The oil drain plug washer on a Honda Fit is a copper crush washer that fits the drain plug bolt used by your engine. In practice, the inner hole size matches the bolt (most Fits use either an M12 or an M14 bolt) and the outer diameter is typically about 19–22 mm. The exact size depends on the model year and engine, so verify for your car.
Understanding the drain plug washer
The drain plug washer seals between the oil pan and the drain plug. It is a crush washer, meaning it deforms to create a leak-tight seal when the plug is tightened. Different Fit generations may use different bolt sizes, which in turn determine the washer diameter you need.
Common bolt sizes used on Honda Fits
The Fit has used different drain plug bolt sizes across generations. The two most common bolt sizes are M12x1.5 and M14x1.5, each requiring a corresponding copper crush washer.
- For M12x1.5 drain plug bolts: inner diameter about 12 mm; outer diameter typically around 19–20 mm.
- For M14x1.5 drain plug bolts: inner diameter about 14 mm; outer diameter typically around 22 mm.
Because sizes can vary by year and engine, use the washer that matches the bolt size in your specific vehicle. If in doubt, bring the old washer to the parts counter or consult your service manual.
How to confirm the exact size for your car
Before buying a new washer, confirm the size to ensure a proper seal. The following steps help you identify the correct crush washer for your Honda Fit.
- Check the owner's manual or service manual for the oil drain plug specification and the required crush washer size.
- Inspect the drain plug bolt: the bolt head size can hint the thread size (M12 vs M14) and the corresponding washer size.
- If you can't confirm, measure the old washer's inner hole with calipers. The inner diameter should match the bolt's shank diameter (roughly 12 mm or 14 mm).
- Bring the old washer or bolt to an auto parts store to match the size, or buy a copper crush washer kit that covers both sizes.
Having the correct washer is important to avoid leaks; a too-small or too-large washer can fail to seal properly.
Where to buy
Washers are inexpensive and widely available. Choose OEM or reputable aftermarket copper crush washers designed for oil drain plugs. The Fit commonly uses the following:
- OEM Honda copper drain plug washers sized for M12 or M14 drain plugs. Check your model/year and order the right one.
- Aftermarket copper crush washers sold as "oil drain plug washers" in packs that include both sizes.
When ordering, ensure you select the washer with the correct inner hole size and a suitable outer diameter to seal against your oil pan.
Summary
In short, the Honda Fit oil drain plug washer is a copper crush washer sized to fit the drain plug bolt used on your engine (most Fits use either M12x1.5 or M14x1.5). Verify your model year and engine and use the OEM washer to ensure a proper seal. If in doubt, bring the old washer or bolt to the parts counter or consult the service manual.