Outboard Oil Drain Plugs & Gaskets

The drain plug washer is the most commonly skipped part of a DIY outboard oil change: and the cause of one of the most common post-service problems: an oil leak from the drain plug. A copper or aluminum crush washer is designed for single use only. Reusing a deformed washer from a previous service is a known cause of slow leaks that can deposit oil in the bilge, on the transom, and in the water.

Boat Max Online stocks OEM drain plug washers and lower unit bolt gaskets for Honda BF, Suzuki DF, and Yamaha F series outboards. These are inexpensive parts that should be replaced at every oil change: their cost is negligible compared to the cleanup and potential damage caused by an oil leak. We include drain plug gaskets in all of our complete oil change kits, and sell them individually for customers who service their engines with bulk oil purchases.

Lower unit bolt gaskets: used to seal the upper and lower gear oil drain plugs on the lower unit: are equally important. These should also be replaced at every gear lube service to ensure a watertight seal.

Common OEM Drain Plug Part Numbers