3H8-04000-1 Mechanical Fuel Pump Assembly

Mechanical Fuel Pump — Compatible with select Tohatsu Nissan Mercury and Johnson Evinrude 9.9–30 HP Four-Stroke

Which pump is this?

This is one mechanical four-stroke fuel pump sold under three OEM stamps. Tohatsu / Nissan 3H8-04000-1 covers MFS/NSF 9.9–30 four-stroke catalog codes in the table (B/C/E generations as listed). Mercury / Mariner 803529T04 covers JPN-platform 9.9–30 HP four-stroke serial bands (carb and 333cc EFI, including SeaPro / ProKicker / 25–30 EFI 3-cyl rows). Johnson / Evinrude 5041064 covers 15 HP four-stroke B15 / E15 model codes only — 52 of the 80 rows. It is not Tohatsu 3H6-04000 (17FP001, 4–9.8 HP). It is not Mercury 803529T06 (4–6 HP) or T07 (8/9.9 209cc). It is not the 2-stroke 9.9/15 HP pump 438562 (24FP096).

Signs yours is due

• MFS9.9–30 or Mercury JPN 9.9–30 four-stroke cranks, fires, then dies — mechanical lift pump tired.
• Fuel weep at the block pump on a four-stroke 15 HP Johnson/Evinrude B15/E15 code, not a 2-stroke 15.
• Stamp is 3H8-04000-1, 803529T04, or 5041064 — not 3H6-04000 and not 438562.
• Not a cooling impeller, and not a 2-stroke VRO.

Will it fit?

Compatible with three blocks in the 80-row table. Tohatsu/Nissan: MFS9.9B/C/E, MFS15B/C, MFS18B, MFS20C, MFS25A/B/C, MFS30B, NSF25A/30A and NSF B 9.9/15/18, years as printed. Mercury: 9.9 EFI ProKicker 1R008146–1R278792; 10 carb 0R575531–0R833819 and 10 EFI 0R833820 & up; 15/20 carb and EFI bands through 0R833819 then 0R833820 & up; 25/30 EFI 3-cyl 0R106999–1R162636 and 1R154758 & up. Johnson/Evinrude: 15 HP four-stroke model codes B15* / E15* on 5041064. Horsepower 15 alone is not enough — 2-stroke 15 HP is 24FP096.

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 (80 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 3H6-04000-1 — 4–9.8 HP Tohatsu family (17FP001).
• NOT 803529T06 / T07 — 4–6 HP and 8/9.9 209cc Mercury segments, not this 333cc T04 table.
• NOT 438562 / 0438562 — 2-stroke 9.9/15 (24FP096).
• NOT kits 26FFK035 / 26FFK036 (pump plus filter) as this SKU.

What ships

One complete mechanical fuel-pump assembly. Stamp may read 3H8-04000-1, 803529T04, or 5041064. No filter.

Often replaced together

Tohatsu 3H6 4–9.8 HP is 17FP001. 2-stroke 9.9/15 is 24FP096. Pump-plus-filter kits 26FFK035 / 26FFK036 are not this single pump.

Install

Identify the platform first: Tohatsu MFS/NSF code, Mercury JPN serial, or Johnson/Evinrude 15 HP four-stroke model code. Photograph the pulse hose. Clean the pad, align the pulse hole, snug evenly. Prime, leak-check, idle on muffs. If the motor is 2-stroke 9.9/15, you want 24FP096. If the Tohatsu stamp is 3H6, you want 17FP001.

Frequently Asked Questions

Will this fit my 15 HP Johnson?

Only four-stroke 15 HP B15/E15 codes in the table (5041064). 2-stroke 15 HP 1993–2007 is 24FP096 (438562).

Mercury 15 HP four-stroke?

Yes if the serial is in the 803529T04 bands (carb or 333cc EFI). Read the serial, not just 15 HP.

Is 3H8 the same as 3H6?

No. One digit off is a different small Tohatsu family (17FP001).

What ships?

One pump. Not 26FFK035 / 26FFK036.

Tohatsu 25 / 30?

MFS25 / MFS30 four-stroke rows in the table are included. Match the catalog code.

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.