because  service companies love marking up parts. I typically buy refurbished units as they are cheaper and with todays market, like toners, third party companies are producing a more durable part than what they were several years ago. But I would always recommend having a service tech come out and periodically clean your machine. Usually, when fusers  go out they have at least 50,000 to 100,000 copies on them so it’s always  a good time to have a tech come out and install the parts you ordered and check over the rest of the machine to avoid unwanted downtime when something else breaks. Hopefully, this article will help you troubleshoot and get parts on order for your HP laserJet 4000, 4050, 4100, 4200 smeared print issue.
Additional Printer Repair Articles can be found at : http://www.metrofuser.com/
