Sierra 18-7909 4-Cycle Outboard Oil Filter – Honda BF75–BF250 4-Stroke

Sierra 18-7909 4-Cycle Outboard Oil Filter – Honda BF75–BF250 4-Stroke

Part Number: 18-7909  |  SKU: 47-7909  |  UPC: 808282265779

The Sierra 18-7909 is a marine spin-on oil filter for selected Honda BF-series 4-stroke outboard engines in the 75–250 HP range. It uses a 20 mm x 1.5 thread, heavy-wall steel canister with epoxy corrosion protection, high-efficiency filter media, and an anti-drain-back valve that helps retain oil pressure between uses and reduce dry-start conditions on startup.

Key Specifications

• Thread: 20 mm x 1.5
• Filter type: 4-cycle outboard spin-on oil filter
• Anti-drain-back valve: Yes
• Canister: Heavy-wall epoxy-coated steel
• Filter media: High-efficiency, meets or exceeds OEM specification
• Marine-duty construction for freshwater and saltwater environments

Compatible Applications

• Honda BF75 4-stroke outboards (selected model years — verify by OEM filter number)
• Honda BF90 4-stroke outboards (selected model years — verify by OEM filter number)
• Honda BF115 4-stroke outboards (selected model years — verify by OEM filter number)
• Honda BF130 4-stroke outboards (selected model years — verify by OEM filter number)
• Honda BF135 4-stroke outboards (selected model years — verify by OEM filter number)
• Honda BF150 4-stroke outboards (selected model years — verify by OEM filter number)
• Honda BF175 4-stroke outboards (selected model years — verify by OEM filter number)
• Honda BF200 4-stroke outboards (selected model years — verify by OEM filter number)
• Honda BF225 4-stroke outboards (selected model years — verify by OEM filter number)
• Honda BF250 4-stroke outboards (selected model years — verify by OEM filter number)

Fitment Note: Honda BF-series outboards use multiple oil filter references across different model years and configurations. Always confirm by engine model, model year, and existing OEM filter number before ordering. The strongest identifiers are part numbers in the Honda 15400-PLM, 15400-P0H, and 15400-ZJ1 families. The 20 mm x 1.5 thread is a useful secondary check.

Service Interval

Replace at every scheduled engine oil service. Follow Honda’s recommended maintenance schedule for your specific BF-series outboard — typically every 100 hours or once per season, whichever comes first. Refer to your Honda owner’s or service manual for your specific model.

Installation Notes

• Remove the old filter and confirm the old gasket has come away with it — a retained gasket will cause an oil leak
• Clean the filter mounting surface
• Lightly coat the new filter gasket with fresh engine oil before threading it on
• Tighten by hand plus ¾ turn, or per Honda service specification — do not over-tighten
• Run the engine and inspect for leaks before returning to service

OEM & Cross-Reference Part Numbers

• Sierra: 18-7909
• Honda: 15400-P0H-305, 15400-P0H-305PE, 15400-PLM-A01PE, 15400-PLM-A02, 15400-PLM-A02PE, 15400-ZJ1-004, 15410-ZJ4-999AH
• Mallory: 9-57810
• EMP: 35-57810

Related Products

• Sierra 18-7913 4-Cycle Outboard Oil Filter – Mercury & Honda — Sierra filter for Honda and Mercury 4-stroke applications using a different OEM reference
• Seachoice 50-21003 Full-Flow Oil Filter – Honda, Yamaha & Nissan/Tohatsu — value alternative for Honda 4-stroke outboards
• Sierra 18-7902 4-Cycle Outboard Oil Filter – Yamaha F15–F100 4-Stroke
• Sierra 18-7906-2 4-Cycle Outboard Oil Filter – Yamaha F150–F250 V6 & Mercury/Mariner F225

Parts Desk Insights

Best Use Case: Routine oil and filter changes on Honda BF75 through BF250 4-stroke outboards — Honda’s mid-to-large outboard lineup and one of the most respected 4-stroke outboard families on the market. Honda BF-series outboards are known for reliability and long service intervals, but they do require regular oil and filter maintenance. This filter covers a broad span of the Honda 4-stroke lineup, making it a useful stock item for shops servicing Honda outboards.

Common Issues: Honda uses multiple oil filter part numbers across the BF-series lineup, and several look similar in size and thread. The most reliable fitment check is matching one of the Honda 15400-PLM / 15400-P0H / 15400-ZJ1 numbers against the filter currently on the engine. If a customer can’t find a number on the old filter, the engine model year and horsepower will help narrow it down. As with all spin-on filters, remind customers to confirm the old gasket comes off with the old filter before installing the new one.