Aftermarket Mercury 6HP, 8HP 15HP 2-Stroke Service Kit (USA Models) | Sawley's Select Marine Parts

🔧 Product Description

Aftermarket major service kit for selected USA-built Mercury and Mariner 6HP, 8HP and 15HP carburetted two-stroke outboards from the compact twin-cylinder family. These engines are commonly identified by USA serial prefixes and, on applicable models, the twist-and-pull choke arrangement and integral/remote fuel-system layout used by Mercury-built engines rather than the Japanese-built Tohatsu-derived 0N-prefix family.

Because the 6HP/8HP and 15HP versions use different spark-plug specifications in the Mercury service data, the plug pair must be selected to match the exact horsepower and serial number. The shared complete water-pump assembly is the Mercury 46-42089A5 family.

⚙️ Key Features

• Major service package for USA-built compact twin-cylinder two-stroke outboards

• Complete upper-and-lower water-pump repair package

• Includes horsepower-correct spark plugs, fuel filter and gearcase drain seals

• Separates USA-built Mercury engines from Japanese 0N-prefix models

• Extensively cross-referenced to Sierra, GLM and SEI pump kits

📋 Kit Contents

Kit contents:

• 1 × Complete water-pump repair kit - Mercury 46-42089A5

• 2 × Spark plugs selected to engine specification:

- Mercury 6HP and 8HP: NGK BP8H-N-10

- Mercury 15HP: NGK BP8HS-15

- NGK BPZ8H-N-10 may be used only where the service specification calls for an RFI-suppressed alternative

• 1 × Fuel filter - Mercury 35-80365M / related 35-16248 family where specified by the serialised parts catalogue

• 2 × Gearcase drain/fill screw sealing washers - Mercury 12-191833 family

Water-pump kit 46-42089A5 component breakdown:

• 1 × Impeller - Mercury 47-42038-2

• 1 × Wear plate - Mercury 42200

• 1 × Gasket - Mercury 27-19202

• 1 × Gasket - Mercury 27-19204-3

• 2 × Gaskets/washers - Mercury 12-19183

• 2 × Gaskets - Mercury 19643

• 1 × Pump base/lower housing - Mercury 46-42040T5

• 1 × Upper pump housing - Mercury 46-42089A2

• 1 × Retainer - Mercury 42375

• 2 × Oil seals - Mercury 26-41365-1

• 1 × Seal - Mercury 26-33613

• 1 × Seal - Mercury 26-42133

• 1 × Pump screw - Mercury 10-48408

• 1 × Quad ring - Mercury 25-822236

• 2 × Housing washers - commonly catalogued under Mercury 12-16448 in this pump family

• 1 × Drive key - Mercury 28-42376A2 where included by the selected current kit revision

Related service parts not included unless separately stated:

• Mercury 14586-series thermostat

• Mercury 27-43006-8 thermostat gasket

🔄 Supersession & Cross Reference

OEM / Related References:

• Mercury 46-42089A5 - Complete water-pump repair kit

• Earlier/alternate kit references: 46-42089A4, 46-42089A3, 46-42040A5 and 46-42040T5

• Mercury 47-42038-2 - Impeller

• Mercury 35-80365M / 35-16248 - Fuel-filter references, serial dependent

• Mercury 14586-series thermostat and 27-43006-8 gasket - Related cooling-system service parts, not included unless separately stated

Verified Aftermarket / Other-Brand Equivalents:

• Sierra 18-3149 - Complete water-pump repair kit equivalent

• GLM 12305 - Complete water-pump repair kit equivalent

• SEI 96-261-01K - Complete water-pump repair kit equivalent

🚤 Compatibility

Commonly used on selected USA-built:

• Mercury 6HP twin-cylinder two-stroke - commonly from serial A197112 through T800749, subject to model catalogue

• Mercury 8HP twin-cylinder two-stroke - commonly from serial A197112 and later within the applicable USA-built family

• Mercury 15HP twin-cylinder two-stroke - commonly from serial B292414 and later within the applicable USA-built family

• Corresponding Mariner Mercury-built versions

Identification Notes:

• USA serial-number family rather than Japanese 0N-prefix production

• Mercury-built compact twin-cylinder powerhead

• 46-42089A5 water-pump arrangement

• Spark plugs must be selected by horsepower: BP8H-N-10 for 6HP/8HP and BP8HS-15 for 15HP unless the engine decal/manual specifies otherwise

Important Exclusions:

• Not for Japanese-built 6HP, 8HP or 9.9HP models using Tohatsu 3B2-87322-series pump components

• Not for four-stroke engines

• Not for later 0R-prefix four-stroke/Tohatsu-derived platforms

• Not for 9.9HP unless the exact serialised Mercury catalogue confirms the same USA service configuration

🔌 Function

Renews the main ignition, fuel-filtration, gearcase sealing and complete water-pump components required for scheduled maintenance. Replacing the complete pump housings and seals is appropriate when the pump has been run dry, the housing is melted or scored, or oil seals have hardened.

Common signs service is due include:

• Hard starting, weak idle or plug fouling

• Restricted fuel flow

• Weak tell-tale discharge or overheating

• Melted/scored pump housing, damaged impeller or worn seals

• Gearcase-oil seepage at drain screws

📦 Condition

• Brand-new aftermarket service kit

• New, unused replacement parts

• Spark-plug specification is selected to suit the nominated horsepower and serial number

• Confirm USA-built engine identification and 46-42089A5 pump layout before fitting