8M0141844 Mechanical Fuel Pump Assembly

Mechanical Fuel Pump — Compatible with select Mercury Mariner 25 / 30 / 40 HP Four-Stroke Carb

Which pump is this?

This is one complete mechanical diaphragm fuel-pump assembly for Mercury / Mariner four-stroke carbureted 3-cylinder 25 / 30 / 40 HP engines. Current ordering number is 8M0141844. Predecessors on this carb family: 881862T1, 881862T07, 892874T, 899106T, 8M0118176. Compatible with the three carb rows in the table — 25 HP carb, 30 HP carb 3-cyl, 40 HP carb 3-cyl — in the serial bands listed (examples: 0P153500 through later 0T409000 / 1B / 1C ranges). It is not the EFI 30–60 HP family (881862T / T08, 892874T01, 899106T01, 8M0118177, 8M0141827). Aftermarket pages that merge carb and EFI under one number are too wide. Horsepower 50 / 60 EFI is not this pump.

Signs yours is due

• 25 / 30 / 40 HP four-stroke carb 3-cyl cranks, fires, then dies until you pump the bulb — carb float bowl is not being filled.
• Fuel weep at the mechanical pump on a carb motor (throttle body / carb still has bowls, not a VST-only EFI setup).
• You compared the old stamp: 881862T1 or 881862T07, not 881862T08 / 8M0141827.
• Not 2-stroke 30–65 HP 14360A16 / A78 (21FP012 family). Not a water-pump impeller.

Will it fit?

Compatible with Mercury / Mariner 25 HP carb, 30 HP carb 3-cylinder, and 40 HP carb 3-cylinder four-stroke engines in the serial ranges in the table. Catalogs organize these by serial, not by model year — read the serial on the midsection or swivel bracket. 25 HP carb examples: 0P153500–0P388282 and 0T409000–1B344298. 30 HP carb 3-cyl examples: 0P153500–0P400999 and 0T409000–1B226999. 40 HP carb 3-cyl has the longest list (0P153500–0P400999, 0P401000–1B344306, 0T409000–1B226999, 1B227000–1B344306, 1C000001–1C018825, 1C018826–1C739634 across overlapping catalog pages). 30–60 HP EFI four-stroke uses a different pump family. Do not use cowl horsepower alone: a 40 HP EFI and a 40 HP carb are not the same pump.

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 (3 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 8M0141827 / 881862T08 / 892874T01 / 899106T01 — EFI 30–60 HP family (21FP005).
• NOT 18-8866 — that cross-ref tracks the EFI family, not this carb pump.
• NOT 803529T06 / 803529T04 (small 4–6 / 8–9.9 HP four-stroke) and NOT 2-stroke 14360A16 / A78.
• NOT kit 26FFK030 (this pump plus a filter). This page is the pump only.

What ships

One complete mechanical fuel-pump assembly. No fuel filter, no EFI VST pump, no carburetor kit.

Often replaced together

EFI 30–60 HP four-stroke pumps are 21FP005, not this page. 26FFK030 is the pump-plus-filter kit. 2-stroke 30–65 HP pumps are 21FP012 (identity still unconfirmed on A16 vs A78 — do not mix).

Install

Confirm carb vs EFI before you open the cowl: this pump is for carb 3-cyl 25 / 30 / 40 HP four-stroke. Read the serial against the table. Photograph the pulse hose. Remove the flange screws, scrape the pad, fit a new gasket with the pulse hole open. Do not install an EFI-family body (8M0141827) on a carb pad or the other way around — brackets can look close. Snug screws evenly. Prime the bulb, leak-check, idle on muffs, then a short lake test. If the motor is 50 / 60 EFI, stop — wrong SKU.

Frequently Asked Questions

Will this fit my Mercury 40 HP four-stroke?

Only the carb 3-cylinder serial bands in the table. 40 HP EFI uses 8M0141827 / 881862T08 (21FP005). Read carb vs EFI and the serial.

Is 18-8866 the same?

No. 18-8866 tracks the EFI family. This carb page does not replace 18-8866.

Is 881862T07 the same as 881862T08?

No. T07 is on this carb family. T08 is EFI. One letter / suffix off is a different pump.

What serial do I need?

Examples in the table: 25 HP carb 0P153500–0P388282 and 0T409000–1B344298; 30 / 40 HP carb use the overlapping 0P / 0T / 1B / 1C bands listed. Match your serial to a row.

What ships?

One mechanical pump assembly. Not the 26FFK030 kit.

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.