459Stacker ProblemsThe power stacker augments the paper feed system of the printer. The most frequently occurring problems in the paper feedsystem are paper jams. Because of the electromechanical nature of the system, other problems that can occur are worn orpoor electrical connections and cabling, worn or defective feed motors, worn or damaged mechanical components, or incorrectinstallation of the stacker assembly. The inspection and tests below will allow you to make sure the stacker is operatingcorrectly. Table 7 shows some of the problems that can occur with the power stacker and the page where you can find thetroubleshooting procedure.Stacker First InspectionNOTE: Do this inspection before doing any other troubleshooting or repair work on the power stacker.1. Verify that the elevator seats all the way down on its left and right hand stops without having to force it down or hold it inposition.a. If necessary, correct improper seating by moving the elevator all the way down to the bottom of its travel and loosen thedrive belt pulley on the side(s) that does not seat properly.b. While holding the elevator in the fully down position, tighten the pulley setscrews.c. Verify that the elevator seats against both stops.ATTENTION While doing the next step, make sure the idler rollers do not interfere with the drive rollers as they move along thedrive shaft.2. Verify that the friction washers do not bind on the driver shaft.a. Manually retract and hold the idler roller shaft so the paper throat is open. While the throat is open, slide the drive rolleron one end toward the center of the shaft.b. Wipe a finger across the shaft and check for lubricant.c. Release the drive roller and allow it to spring back into position along the drive shaft.d. Repeat substeps a, b, and c on the other end of the driver shaft.e. Verify that there was no oil on the shafts.f. If the drive rollers returned to position without hanging up on the shaft, they are not binding and are OK.g. If there was oil on the shafts or the drive rollers hung up on the shaft, replace the roller drive shaft (page 491).3. Power on the printer and move the stacker elevator up and down using the ELEVATOR UP and ELEVATOR DOWN keyson the rear operator panel.
