The Honda 90503-YD4-003 Seal Washer is a genuine OEM component designed for the WT40 water pump. As a direct Honda replacement, this washer is manufactured to the same standards as the original part it replaces, making it the correct choice when servicing your WT40. Confirm your unit's serial number against the fitment table before ordering to ensure part number 90503-YD4-003 is the right match for your production run.
Key Features
- Genuine OEM Sealing Integrity — manufactured by Honda to deliver the same sealing performance as the original, maintaining a proper liquid-tight connection at the mating surface it was designed for.
- Direct WT40 Fitment — built specifically for the Honda WT40 water pump; no adaptation needed to install this replacement.
- Serial Number Verification Recommended — Honda updates parts at production breaks, so cross-check your pump's serial number against the fitment table to confirm this is the correct seal washer for your unit.
- Prevents Leaks at the Source — a worn or damaged seal washer can allow fluid to escape at threaded or mating joints, leading to pressure loss and pump inefficiency; replacing it promptly restores a clean, dry connection.
A seal washer is a precision sealing component used at threaded fittings and mating surfaces to prevent fluid from escaping under pressure. In the WT40 water pump, it provides a reliable, compressible seal that closes off any gap between a fastener or fitting and its seat. When a seal washer deteriorates or is damaged during service, the joint it seals can begin to weep or leak, reducing pump efficiency and potentially allowing water ingress into areas where it can cause further damage. Replacing it with the correct Honda part restores a clean, leak-free connection.
Part Details
| Part Number | 90503-YD4-003 |
|---|---|
| Brand | Honda |
| Part Type | Genuine OEM |
| Description | Seal Washer |
Compatibility & Fitment
| Name | Models | Serial Range |
|---|---|---|
| Water Pump | WT40 | All |
Verify Before You Order
Fitment is machine-number and revision-specific; always confirm your model and serial number against the fitment list.
Why Buy From DHS Equipment
Every part is verified against the manufacturer's part number before it ships, so what you order is what arrives. We carry parts from leading OEM brands and our own DHS Quality Parts line of professional aftermarket components. Need help finding the right part? Our team is available to confirm compatibility whenever you need it. Orders are processed fast to keep your jobs on track. We don't just sell parts. We keep you jobsite ready.
Questions? Contact our team at [email protected] or 866-611-9369 — DHS Equipment is here to help you maintain peak performance.
