Remanufacturing the Lexmark T520 Series Toner Cartridge
First introduced in June 2001, the Lexmark T520 series is based on the Lexmark 4520 1200-dpi engine. Depending on the model, the print speed is from 20 to 25 pages per minute.
Apparently, to cut costs, Lexmark is no longer using a drum cover on its cartridges. See Figure 1. Let your customers know this so that maybe they will take a little better care of the cartridge for you. Since that probably won’t happen, aftermarket drum covers should be available early this fall.
These cartridges have anti-recycling devices installed in the Prebate cartridges that will not allow the cartridge to be used again until the chip board is replaced. As with other Lexmark cartridges, the non-Prebate cartridges work without replacing the chips. At this time, replacement chips are available that are either single-use or multiple-use. If you are not going to get the cartridge back, use the cheaper, single-use chip. If you are, use the multiple-use chip. See Figure 2.
Note: As of May 2002, Lexmark T520, T620 and IBM Infoprint 1120/25/30/40 printers have shipped with new firmware that renders useless the first replacement chips that were developed. In those machines, you will get "Error 32 Unsupported Cartridge." By the time you read this, the new aftermarket replacement chips should be available, but it is good to keep in mind that Lexmark has made the change, and may again. Lexmark even has an update available on its Web site so that the older printers can be "upgraded" to include this change! The complete information is as follows:
To check the printer’s firmware, print out the "Printer Information" page. This is accessed through the Utilities/Printer menu. Printers that were manufactured before May 2002 have firmwares of 84.40xx and 84.50xx. If the printer has a firmware of 84.61.xx, that machine has the newer firmware. The manufacturing date is also on the manufacturing label located on the back of the printer.
Again, by the time this article is published, new chips should be available and the older chips should be out of circulation. This information is just for reference, in case you get an "Error 32" when remanufacturing these cartridges. Check with your supplier to make sure you have the correct version of the chip. This is also further proof that we cannot let down our guard when it comes to Lexmark. If these printers are not going to be replaced by a newer model anytime soon, then we will probably see another "upgrade" to the firmware.
The encoder wheel in these cartridges does not control the toner yield as in past cartridges; the chip does this. The encoder wheel only indicates if the cartridge is a Prebate or not. See Figure 3 for the two versions. The non-Prebate wheel in our cartridges is made of white plastic, while the Prebate is black.
For cartridges used in MICR-only machines, make sure that the chip you are using will work. MICR is also strictly a chip function. If the cartridge is to be used in other than a Lexmark machine, the chip is different again. So far, IBM and Toshiba are also using this engine. Again, check with your chip supplier to make sure that the chip will work with your machine.
All that being said, these cartridges have a huge profit potential (see below). Even with the extra cost of the chip, and the need to be careful about which machine it goes into, it is still worthwhile to remanufacture. The cartridge design is based on the older Optra S. Out of all the Lexmark-designed cartridges, this is by far the best. It is easy to do with very few headaches.
The Lexmark part numbers for these cartridges are as follows:
o Prebate 7.5K* cartridge: 12A6830, list $179.00**
o Prebate 20K* cartridge: 12A6835, list $421.00**
o Regular 20K* cartridge: 12A6735, list $469.00**
*Yield based on 5 percent coverage.
** List prices current as of July 15, 2002.
As with the Optra S machines, the PCR is not in the cartridge. It’s in the printer, and is rated for 300,000 pages. The wiper blade inside the cartridge has an external felt brush that keeps the PCR clean.
It should also be noted that because of the play between the toner hopper and the OPC drum, a shipping lock should be installed in every cartridge. This holds true even if you are going to hand-deliver the cartridge.
Cartridge/machine troubleshooting and test printing information is at the end of this article.
- Toner-approved vacuum
- 2A small, flat-head screwdriver
- A Phillips-head screwdriver
- Needle-nose pliers
- Spring hook
- Razor blade
One bottle of 4069/4520 600g toner for 20k cartridge. Use 250g for 7.5k cartridge.
Drum-padding powder (Kynar). Do NOT use Zinc Sterate on these cartridges!
Long life OPC drum (optional)
Aftermarket drum cover
Can of compressed air
1) Vacuum the exterior of the toner cartridge.
2) Place the cartridge on the bench with the drum side up (label face down), and the toner supply toward you.
3) With the needle-nose pliers or a spring hook, remove the two springs from each end of the cartridge. See Figure 4.
4) Note that there are two posts from the hopper that fit into the cartridge shell. Pull the shell out to release the posts, and lift up the hopper so that the posts are free. See Figure 5.
5) Slide the hopper to the right, and remove from the cartridge. Pull it out so that the large white bearing comes free. Place the hopper aside. See Figure 6.
6) Remove the e-ring from the small helical gear end of the drum axle. There is no need to remove the other e-ring. See Figure 7.
7) Slide the drum axle out of the cartridge. Hold the small helical gear while pulling it out so that the drum is not damaged in the process. Note the location of the spring. See Figures 8 and 9.
8) Gently lift the drum and drum washer up and out of the cartridge, and place in a light-protected area. Be careful not to lose the spring — its purpose is to keep the drum from rotating backward. See Figure 10.
9) Remove the wiper blade by removing the two screws from the wiper blade. See Figure 11.
10) Turn the cartridge so that the waste bin is face up. Take a razor blade and cut the foam seal that runs along the back edge of the wiper blade so that it is separated from the cartridge. Make sure to cut along the plastic and not the wiper blade. See Figure 12.
11) Hold the cartridge so that it is upright (standing up with the waste bin on the table). With one hand, hold the laser shutter open, and with the other hand, remove the wiper blade. See Figure 13.
Note 1: The OEM wiper blade has the PCR cleaning assembly attached to it. It cannot be removed from the blade without damaging it. Some new replacement wiper blades come complete with this assembly attached.
Note 2: The "starter cartridges" that come with a new printer do not have the PCR cleaning assembly on the wiper blade.
12) Make sure that the two end foams are clean and in their proper place. See Figure 14.
13) Pad the new wiper blade with Kynar padding powder. Replace the blade and two screws into the cartridge. See Figure 15.
14) Place a piece of tape along the edge of the wiper blade. If the tape does not stick well, clean the area with alcohol. It is very important to get a good seal with the tape, otherwise the cartridge will leak. Trim away any excess tape. See Figure 16.
Note: Be careful not to allow any tape into the laser port opening!
15) Remove the recovery blade entirely, and shake the toner out of the debris cavity into the garbage can and vacuum clean. Removing the recovery blade allows greater access to the waste toner. See Figure 17.
16) Install a new recovery blade with a recovery blade insertion tool. Use of this tool will keep the blade from becoming damaged. See Figure 18.
17) With a small common screwdriver, gently pry off the encoder wheel. Pry it off from the center shaft so that the wheel does not become damaged. Place the wheel in a safe place. Remember, this wheel tells the cartridge what type of cartridge it is, Prebate or non-Prebate. The chip tells the machine what type of yield the cartridge has. If this wheel becomes damaged, it must be replaced with a wheel from another cartridge. See Figure 19.
18) Remove the doctor blade spring by pressing down on the center of the spring. See Figure 20.
19) On the left (fill plug) side of the static roller, there is a small metal bushing. Take a small screwdriver, and turn the bushing up so that the tab on the bushing is facing up. This will release the bushing and static roller. See Figure 21.
20) Remove the static roller and bushing. See Figure 22.
Note: Always remove the doctor blade spring before removing the static roller. Failure to do this will allow the doctor blade to slide down from its original position.
21) Remove the fill plug from the hopper. Pry the plug out of the base next to the hopper. The fill plug is also a breather cap. It is best to remove both sections at once and to clean them from the outside. These plugs tend to leak if they have been separated. See Figure 23.
22) Vacuum the toner hopper clean.
23) With a cotton swab dipped in alcohol, clean the static roller seals located on either end of the static roller section. These seals are made of a white plastic. Also, clean the electrical contact that touches the static roller shaft. See Figure 24.
24) Carefully vacuum or blow off the static roller. Be careful not to touch the roller with your hands, or to damage this roller in any way.
25) Inspect the inner and outer retaining blades (black Mylar). If they are bent in any way, you must replace them or they will leak. See Figure 25.
26) Install the white washers on the static roller, and the bushing on the non-keyed end of the static roller. See Figure 26.
27) Place the keyed end of the static roller into the cartridge and install the roller. Turn the bushing so that the tab is facing down. This will lock the roller in place. See Figure 27.
28) Install the doctor blade spring. See Figure 28.
29) Fill the hopper with the appropriate amount of toner. Remember, the amount of toner that can be placed in the cartridge is controlled by the chip. Use 600g for the 20k cartridge, and 250g for the 7.5k cartridge. Install the fill plug. See Figure 29.
30) Install the encoder wheel.
31) Remove the drum from the light-protected area, and blow off any remaining toner with canned compressed air, and lightly coat with the drum padding powder (Kynar). Do NOT use DPP (Zinc Sterate); this powder will ruin the wiper blade.
32) Place the OPC drum into the cartridge with the small helical gear on the non-contact side of the cartridge. Make sure that the spring is in the proper position. See Figure 30.
33) Install the drum axle pin into the small, white-gear side of the drum. The axle must be installed this way to prevent the axle from bending and damaging the drum ground contact located inside the drum. See Figure 31.
34) Install the e-ring on the end of the axle. See
35) Remove the old chip with a pair of pliers, and install the new chip.
36) Take the toner hopper and install it left side first. Make sure the left-side post and the white bearing are in their proper slot. See Figure 33.
37) On the right side of the cartridge, pull the cartridge shell out so that the right side post falls into its slot. See
38) With the spring hook, replace both springs onto the toner supply chamber. See Figure 35.
39) Re-install the static roller drive gear. See Figure 36.
40) You must now install a shipping lock. Use this lock even if you are going to hand-deliver the cartridge. It will prevent the toner hopper from coming in contact with the OPC drum and causing damage to either the drum or the static roller. Press the two red tabs into the sides of the cartridge as indicated in the picture supplied with the lock.
When packaging the cartridge, make sure you include a new felt wand.
Replace the wand in the machine by lifting up the external plastic cover located over the fuser assembly. Unlike most other printers, this area cannot be reached from the inside of the machine!
Dirty Primary Charge Roller: Located inside the printer, this will show up on the test page as vertical gray streaks down the page or as a gray background throughout the page.
Scratched Drum: This is shown by a very thin, perfectly straight line that runs from the top to the bottom of the test page.
Chipped Drum: This will show up as a dot or series of dots that repeat two times per page. Any drum defects will repeat three times per page based on the drum circumference of 5.2 inches.
Light Damaged Drum: This will show up as a shaded area on the test print that should be white. Again, this will repeat three times per page.
Bad Wiper Blade: This will show up as either a gray line approximately 1/8 inch thick, or as shading across the entire page. In either case, there will be a film of toner on the drum surface.
Weak Doctor Blade Spring: This will usually show up as shaded areas on one or both sides of the page.
Machine Error Codes
31 — Defective print cartridge. We have no idea what they mean by this. It is possible that the cartridge has too much torque and is loading down the gear train, but we just don’t know.
32 — Unsupported print cartridge. (Wrong chip, encoder wheel combination or bad chip.) If this happens immediately upon cartridge installation, either there is a bad contact to the chip, or the chip is bad. If the machine cycles and then the message appears, then the wrong encoder wheel is installed.
80 — Scheduled maintenance (300,000 page).
88 — Toner low.
200-260 — Various paper jams.
917 — Bad transfer roller.
920, 921, 922, 923, 924, 925 — Fuser errors.
929 — Toner sensor error. This could be a bad developer drive assembly, bad cartridge or bad chip reader in the printer. Or, the gear opposite the encoder wheel shaft is out of place.
930, 931-935 — Print head (laser unit) is bad.
Taking Test Prints
1) Press the "MENU"(2) key until "Utilities Menu" displays.
2) Press "SELECT."
3) Press "MENU"(2) one time for a demo page.
4) Press "MENU"(2) two times to print the menus.
5) Press "MENU"(2) three times to print the fonts.
6) Press "SELECT" again and the selected page will print.
The Menu page also contains the printer page count, toner level, cartridge serial number, cartridge size, if it is Prebate or not, and the cartridge type (normal, MICR, label).
Contact Mike Josiah and the technical staff of Summit Laser at (631) 218-8376, fax (631) 218-3285 or visit www.summitlaser.com.
This article originally appeared in the September 2002 issue of Recharger.