Tektronix Phaser 840, Service Manual

Page: 92 / 207

Service Guide 81
If you see spattered ink on the edges of the printhead, the cap/wipe/purge
assembly’s gasket may be leaking during the purge cycle. A misaligned
printhead or a defective gasket may cause this. To verify the printhead
alignment, move the cap/wipe/purge assembly to its purge position and tilt
the printhead forward until the upper edge of the gasket touches the
faceplate. If the left and right sides touch at the same time, the printhead
side-to-side alignment is correct and the problem is probably due to the
gasket. If not, you need to readjust the printhead-to-drum gap.
If you see streaks or smudges of wax in the jet area of the printhead's
faceplate after a purge cycle, the cap/wipe/purge assembly wiper blade is
damaged and the cap/wipe/purge assembly needs to be replaced. In this
example, the blade has several defects; in most cases there is only one
smudge or streak.
4. Visually check cap/wipe/purge assembly wiper and gasket.
a. Open the front cover and remove the drum maintenance drawer.
b. If not in its standby position, lower the cap/wipe/purge assembly to its
standby position under the drum.
c. With a flashlight, closely examine the cap/wipe/purge assembly.
Inspect the gasket for defects and signs of separation.
d.
Tilt the printhead all the way back and raise the cap/wipe/purge
assembly to its purge position. Inspect the rubber wiper, especially at
the ends, for signs of separation. Gently probe the cap/wipe/purge
assembly gasket with fingers or blunt tool for signs of damage or
separation from the cap assembly. Replace if defective.
Faceplate showing streaks and smudges from a poor wipe