804142T Mercury Gear | Genuine Used Part

🔧 Product Description

Genuine Mercury 75HP-115HP Four-Stroke Oil Pump Driven Gear - Part Number: 43-804142T

A genuine Mercury driven gear used in the oil-pump assembly of selected Yamaha-manufactured Mercury four-stroke outboards.

Mercury catalogues identify the service number as 43-804142T. The gear works with drive gear 43-804151T01 to operate the engine lubrication pump.

⚙️ Key Features

• Genuine Mercury oil-pump driven gear
• Correct part number 43-804142T / 804142T
• Used on Yamaha-built Mercury inline-four engines
• Factory gear profile and bore
• Works with drive gear 43-804151T01
• Discontinued or limited-supply OEM component

🚤 Compatibility

Documented on selected

• Mercury 75HP carburetted four-stroke - serial 0G960500-1B226999
• Mercury 75HP EFI four-stroke - serial 1B172291-1B366822
• Mercury 80HP EFI four-stroke - serial 1B227000-1B366822
• Mercury 90HP carburetted four-stroke - serial 0G960500-1B226999
• Mercury 90HP EFI four-stroke - serial 1B172291-1B366822
• Mercury 100HP EFI four-stroke - serial 1B227000-1B366822
• Mercury 115HP EFI four-stroke - serial 0T178500-1B366822
• Specifically documented on 115 EFI serial groups 0T178500-0T800999 and 1B227000-1B366822
• Engine Type: Yamaha-manufactured Mercury inline-four four-stroke outboard
• HP Range: 75HP-115HP
• Fitment Requirement: Confirm the oil-pump diagram and engine serial number

🔌 Function

The gear transfers mechanical rotation to the engine oil pump so pressurised lubricant circulates through the crankshaft, camshaft and bearing galleries.

⚠️ Common Signs of Failure

• Oil pressure is low
• Gear teeth are damaged
• Oil pump does not rotate
• Abnormal gear noise occurs
• Debris appears in the engine oil
• Gear has excessive shaft clearance

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 43-804142T current documented driven-gear reference
• No direct supersession confirmed

OEM / Related Numbers

• 43-804142T
• 804142T
• 43-804151T01 related drive gear
• Related oil-pump assembly, shaft and retaining hardware
• Related Yamaha-manufactured powerhead components

Aftermarket / Verified Equivalents

• Specialist used or new-old-stock 804142T gear
• Used complete Mercury 75HP-115HP oil-pump assembly
• A Yamaha platform equivalent may exist, but no verified direct Yamaha service number was confirmed
• No verified direct aftermarket gear

📦 Condition

• Genuine used part
• Removed from running engine where applicable
• In good working condition unless otherwise stated
• Inspect gear teeth and mating drive gear before installation