Solving problems with Duplex Jams - DCP700/770, C75/J75
Parts for solving duplex jams on the DCP700/700i/770, or C75/J75, Including the following fault / error codes:
077-130 Duplex Out Sensor On Jam
077-118 Pre Regi Sensor On Jam (Duplex)
The most common cause of jamming in the duplex transport is the buildup of resistance on the parts in the Duplex Drive Belt area. The drive belt is located inside the front wall of the main transport drawer (the big drawer that has the fuser in it, see the photo below). The duplex transport spans all the way across the bottom of the drawer and includes the Duplex Upper Chute Assembly.
The twelve idler pulleys get gummed up, so they don't turn freely ... or the central holes in the pulleys get worn to the point where they're oblong instead of round. This puts stress on the duplex system until the one-way pin bearing in the center of the drive gear/pulley starts to slip and fail (this gear and the drive gear that drives it are located at the front far left corner of the bottom of the drawer)
We offer a few kits that address duplex jamming problems:
The most common cause of trouble is when the drive pulley/gear’s one way bearing fails. It is only spared in the OEM parts book as part of the much larger and much more costly assembly known as the Duplex Upper Chute Assembly (054K35936).
DC700DXDGK - Duplex Drive Gear Kit:
For the Idler Pulleys... there are two choices:
The cheaper choice is the original all-plastic pulleys (clean off the shafts good and add a drop of lubricant / gear oil on each pulley as you install them):
DC700DXIPK: Duplex Idler Pulley Kit:
OR ... there is an improved version of these pulleys that each have a pair of ball bearings in the center of each pulley... This is recommended for a very long life, especially if you run the machine heavily:
DC700DXIPBK: Duplex Idler Pulley / Bearing Kit:
Other components that wear out include the Drive Pulleys on the ends of the duplex transport rollers:
DC700DXDPK - Duplex Drive Pulley Kit:
Also check the oilite bearings that the duplex transport rolls ride on (check these for being oblong and clean them and the transport roll shafts thoroughly… replace if needed):
DC700DXTRBK - Duplex Transport Roll Bearing Kit:
Don’t forget the Drive Belt itself:
DC700DXDB - Duplex Drive Belt:
