16700-ZZ5-003 Mechanical Fuel Pump Assembly

Mechanical Fuel Pump — Compatible with select Honda BF40D / BF50D Four-Stroke

Which pump is this?

This is Honda 16700-ZZ5-003, the mechanical fuel-pump assembly for D-generation BF40D and BF50D four-stroke outboards. Compatible with the two rows in the table: BF40D from VIN BBDJ-1000001 up, BF50D from BBEJ-1000001 up (about 2007 onward, including DK2 / DK4 VIN notes in the workbook). It is not the A-generation cylinder-head pump 16700-ZV5-003 / 16700-ZW1-004 used on BF25A–BF90A (21FP011). A 40 HP Honda badge is not enough — BF40A and BF40D take different pumps. Cross-ref 18-35304 on some internal tables belongs to a small Suzuki / Yamaha pump family, not this Honda D-gen pump.

Signs yours is due

• BF40D / BF50D four-stroke cranks long when hot, then runs once primed — D-gen mechanical pump diaphragm tired.
• Fuel smell at the cylinder-head pump on a D-series cowling (look for BF40D / BF50D, not BF40A).
• VIN starts BBDJ or BBEJ 1000001 up and the old stamp is 16700-ZZ5-003.
• Not an electric feed pump 16735-ZY3 on larger EFI Honda, and not BF60 16700-ZZ3.

Will it fit?

Compatible with Honda BF40D and BF50D only, as in the table. VIN-style starts: BBDJ-1000001 up for BF40D, BBEJ-1000001 up for BF50D. DK2 / DK4 bands are noted in the workbook. BF40A / BF50A / BF25A–90A use 16700-ZV5 / ZW1 (21FP011). BF8–20 use 16700-ZW9. BF60 uses 16700-ZZ3. Do not order this SKU for those.

Engine horsepower alone does not prove fit. Match the number stamped on the pump you remove to the OEM column.

Every row is from this SKU fitment workbook (2 rows after empty-line filter). Same horsepower name shipped different pumps.

OEM and swap numbers

OEM / predecessor numbers keep the engine-brand column. Aftermarket cross-refs are numbers only.

Wrong part

• NOT 16700-ZV5-003 / 16700-ZW1-004 — A-generation BF25–90 (21FP011).
• NOT 18-35304 — that number is a small Suzuki / Yamaha pump family, not Honda D-gen.
• NOT 16700-ZW9 (BF8–20), 16700-ZZ3 (BF60), or 16700-ZY9 (BF75D / 90D).
• NOT electric feed pump 16735-ZY3. NOT a fuel-filter cartridge.

What ships

One complete mechanical fuel-pump assembly 16700-ZZ5-003. No filter, no extra hose.

Often replaced together

A-generation BF25–90 pump is 21FP011. BF8–20 Honda pump is 16700-ZW9-003 (different family, not this page).

Install

Read BF40D vs BF40A on the cowl and the VIN on the transom bracket. Photograph the head-mounted pump hoses. Replace the gasket, align any pulse / fuel ports, and snug evenly — these small Honda pumps warp if over-torqued. Prime, leak-check, idle on muffs. If the old stamp is 16700-ZV5, you want 21FP011, not this page.

Frequently Asked Questions

Will this fit my Honda 40 HP?

Only BF40D (D-generation, VIN BBDJ-1000001 up). BF40A uses 16700-ZV5 (21FP011).

Is 18-35304 the same?

No. That number is a different small-engine family. This page is Honda 16700-ZZ5-003 only.

BF50A?

No. BF50D only. A-generation is 21FP011.

Old title said fuel filter.

Template error. Mechanical fuel pump.

What ships?

One 16700-ZZ5-003 pump. Not a filter, not the A-generation ZV5 pump.

Please note

Aftermarket fuel pump by GHMarine. Not affiliated with the engine brands named above. «Compatible with», «Replaces», and cross-ref numbers mean this part is built to work like the originals listed — always confirm the stamp on the removed pump, the engine model, and the serial range before you order. This page is the pump only, not a multi-part kit.