Epson ET-8550 Star Wheel Assembly Missing: Parts, Screws, Springs, and Installation Guidance

Question

I have two Epson ET-8550 printers that were purchased from a local discount warehouse outlet. Both appeared almost new, with very low print counts, but both had issues when I received them. The first ET-8550 was eventually repaired after checking the printhead and fixing the main board power transistors. I had also replaced Fuse 1, which seems to have been damaged by the failed transistors. That printer now prints well, but it has always had a problem advancing or exiting the paper correctly at the bottom of the page. We had discussed the PE sensor before, but I chose to work around the issue by printing on oversized paper and trimming the bottom afterward.

The second ET-8550 also had a very low page count. I was able to get it working using your printhead-starting method with suction on the ink feed tube to the printhead. However, this printer also has the same problem at the end of the print, where the paper does not advance or exit properly. It also works when I use oversized paper.

After watching your ET-8550 DTF conversion tutorial, I noticed the part where the star wheel assembly is removed. I checked both of my ET-8550 printers and found that neither one has the star wheel assembly installed. My Epson ET-8500 does have that assembly, so I now suspect the missing star wheel assembly may be related to the paper-exit problem on both ET-8550 printers.

Do you have two ET-8550 star wheel assemblies available for sale? If so, can you include the screws, mounting springs, and grounding springs? Also, do you have better instructions for installing the star wheel assembly, and can it be installed without removing the printhead or carriage assembly?

Answer

Yes, we do have a way for you to locate and purchase the ET-8550 star wheel assembly. The best starting point is our ET-8550 exploded parts diagram and repair reference guide. You can find it here: ET-8550 Exploded Parts Diagram and Repair Reference Guide [https://bchtechnologies.com/products/et-8550-et8550-exploded-parts-diagram-repair-reference-guide-annotated-edition?_pos=1&_sid=1a9d5e5cc&_ss=r]. Once you are on that page, look for the star wheel assembly in the diagram and click on it. That will be the most accurate way to identify the correct part for the ET-8550.

However, we are not able to include the screws, mounting springs, or grounding springs with the star wheel assembly unless those parts are specifically listed as part of the item being sold. In many Epson assemblies, the screws, tension springs, small mounting hardware, and grounding springs are treated as separate hardware pieces. When printers are disassembled for parts, those small pieces are often removed, misplaced, damaged, or not included with the larger assembly. For that reason, if the listing is for the star wheel assembly only, you should expect that it does not include the screws, mounting springs, or grounding springs.

The grounding spring is not just a random piece of hardware. On paper-exit assemblies, metal star wheels can build or carry static charge, especially when paper moves across them repeatedly. Grounding hardware helps control static and can also help reduce odd paper-handling behavior. If the star wheel assembly is installed without the correct spring, screw, or grounding contact, the assembly may physically sit in place but still not behave exactly like the original factory configuration.

Your observation makes sense. The ET-8550 uses star wheels to help control the paper as it exits the printer, especially near the bottom portion of the page. When the trailing edge of the paper leaves the main feed rollers, the printer still needs to guide and stabilize the sheet so the final portion of the print lands correctly. If the star wheel assembly is missing, the printer may lose proper control of the paper near the end of the sheet. That can cause bottom-margin printing issues, skewing, delayed paper exit, incomplete advancement, smearing, or the need to print on oversized paper and trim afterward.

Since both of your ET-8550 printers have the same missing assembly and the same end-of-page advancement issue, the missing star wheel assembly is a very reasonable suspect. It is unusual that both printers arrived without it, especially if they appeared to be in original boxes with sealed Epson ink and no obvious signs of disassembly. However, since they were returns from a discount warehouse source, it is still possible that they were previously opened, partially serviced, used for conversion attempts, returned after parts were removed, or mixed with incomplete units. Sometimes returned printers look almost new externally but may have been handled internally before being resold.

It is also possible, though less common, that a production variation or missing-factory-assembly issue occurred. However, because your ET-8500 has the star wheel assembly and both ET-8550 printers show paper-exit symptoms consistent with missing paper-output control, I would treat the missing assembly as a likely mechanical cause rather than assuming Epson intentionally omitted it.

As for installation instructions, we may have related videos in our YouTube library, but I do not want to point you to the wrong video from memory. With over nine years of repair work and more than 1,200 videos on our channel, there is a good chance we have covered something related to ET-8550 paper-exit parts, star wheels, output assemblies, DTF conversion, or top-frame disassembly. However, YouTube search will be more reliable than my memory.

To search within our channel, go to BCH Technologies on YouTube [https://youtube.com/@bchtechnologies]. Once you are on the channel homepage, click the magnifying glass icon near the top right side of the channel menu and search terms such as "ET-8550 star wheel," "ET-8550 DTF conversion," "ET-8550 paper exit," "ET-8550 output roller," "ET-8550 disassembly," or "ET-8550 paper feed." Searching directly inside the YouTube channel is usually the most effective method because it limits the results to our videos.

