The paper feed problem afflicts the HP DeskJet 550C and 560C, DeskJet 520 and DeskWriter 520 printers produced between June 1993 and March 1994. The affected units have serial numbers beginning with 'US3' through 'US43.'
The problem seems to be that the rubber rollers become slick over time and then the paper doesn't always feed properly. Last year HP offered a free paper-feed cleaning kit to fix the problem. Try contacting HP at 800/656-2324 or 510/657-1473 (FAX) to find out if the free kits are still available.
(From: Allen E. Amey (email@example.com).)
Try contacting the manufacturer. I have heard that HP has a free kit for the 500 series printers. The kit dresses the rollers and is supposed to be a fix for the type of problem that you are experiencing. BTW, using alcohol can actually compound the problem by prematurely drying out the rollers.
(From: FaxRepair (firstname.lastname@example.org).)
I believe the only replacement part would be the entire paper pickup assembly which may need to be replaced because the gear train is damaged from ink having dripped onto it. Once the gear train is out of timing there is no known cure. Clean the rollers with rubbing alcohol and a soft cloth. If it doesn't pick up the paper after cleaning the rollers, then remove the entire print assembly and look for signs of ink on the gears at a location directly below the ink cartridge's home position. On a few occasions I have had success by flushing the gear mechanism with warm water to wash away dried ink.
(From: James E. Burke, Jr. (email@example.com).)
I fixed one for a friend a couple of months ago. Parts are not available (well, you can get them, but they're too expensive).
In the one I fixed, it was a broken plastic part that caused the misfeeds. To get to the part, I had to disassemble the whole printer.
If you decide to to this, check the two 'fingers' that are behind the print head when it's in the parked position. The hook on the tip of one of them was broken off. I found the broken part inside the printer and glued it back on with JB Weld (twice--first time backwards). The pair of 'fingers' are identical so you could probably swap parts from one of the other machines instead of attempting the repair of the "fingers".
(From: Paul Grohe (firstname.lastname@example.org).)
I have the same problem.
The rollers dry up and become glazed-over and smooth. You need to 'rough' them up.
Try sandpapering the wheels with coarse sandpaper (100 to 200 grit).
You'll need to trick the paper sensor. Take the cover off and lift-up on the black paper sensor lever. Then hold the piece of sandpaper firmly against the wheel and hit 'FF'. You'll need to do this repeatedly, as the wheels will only spin a sheets' worth each time.
Do this until the wheels feel 'sticky' again.
It also helps to keep the paper tray full at all times (but not overloaded).
Unfortunately, they'll never be like new.
(From: Frank Reid (email@example.com).)
I've had very good results cleaning the rollers with naphtha or mineral spirits, no sanding. It removes the glaze from the clay content of the paper, and makes the rollers softer.
(From: (Egiglious Giggles" (firstname.lastname@example.org).)
The thing I have come across, is the spring which is directly under the roller itself. The purpose is to allow tension on the roller for pulling the paper in one sheet at a time. If you look directly in the middle under the roller from the front there is a guide that is spring tensioned. You have to take the roller assembly apart to get to it. But, if cleaning the rollers doesn't do the job, this is probably the culprit.
(From: Tony Dunlap (email@example.com).)
The "Glaze" that gets on the rollers is often due to the rag content of many cheaper papers (especially "Recycled"). To clean the rollers: