Fixing the HP LaserJet P3005 Grinding Noise
- By Jay Krause
- Mar 01, 2011
Following in the footsteps of its predecessor, the P3005 has picked up a similar noise that is creating a lot of problems for techs in the field. One difference between the P3005 and the LJ2400, its predecessor, is the complexity of this problem.
It starts in a familiar way: The fuser and the bushings wear out, allowing the lower pressure roller to sink down into the fuser. This allows the teeth of the drive gear to pull away from the drive gear to the fuser. As you would expect, when gears don’t mesh properly, it leads to damage, and “Ouch!” — we hear that same wonderful grinding noise. In some cases, it’s a simple fix, but in other cases, a more complicated repair is required. This article will instruct you on a common repair that fixes the problem.
Let’s take a look at the source of the grinding noise in the P3005 series and how to fix it, step by step.
Cause 1: The gears attached to the fusing drive assembly
The most common cause of the noise is the four gears that are attached to the fusing drive assembly. These four gears sit above the fuser and attach to the fusing drive assembly but are separate from the fuser drive. Changing these parts usually ends the noise. See Figure 1.
There is a 17x17-tooth double gear (RU5-0958), a 20x20-tooth double gear (RU5-0956), a 19-tooth gear (RU5-0959) and a 20-tooth gear (RU5-0957). All these gears are in a handy kit. We’ll provide you detailed instructions on how to replace these.
1. Remove the toner cartridge and cassette tray.
2. Remove the rear cover. To pull the rear output tray all the way down, you have to release the two door stops; this will allow you to access the two screws holding the rear cover. See Figure 2.
3. Remove the two screws, then lift the cover from the bottom to disengage the alignment tabs at the top. Pull the cover away from the printer. See Figure 3.
4. Remove the I/O cover. Tilt the cover to clear the tabs on the right side of the cover. See Figure 4.
5. Remove the duplex inlet guide. There are two tabs that get released; then it pulls right out of the back of the printer. See Figure 5.
6. Disconnect the fuser power cable on the left-hand side. See Figure 6.
7. Disconnect the cables on the right-hand side of the fuser. There is one purple and one yellow cable. See Figure 7.
8. Remove the four screws holding in the fuser. There are three self-tapping and one grounding screw.
9. Now tilt the fuser slightly toward the rear and pull it away from the machine. See Figure 8.
10. Remove the 17x17-tooth double gear (RU5-0958) first; there is a tab that you release so this pulls right off. See Figure 9.
11. Now you can remove the 19-tooth single gear (RU5-0959). See Figure 10.
12. Remove the fuser thrust stopper (RC2-0657) that holds the 20x20-tooth gear in place. (If this is missing, it will cause quite a grinding noise.) Remove the 20x20-tooth gear (RU5-0956). See Figure 11.
13. Remove the 20-tooth gear (RU5-0957). See Figure 12.
Delivery drive gears
While not as common, there is another cause for the grinding noise: the delivery drive gears. Three larger gears buried up on top of the delivery area are driven off of four gears by a pendulum gear that hangs down in between the two double gears. The pendulum gear sits over a big 65-tooth gear; then you have a 43-tooth gear and a 31-tooth gear that will sometimes take care of this issue if replaced. The 31-tooth gear is the gear that directly meshes with the output roller. We’ll also give you instructions on how to replace these gears.
1. To remove the formatter board, open the metal formatter cover and lift it up and off of the hinges. Disconnect the three cables. There is one blue-and-orange cable, one black cable, one ribbon cable and six screws that need to be removed. Now pull the formatter from the left side slightly out and lift it away from the printer.
To remove the engine control board, remove the front right cover. Remove the two screws from the rear of the cover and rotate it toward the front of the printer. Remove the control panel. There is one screw in the front of the panel and a grounding wire over the fan that need to be removed. Open the toner door and lift the control panel to the right, then feed the black cable through the frame. When reinstalling, use the pin on the panel to reinstall correctly. Remove the left-side cover. There are two screws at the bottom of the cover that need to be removed. Then, from the rear of the printer, push on and release the tab; the rotated cover should pull away from the printer.
2. Remove the top-right cover. There is one screw to be removed, and it lifts away from the machine.
3. Remove the top cover. There are four screws that need to be removed: two on the right side and two on the left side.
4. Remove the fan. Remove the two screws and disconnect the cable from the ECU.
5. Disconnect the 10 cables from the ECU. Unroute the toner door switch (this is hardwired to the ECU).
6. Remove the two black screws and remove the I/O plate.
7. Disconnect the laser scanner cable.
8. Disconnect and unroute the two cables from the rear top of the printer.
9. Remove the seven black screws from the ECU pan and the one grounding silver screw (there is a star stamped into the frame above this) to the right of the AC receptacle.
10. When reinstalling the ECU, remember to get the on/off switch into the rod slot.
11. From the top of the ECU, rotate the board out and away from the printer; this will expose the ribbon cable from the laser scanner. Disconnect this from the laser scanner assembly. Route the cable through the frame. Now slowly rotate the board out and away from the machine. This will expose a ribbon cable near the bottom of the ECU. Disconnect the cable from the ECU and remove the ECU from the printer. See Figures 13-18.
12. Removal of the fuser drive assembly (RM1-3746). See Figure 19.
There are five screws: one in the center, two on top and two on the bottom of the assembly. Remove these screws. At first, it appears that the main drive is going to have to be removed (which is a lot more work), but we figured out an easier way to get the assembly out and reinstalled. One gear has a clip that you need to release. Once you’ve released the clip and the gear slides off, remove the drive. All four gears left on the drive will slide off as you remove the frame of the drive. They are all keyed, so they will only go on one correct way. Pay attention to how they sit on the drive. This is all included on the fuser drive assembly (RM1-3746), which includes the frame and the five gears. See Figure 20.
13. You will have to set the gears in the body and slide the drive into the gears in order to get the drive back into the machine without removing the main drive assembly. See Figure 21.
14. Figure 22 shows the output assembly, exposing the last three possible gears that can cause this noise. There are three gears and a pendulum assembly that you will expose. There is a 43-tooth gear (RU5-0955), a 31-tooth gear (RU5-0960), a 65-tooth gear (RU5-0962) and a pendulum (RM1-3748).
15. Remove the fuser drive motor (RK2-1489). There are two screws you have to remove.
Also unroute the motor cable and remove the motor. See Figures 23 and 24.
16. There are three self-tapping screws on the left side and the right side that have to be removed. Unclip the cable holders to move the cables out of the way. See Figures 25, 26 and 27.
17. There is a metal strap that is held on by one screw on the rear of the machine that has to be removed. See Figure 28.
18. Unroute the wires. See Figures 29 and 30.
19. You will have to flex the frame to remove the output. There will still be one purple cable connected to the output; just rotate it and set it on top of the machine. Now you will expose those three gears and pendulum. Note the plastic assembly is not available; you can replace the output roller, but the black plastic housing you remove to expose the gears is not available, as it is considered part of the frame of the printer. See Figures 31 and 32.
The noisy P3005 has plagued service technicians for quite a while. We have presented the two most common solutions that create a quieter P3005. We have not experienced an issue with the fusing assembly or the fuser drive assembly at this point, but we will keep you posted.
Contact Jay Krause at www.partsnow.com.
This article originally appeared in the March 2011 issue of Recharger.
Jay Krause is a member of the technical support team at Parts Now! Over the past four years, Krause has helped solve the most baffling printer breakdowns for companies with as many as 1,000 technicians to as few as one. He authors trade journal articles and trains internal technicians.