Removal and Replacement of the Delivery Drive Assembly

Replacement of the delivery drive is relatively straightforward. During reassembly it is critical that the plastic arm from the face up solenoid is properly engaged under the delivery drive swing arm. See the following sections for instructions on removing and replacing the delivery drive assembly.

Replacing the delivery drive assembly

Figure 1: HP Color LaserJet 8500 MFP video I/O connectors

1- Thumbscrews for video I/O connector

2- Remove three screws in recessed opening

Special instructions for the HP Color LaserJet 8550MFP models only.

Release the two thumbscrews to disconnect the video I/O connector. See Figure 1, call-out 1.

Remove three screws from inside the opening; the plate remains attached to the rear cover. See Figure 1, call-out 2.

Remove one screw, then the small rear lower-left corner cover.

The rear cover must be removed first.

1.Open the upper-right door and remove the three screws on the sheet metal tab. This is part of the rear cover.

2. Shut the upper-right door and remove the lower two screws that also attach the rear cover.

3. Remove the remaining 13 screws that attach the rear cover to the printer.

4. Remove the rear cover.

Figure 2: Lower air duct

Call-outs, two screws to remove duct

1. Loosen the thumbscrews and remove the formatter.

2. To remove the formatter pan, remove the five screws (two on the top and three on the bottom) then the five screws on the back of the formatter pan where the formatter slides in. Remember to disconnect the wiring guide from the front of the formatter pan.

3. The lower air duct has two screws holding it on; remove them and then the duct. See Figure 2, circled call-outs.

Figure 3: Small-black gear cover

1- Cover

2- Single screw to be removed

Remove one screw and carefully take the small black gear cover off the printer. See Figure 3, call-outs 1 and 2.

Figure 4: Location of carousel motor PCA board

1- Carousel motor PCA board

1. Remove the Fan 1 assembly. This is the larger of the two fans visible with the back cover removed. There are four screws.

2. Remove the carousel motor PCA board. See Figure 4, call-out 1.

Figure 5: Delivery drive removal

Call-outs - Close-up of swing arm in the correct position

Reassembly tip: The metal swing arm shown in Figure 5 must be above the plastic arm or the fuser access door will not shut properly. This arm is part of the face up solenoid. When the fuser access door is shut, the black gear pivots down and engages the delivery drive to provide drive to the diverter, feeder and top output assemblies.

How to remove the delivery drive assembly

1. Open the lower-left door (fuser access door). It must be open when reinstalling the delivery drive also.

2. Release the cable stays on the bottom of the delivery drive assembly.

3. Remove the seven screws that attach the delivery drive to the printer.

4. Lift the assembly up and off its tabs.

WARNING: Verify that the face up solenoid is in the correct position under the delivery drive swing arm.

© 2005 Hewlett-Packard