Few things in life are as frustrating as trying to print a long document and having the printer jam after every couple of pages. Most chronic paper jams are caused by normal wear and tear and are correctable. The trick is locating the source of the problem. Let's take a look at some common causes of paper jams and ways to resolve them. Keep in mind that I will be explaining how to troubleshoot these issues on a Hewlett-Packard LaserJet 1100. Each model of HP laser printer is a little different, so instructions in this article may not apply exactly to your printer.
Sometimes you might need a professional
Before I begin, I’d like to stress that this article is intended to assist with basic printer repair and cleaning. If you’re unsure of your ability to perform such printer maintenance, or if performing such maintenance will void the printer's warranty, contact a qualified service professional or the manufacturer instead.
Worn pickup roller or weakened separation pad spring
By far the most common area for paper jams on the LaserJet 1100 is in the paper tray slot. Generally, this is caused by the pickup rollers wearing out. Pickup rollers are plastic rollers with a rubber surface. You can see an example of a pickup roller in Figure A. Under normal circumstances, this rubber coating grips the page and moves it along through the printer. Over time, though, the rubber surface on the rollers gets smooth and shiny and is no longer able to grip the paper effectively.
|This pickup roller assembly has been removed from the printer. The pickup roller itself has a rough rubber coating that grabs the paper.|
You can tell if a roller has become worn just by looking at it. A worn roller will usually either have a flat spot on it or appear shiny. For complete instructions on cleaning and replacing the pickup roller on an HP LaserJet 1100, check out this page on Hewlett-Packard's Web site.
The pickup roller doesn’t work all by itself. The separation pad assists it. The separation pad is nothing more than a piece of plastic that’s pressed up against the pickup roller by a spring. In Figure B, the pickup roller has been removed so that you can see the separation pad.
|The separation pad is held against the pickup roller by a spring.|
The separation pad’s job is to apply tension to the paper so that it is pressed firmly against the pickup roller. If the spring becomes weak, the separation pad won’t exert enough force on the roller and paper jams will occur.
The first sign that this spring is weakening will be that the printer will grab more than one piece of paper at a time. The problem will gradually become worse until the printer tries to grab the entire stack of paper, which of course causes a jam. This problem occurs because the spring isn’t exerting enough force on the pickup roller to prevent more than one piece of paper from being grabbed at a time. For complete instructions on replacing the LaserJet 1100 printer's separation pad, check out this page on Hewlett-Packard's Web site.
Prevent undue pickup roller and separation pad wear
The pickup roller and separation pad problems happen most commonly with printers such as the HP LaserJet 1100 because of the vertical paper feeder. The vertical position of the paper feeder means that gravity is exerting downward force on the paper when the printer is trying to feed it. This places excessive pressure on the separation pad. Printers that use horizontal paper feeders can also have this problem, but it generally takes a lot longer for the spring to wear out.
You can minimize the strain on the separation pad by never filling the paper feeder more than two-thirds full and by refilling the paper feeder when it is down to one-third of its total capacity. I also recommend fanning the paper before loading it and doing a quick check to make sure that the corners aren’t bent. You can also help prolong the life of the separation pad and the pickup roller by not running exceptionally heavyweight paper through the printer.
Foreign matter inside the printer
Another common cause of paper jams is foreign matter inside the printer. Foreign matter can consist of excessive paper dust or toner dust. When I’ve worked on severely damaged printers, I've found things like paper clips and staples inside of them. These objects tend to get caught between gears or wedged in the fuser. The fuser rollers are made of wax and will crack very easily if a foreign object becomes jammed in them. Once the fuser is cracked, the printer will have poor printing quality and paper jams may become more persistent.
The most common foreign matter that I've found in printers is loose screws from the printer. Some laser printers tend to be hard to work on, and if a technician drops a screw and isn’t able to retrieve it easily, the technician may just let leave it there. But these loose screws can cause an excessive amount of damage to a printer.
Likewise, printers have a lot of moving parts. If a part isn't screwed down tightly, there is high potential for breakage or for more paper jams. Obviously, if a plastic piece breaks because it isn’t screwed down tightly, it can further complicate the issue of paper jams and other internal damage.
Getting replacement parts and performing repairs
There are a couple of tricks to performing the repairs. First, HP sells printer maintenance kits for most of its printers. These kits replace the rollers, separation pad, and other components that wear out over time. You can purchase replacement parts directly from Hewlett-Packard or from a number of Web sites and office supply companies. A quick query with your favorite search engine should list more than enough sources for parts.
Another thing to remember is to be very careful when you work on printers. If you take a screw out, pay close attention to where that screw came from and make sure that it goes back into the correct place. Use a magnetic screwdriver to avoid dropping screws. If you do drop a screw, take the time to get it out, even if that means further disassembling the printer.