How to Remove and Replace the Print Carriage Belt on an Epson WF-3640 Printer

Question:
I have an Epson WorkForce WF-3640 printer. How do I remove the old belt from the print carriage in order to install a new one?

Answer:
Understanding the Printer Carriage Belt System

In the Epson WorkForce WF-3640, the carriage belt (also called the drive belt) is a toothed rubber belt that connects the carriage motor to the printhead assembly. It's responsible for moving the printhead smoothly from left to right. Over time, the belt can stretch, fray, or snap, leading to noise, misalignment, or printhead error messages such as Error Code 0x97, 0xEA, or "Carriage Jam."

Replacing this belt requires careful disassembly, as several printer components overlap the carriage system.

Step-by-Step Guide: Removing the Old Carriage Belt

Before starting, make sure the printer is unplugged and you have a clean workspace with small screwdrivers, tweezers, and a flashlight available.

1. Remove the Printer Cover and Scanning Unit

• Open the top scanner bed and locate the screws securing the scanner assembly.

• Disconnect the flat white scanner cable and the ADF cable carefully.

• Lift off the entire scanner unit to expose the main printer chassis.

2. Access the Carriage Assembly

• Manually move the printhead to the center (if it's still movable).

• Remove the right-side cover by unscrewing and gently detaching it. This will expose the carriage motor and part of the belt mechanism.

• The belt runs horizontally across the width of the printer, passing through the carriage motor gear on the right and attaching to the carriage slider in the center.

3. Remove the Belt from the Carriage Motor

• Note the belt routing before removal (taking a photo is highly recommended).

• Use tweezers or a small hook tool to lift the belt from the motor's pulley gear.

• Slowly slide the belt off the pulley-do not force it, as this can damage the motor gear teeth.

4. Detach the Belt from the Carriage Hook

• The belt connects to the back of the carriage with a small metal clip or hook.

• Using fine tweezers, gently lift and unhook the belt from this anchor point.

• Once detached, remove the old belt completely from the printer.

Installing the New Belt

1. Feed the new belt through the same path, aligning it with the track where the old belt sat.

2. Hook the belt back into the carriage anchor first.

3. Loop the other end of the belt around the motor pulley gear. Make sure the belt teeth align perfectly with the gear teeth-no twists or slack.

4. Test the belt movement by manually sliding the carriage back and forth. The motion should be smooth and even across the track.

5. Reassemble the covers and reconnect all cables securely before powering the printer back on.

After installation, run the printer's Printhead Alignment function through the maintenance menu. This ensures the belt tension and motion are properly calibrated.

Common Issues After Belt Replacement

• Error 0xEA (Carriage Jam): Usually means the belt is misaligned or twisted. Double-check the belt routing.

• Uneven printhead movement: Indicates the belt is too loose or the tensioner spring isn't properly seated.

• Grinding noise: May come from misaligned gear teeth or a missing stabilizer pin near the carriage slider.

Taking time to ensure all gears and rollers are seated correctly will prevent these issues and extend your printer's life.

Addressing printer issues can be a complicated affair due to the hands-on nature of the problems. Therefore, we're not able to provide remote troubleshooting, suggestions, or support for printer repairs. We offer an in-person evaluation and repair service through our local diagnostic facility (https://bchtechnologies.com/printer-repair-service). Given the high demand, we operate on a first-come, first-served basis, and it may take a few weeks before we can accept a drop-off. Our services cover both complete printer repairs and specific part replacements, with clear guidance on next steps.

However, we recognize that our rates might not be the most economical. For that reason, we highly recommend exploring self-repair options through online research. You can start by visiting our YouTube channel (https://youtube.com/@bchtechnologies) and using the search icon next to "About" to find relevant tutorials. With hundreds of repair videos produced over the past nine years, this is the fastest way to locate specific guidance. YouTube may also suggest other helpful videos from different creators that could assist you.

Thank you once again for your question and your continued support of BCH Technologies. We hope these detailed steps help guide you through the belt replacement process and get your Epson WF-3640 back in smooth working order.