Epson ET-8550 Replacement Printhead Missing Ink Gaskets or Washers: What Are They and Do You Need Them?

Question

I bought a replacement printhead for my Epson ET-8550 from Amazon after watching the Epson ET-8550 Printhead Replacement Complete Tutorial. The replacement printhead does not have the small ink-related pieces that sit at the ink inlet connections on the printhead. What are those pieces called? Are they supposed to come with a replacement printhead, and do I need them before installing the new head?

Answer

The small pieces you are referring to are generally called gaskets, washers, grommets, seals, or printhead inlet seals. You may see different sellers use slightly different terminology, but they perform essentially the same job: they create a seal between the ink supply connection and the ink inlet on the printhead.

On the Epson ET-8550, these seals are especially important because the printer has six ink channels. Each connection needs to seal correctly so that ink can reach the printhead without introducing excessive air into the ink path or allowing ink to leak around the connection.

A New Printhead May Not Include the Gaskets

It is not necessarily unusual for a replacement printhead to arrive without these seals. Some genuine service replacement printheads may be supplied primarily as the printhead itself, meaning certain small components from the original assembly need to be transferred to the replacement head.

At the same time, some refurbished or aftermarket printheads are sold as more complete assemblies and may already have seals or similar parts installed.

Therefore, I would not determine whether a printhead is genuine or counterfeit simply based on whether these washers are included. Marketplace printhead listings can vary considerably in what components are supplied and how the product is described.

If your replacement head does not have the washers, first examine your original ET-8550 printhead carefully. The original seals may still be attached to the old printhead or may remain around the ink inlet connections. If they are still soft, undamaged, and correctly shaped, they may be reusable.

Inspect the Original Washers Before Reusing Them

If you transfer the washers from the original printhead, inspect each one carefully.

The gasket should not be torn, split, severely compressed, hardened, distorted, or swollen. It should sit evenly around the ink inlet and create a consistent seal when the ink connection is installed.

A damaged or improperly seated gasket can potentially cause:

• Air entering the ink line

• Difficulty priming an ink channel

• Intermittent or completely missing colors

• Ink leaking around the printhead inlet

• Nozzle-check problems that return after cleaning

• A channel that repeatedly loses prime

These symptoms can sometimes look like a defective printhead even when the actual problem is simply an inadequate seal between the ink supply and the head.

Also, do not stack two gaskets together in an attempt to improve the seal unless a particular modification specifically calls for that arrangement. An incorrect gasket thickness can prevent the connection from seating at the proper depth and may create additional ink-flow problems.

OEM Replacement Gasket Option

If the original gasket is missing or damaged and you would like an OEM-style replacement, we have an OEM Black Washer / Grommet Adapter Seal for Epson printheads available here:

OEM Black Washer / Grommet Adapter Seal for Epson Printhead [https://bchtechnologies.com/products/oem-black-washer-grommet-adapter-seal-washer-gasket-for-epson-printhead-1-piece]

This is sold as an individual seal, so check how many of your original seals are missing or damaged before ordering.

Aftermarket ET-8550 Silicone Gasket Option

We also offer a third-party silicone replacement set designed for the ET-8550:

6 Thick Silicone Washer Gaskets, 2.5 mm, for Epson ET-8550 [https://bchtechnologies.com/products/6-thick-silicone-washer-gaskets-2-5-mm-for-epson-et-8550-oem-washer-replacement]

This option provides six replacement gaskets, corresponding to the six ink channels in the ET-8550.

Whether you use the original Epson seals, OEM replacements, or compatible aftermarket seals, the important point is that every ink connection must sit securely and seal correctly.

Check the Printhead Carefully Before Installing It

Since the replacement printhead came from a marketplace seller, I would also recommend inspecting it carefully before installation.

Look at the electrical contacts, nozzle plate, ink inlet ports, and surrounding plastic. Compare the new head directly with your original head. The physical layout and electrical connections should match.

Be particularly cautious if you see ink residue on a product advertised as brand new, damaged contacts, scratches around the nozzle plate, missing components, or obvious signs that the unit has previously been installed.

Terms such as "new," "original," "OEM," and "refurbished" are not always used consistently by third-party marketplace sellers, so the seller's description alone may not establish the actual history of the printhead.

If you are uncertain about the head, it is worth resolving that question before powering the printer with it installed. A printhead is an electrical component as well as an ink-delivery component, and a damaged or internally shorted head can potentially create additional problems elsewhere in the printer.

Make Sure the Missing Parts Really Are the Gaskets

There are several small components associated with the ET-8550 ink-delivery system, so make sure the missing pieces are actually the inlet gaskets.

If you mean the small black or silicone rings that seal the ink connections where they meet the printhead, those are the washers/gaskets/grommet seals discussed above.

If you are referring to a larger plastic ink connection, manifold, adapter, damper, or another piece that was attached to the old head, that is a different component. In that situation, compare the original and replacement assemblies carefully before proceeding.

Addressing printer issues can be complicated because many of these problems require hands-on inspection and testing. For that reason, we're not able to provide individualized remote troubleshooting, repair instructions, or ongoing repair support. We do offer in-person evaluation and repair through our local printer diagnostic and repair facility [https://bchtechnologies.com/printer-repair-service]. Because demand is high, the service operates on a first-come, first-served basis, and it may take a few weeks before an appointment or drop-off opportunity becomes available. Our services are structured so that we can work on either a complete printer or certain individual components, with instructions explaining how to proceed. We also recognize that professional repair is not always the most economical option, so we strongly encourage customers who are comfortable doing their own repairs to research the issue online. You can begin with YouTube or visit the homepage of our BCH Technologies YouTube channel [https://youtube.com/@bchtechnologies]. Use the search icon near the "About" section of the channel to search for your printer model, error code, or specific repair topic. I receive dozens of questions every day asking whether we have a video covering a particular subject. After creating repair videos for more than nine years, it is difficult to remember every video we've published, so the YouTube search function is usually the fastest way to locate the relevant material. YouTube may also recommend helpful videos from other creators covering the same problem.

Thank you again for contacting us and for supporting BCH Technologies and our YouTube channel. I hope this clears up what those small parts are and helps you determine what is needed before installing your ET-8550 replacement printhead.