You can also use Google by typing your keywords followed by site:youtube.com/@bchtechnologies. For example, you could search for "ET-8550 star wheel site:youtube.com/@bchtechnologies" or "ET-8550 DTF conversion star wheel site:youtube.com/@bchtechnologies." Google may show fewer results than YouTube's internal search, but it can still be helpful if you are looking for a specific phrase.

Regarding whether the star wheel assembly can be installed without removing the printhead or carriage assembly, the honest answer is: maybe. It may be possible to install it without fully removing the printhead or carriage, depending on how much access you can get from the top and output area. Since the missing space is already open on your printers, you may be able to position the assembly and test-fit it before committing to a major teardown. However, if the mounting points are blocked by the carriage rail, upper frame, scanner section, or paper-output structure, then more disassembly may be required.

I would not remove the printhead unless it becomes absolutely necessary. On the ET-8550, removing the printhead or carriage area can turn a moderate repair into a much larger job. It increases the risk of ink-line disturbance, air entering the ink system, FFC cable damage, printhead alignment issues, sensor problems, and reassembly complications. Since your printers are already printing well, it is wise to avoid disturbing the printhead assembly unless access truly requires it.

Before installing the star wheel assembly, inspect the empty mounting area carefully. Look for the screw posts, alignment slots, spring anchor points, and any metal contact points where grounding springs would normally touch. Compare the area against your ET-8500 if the design is similar enough to help visually identify how the assembly should sit. Take photos before and during the process so you have a reference if something shifts or does not line up.

When installing a star wheel assembly, the alignment is important. The wheels must sit evenly across the paper path. If one side is higher, lower, tilted, or not spring-loaded correctly, the paper may still exit poorly. A misaligned star wheel can also leave marks on glossy paper, drag the paper unevenly, or interfere with the print surface before the ink has dried. If grounding springs or tension springs are missing, the assembly may not press or float the way Epson intended.

Since your current workaround is printing on oversized paper and trimming the bottom, that confirms the printers are otherwise usable. Installing the star wheel assembly may improve the end-of-page control, but I would still keep in mind that the PE sensor or paper-feed timing could also be involved. The PE sensor tells the printer where the paper is during feeding and exiting. If the PE sensor is dirty, misaligned, slow to trigger, or mechanically obstructed, the printer can still misjudge the trailing edge of the page even after the star wheel assembly is installed. However, in your case, the fact that both machines are missing the same output-control assembly makes the star wheel assembly the first thing I would investigate.

You mentioned that one of the printers previously had main board power transistor issues and a blown Fuse 1. That type of repair usually relates more to printhead power or board-level protection than to the paper-exit assembly. Since that printer now prints well, the remaining bottom-of-page problem is more likely mechanical or sensor-related than related to the original blown fuse and transistor repair. The second printer having a similar paper-exit issue makes the missing star wheel assembly even more suspicious.

For the part purchase, please use the ET-8550 exploded diagram page and click directly on the star wheel assembly: ET-8550 Exploded Parts Diagram and Repair Reference Guide [https://bchtechnologies.com/products/et-8550-et8550-exploded-parts-diagram-repair-reference-guide-annotated-edition?_pos=1&_sid=1a9d5e5cc&_ss=r]. For the screws and springs, unfortunately, we cannot promise those are included unless they are shown or described in the product listing. If you need those exact hardware pieces, you may need to source them from a donor ET-8550, a hardware salvage unit, or another compatible Epson output assembly.

Addressing printer issues can be complicated because many problems require hands-on inspection, especially when small mechanical parts, springs, grounding contacts, sensors, and paper-path assemblies are involved. For that reason, we are not able to provide remote troubleshooting, suggestions, or support for individual printer repairs. We do offer in-person evaluation and repair through our local diagnostic facility: BCH Technologies Printer Repair Service [https://bchtechnologies.com/printer-repair-service]. Because of high demand, repairs are handled on a first-come, first-served basis, so it may take a few weeks before we can accept a printer for drop-off. Our services are structured to repair either a whole printer or specific printer parts, with instructions on how to proceed. However, we understand that our rates may not be the most economical option for every situation. For that reason, we strongly recommend self-help through online research whenever possible. You can start by checking YouTube or visiting our channel homepage: BCH Technologies on YouTube [https://youtube.com/@bchtechnologies]. Use the search icon next to "About" on the right-hand side of the menu bar to search for your specific model, part name, or symptom. We receive many questions every day asking for videos on specific topics, and after creating videos for many years, it is difficult to remember every single one by title. YouTube's search function is usually the fastest way to find the most relevant video, and it may also recommend helpful videos from other repair channels.

Thank you again for your detailed message and for your continued support. I am glad our previous help got both ET-8550 printers printing again, and I appreciate your thoughtful observations comparing the ET-8550 with the ET-8500. Hopefully, adding the missing star wheel assemblies will help resolve the paper-exit issue and allow you to use standard-size paper without trimming the bottom of each print.