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5.4.3 Carriage Drive Belt Tension
The carriage belt connects the carriage drive motor mounted in the right end of the box with the carriage. Low
carriage belt tension can cause uneven character size and spacing or carriage stalling.
1. With the carriage in its leftmost position, use a spring gauge to deflect the center of the carriage belt.
Proceed to step 2 only if the force to deflect one side of the belt so that it just touches the other side of the
belt is not between 15 and 17 ounces (425-475 gms).
2. Remove the cabinet (see 5.5.1).
3. Locate the screw fastening the carriage idler pulley arm at the left end of the carriage drive belt to the left
pivot arm. Turn it to clockwise to increase or counter clockwise to decrease the belt tension. Repeat step
1.
5.4.4 Document Drive Belt Tension
The document drive belt connects the document drive motor mounted to the left side of the box with the rear
document drive roller. Low document belt tension causes uneven line spacing and document drive stalling.
1. Remove the cabinet (see 5.5.1).
2. Use a spring gauge to deflect the center of the document drive belt. Proceed to step 3 only if the force
measured to deflect the belt 1/16" (1.5mm) is not between 1.5 and 2.5 ounces (40 and 70 gms).
3. Loosen the 3 screws that fasten the document drive motor to the metal box. Do not loosen too much or the
jam nuts inside the box will fall off the screws.
4. Move the motor toward or away from the rear document drive roller to adjust the tension and tighten the
screws. Repeat step 2.
5.4.5 Carriage Left Home Position
1. Only use the following procedure if the LEFT OFFSET parameter is not displayed by 94 FUNCT. If it is, use
it to set left home (see 5.2).
2. Turn on power and insert a document to activate the carriage motor.
3. Loosen the set screw that fastens the drive pulley to the motor.
4. Push the carriage as far to the left as possible, then move it to the right about .020" (0.5 mm) and tighten
the set screw.
5. Check that the carriage tab slides into the left home sensor without binding. Bend the tab if necessary.
5.4.6 Wheel Guide
The wheel guide holds the carriage guide wheel against the box. A loose wheel guide can cause wavy
printing. A tight wheel guide can cause carriage stalling.
1. Remove the cabinet (see 5.5.1).
2. Loosen the screws on each end of the metal box fastening the wheel guide arms to the box.
3. With the carriage in its leftmost position, insert a .010" (.25 mm) feeler gauge between the guide wheel and
the box. Push the wheel guide against the guide wheel and insure that the wheel guide arms are
horizontal. Tighten the 2 wheel guide screws.
4. Move the carriage to its rightmost position and repeat step 3.
5. Adjust the envelope ramp on DP6’s below S/N 00588 (see 5.4.6).