image of a Ricoh printer

Black lines appearing on a Ricoh printer? Below is a scenario-by-scenario solution guide.

 

What causes black lines on paper when printing Ricoh?

Black lines appearing on Ricoh printers is a common quality issue, often caused by hardware contamination, consumables failure, or component wear. Different types of black lines (such as straight lines in a fixed position or randomly appearing thick lines) correspond to different faults. The following are specific solutions:

 

Ⅰ. Continuous black lines in a fixed position (appearing in the same location on every page)

  • Possible causes:

1) Scratches on the drum cartridge/photosensitive drum surface or toner clumps

2) Foreign matter or wear on the fuser roller

3) Contamination on the scanning platform glass/mirror (black lines appear during copying)

  • Solution:

1) Inspect the drum cartridge assembly

Remove the drum unit and observe the surface of the photosensitive drum (green or blue) in bright light.

If there are noticeable scratches, the drum cartridge is damaged and needs to be replaced. (Scratches cannot be repaired; continued use will result in continued black lines.)

If there are any toner clumps or oil stains, gently wipe them with a clean, soft cloth (do not use alcohol) to remove any debris. (Note: Do not touch the OPC drum surface directly with your hands to avoid fingerprints.)

2) Clean the Fusing Roller

After turning off the power, wait 10 minutes (the fusing roller is hot, so avoid burns). Open the printer’s side cover and locate the fusing unit (the hot component facing the paper output direction).

Inspect the fusing roller surface for any toner residue or foreign matter. Gently wipe it with a damp, soft cloth (for laser models).

If the fusing roller shows signs of wear (such as grooves), contact service personnel to replace the fusing unit.

3) Check the Scanning Unit (Black lines appear when copying)

Open the copier’s top cover and inspect the scanning platform glass for stains, scratches, or adhesive deposits.

Use an alcohol pad to wipe the glass surface, focusing on the edges (where tape residue often remains).

Check the reflective mirror under the glass. If dust is present, gently wipe it with lens tissue (to avoid scratching it).

 

Ⅱ. Randomly appearing thick black lines or bands

  • Possible causes:

1) Toner cartridge leakage or developer cartridge clogged

2) Paper dirty due to contamination of the paper feed roller

3) Laser printer malfunction (laser models)

  • Solution:

1) Troubleshooting toner leakage

Remove the toner cartridge and drum unit and inspect for signs of toner powder leakage.

If the toner cartridge is leaking, replace it with a new one (leaking toner can contaminate internal components; use a soft cloth to clean any remaining toner).

A clogged developer cartridge can cause toner to accumulate and randomly rub onto the paper. Disassemble the developer cartridge and clean it (recommended by a qualified professional).

2) Clean the paper feed and paper path

Wipe the paper feed and paper feed rollers with a damp, soft cloth to remove any toner or dust on the surface (this contaminant can transfer to the paper and cause black lines).

Check the paper for moisture or torn edges. Replace with dry, flat new paper and test.

3) Laser Inspection (Professional Operation)

If the above steps do not work, the laser may be contaminated or malfunctioning:

Dust on the laser lens of laser printers can cause beam scattering, resulting in black lines. Disassemble the machine and clean the laser (non-professionals are advised to contact a repair center).

Laser malfunctions require replacement of the corresponding component. This can be determined by printing a “Halftone Test Page” (laser problems will appear as irregular black lines).

 

III. Thin Vertical Black Lines (along the length of the paper)

  • Possible Causes:

1) Worn or foreign material on the drum cleaning blade

2) Contamination or deformation on the charging roller

3) Scratching of the drum surface by residual paper fibers

  • Solution:

1) Check the Cleaning Blade

The cleaning blade in the drum unit is responsible for removing residual toner powder from the drum surface. If there is foreign material or wear on the blade edge:

Remove the drum cartridge and carefully disassemble the cleaning blade (some models require tools). Use tweezers to remove foreign matter such as hair or paper scraps.

If there are gaps on the blade edge, replace the blade (or directly replace the drum unit).

2) Cleaning the Charge Roller

The charge roller is responsible for charging the photosensitive drum. Contamination can cause localized charging abnormalities:

Wipe the surface of the charge roller with a dry, soft cloth to remove toner powder residue (avoid using water or alcohol to prevent damage to the conductive layer).

If the charge roller is deformed (e.g., bent), replace it.

 

IV. Daily Maintenance to Prevent Black Line Issues

Use Consumables Properly: Prioritize genuine Ricoh toner cartridges and toner, and use high-quality compatible consumables.

Perform Regular Cleaning: Clean the printer interior monthly with compressed air, and inspect the toner cartridge and fuser assembly quarterly to detect contamination or wear.

Load Paper Correctly: Avoid using paper with frayed or wrinkled edges. Shake paper loose before loading to reduce fiber residue.

If black lines persist after self-treatment (especially if the problem is caused by hardware wear), contact a professional for inspection. Ricoh printer’ OPC drum, fuser assembly, and other parts are consumable. Regular replacement can effectively reduce print quality issues.