The size varies by model and engine; there is no single universal Honda drain plug washer size. In practice, you’ll typically encounter a drain plug head around 14 mm or 17 mm, and the aluminum crush washer sealed to that plug is sized to fit that specific plug (roughly a 20–24 mm outer diameter). To be certain, check your vehicle’s manual or use OEM replacement parts for your exact model and year.
Below is a detailed guide to help you identify and verify the correct size for your Honda, with practical steps to ensure you replace the washer correctly at every oil change.
Understanding the drain plug and washer
The oil drain plug screws into the oil pan and is paired with a crush washer that seals the joint. Honda’s engine designs have evolved across models and years, so the exact plug head size and washer dimensions can vary between B-series, K-series, and newer engines, as well as between different Honda models.
Common drain plug head sizes
Before listing sizes, note that exact dimensions depend on the engine. The two sizes you are most likely to encounter are:
- 14 mm: The most common head size on many modern Honda engines; a 14 mm socket or wrench will typically remove/install the drain plug.
- 17 mm: Some older or specific Honda engines use a 17 mm head for the drain plug.
These values cover the majority of Honda gasoline engines in recent decades, though there are exceptions. Always verify for your exact model and year.
Crush washer size and replacement approach
The crush washer that seals the drain plug is made to fit the corresponding plug and oil pan design. Because washer size is model-specific, Honda parts catalogs usually list the exact crush washer (often sold as a drain plug washer kit) by part number rather than by a simple outer diameter. When replacing, it’s best to use the OEM washer that matches your plug, or bring the old washer to a parts store to ensure a precise match.
- Do not reuse a damaged or deformed crush washer; replace it at every oil change.
- OEM part numbers will ensure compatibility if you’re unsure of the fitment.
In most Honda engines, the drain plug’s thread is M14x1.5, and the corresponding crush washer is designed to seal that fit; however, actual sizes may vary by model and year. Always confirm with the service manual or dealer.
How to verify the exact size for your car
To ensure you get the correct washer and plug size, verify using these reliable methods:
- Check the owner’s manual or service manual for the oil drain plug specification and part numbers.
- Look up the exact parts diagram for your vehicle by model-year on Honda’s official parts site or a reputable parts retailer. The diagram will show the drain plug and crush washer part numbers.
- Measure the drain plug head with a caliper or ruler to determine whether it is 14 mm or 17 mm, which helps identify the correct socket size and washer type.
- Bring the old washer to a parts store to match a replacement, or use the OEM replacement kit that covers your model.
By confirming the model- and year-specific size, you’ll ensure a proper seal and avoid leaks or over-tightening.
Summary
Honda drain plug washer sizes vary by engine and model. The drain plug head is commonly 14 mm or 17 mm, and the aluminum crush washer is sized to fit that plug, with an outer diameter typically in the 20–24 mm range. Always verify for your specific vehicle using the manual, parts diagrams, or a dealership parts counter, and replace the washer with the correct OEM part at every oil change.
If you share your exact Honda model and year, I can provide the precise drain plug head size and the corresponding crush washer part number for that vehicle.
What size is the drain plug on a Honda?
Engine Oil Drain Plug, Oil Pan Drain Plug, Bolt Plug (14MM)
Description: Notes: Included with oil pan.
What size is the drain plug washer on a 2010 Honda Civic?
2010 Honda Civic Washer, Drain Plug (14MM)
What size is the drain plug washer on a 2016 Honda Accord?
2016 Honda Accord Washer, Drain Plug (14MM)
What size is the drain plug washer on a Honda?
14mm
Oil Drain Plug Washer 14mm.