865380a25 Mercruiser trim pump assembly | Genuine Used Part

🔧 Product Description

Genuine MerCruiser Oildyne Power Trim Pump Assembly - Part Number: 865380A25

A genuine MerCruiser 12-volt Oildyne hydraulic trim-pump assembly for selected Alpha and Bravo sterndrive systems. The assembly contains the electric motor, hydraulic pump, oil reservoir, control solenoids and quick-disconnect hydraulic fittings.

Part number 865380A25 is the later low-pressure, high-flow pump configuration with a three-pin inline electrical connector.

⚙️ Key Features

• Genuine MerCruiser OEM Oildyne trim-pump assembly
• Correct service number 865380A25
• Low-pressure, high-flow hydraulic configuration
• Quick-disconnect hydraulic hose fittings
• Used on selected Alpha One Gen II and Bravo transom systems

🚤 Compatibility

Commonly used on

• MerCruiser stern-drive hydraulic trim systems
• Late quick-connect Alpha and Bravo transom assemblies

Typically suits

• Drive models:
• MerCruiser Alpha One Gen II
• MerCruiser Bravo One
• MerCruiser Bravo Two
• MerCruiser Bravo Three
• MerCruiser Bravo X One
• MerCruiser Bravo X Two
• MerCruiser Bravo X Three
• MerCruiser Bravo XR One
• MerCruiser Bravo XR Three
• Later MerCruiser transom assemblies using quick-disconnect hydraulic lines and the three-pin pump connector
• Selected earlier Alpha One and Bravo installations when converted with adapter harness 865771A02 and two 808727 hydraulic fittings
• Drive Type: MerCruiser Alpha One Gen II and Bravo hydraulic trim systems
• Electrical System: 12-volt Oildyne pump with external UP and DOWN solenoids
• Year Range: Commonly 2000 onward for direct quick-connect installations; earlier systems may require conversion components

🔌 Function

The pump supplies hydraulic pressure to the sterndrive trim cylinders. Electrical solenoids reverse pump operation so the drive can be raised, lowered and held at the selected running-trim or trailer position.

⚠️ Common Signs of Failure

• Pump runs but the drive does not move
• Drive settles after being trimmed
• Trim operates in one direction only
• Hydraulic fluid leaks from the reservoir, fittings or pump body
• Solenoid clicks without pump operation
• Pump motor is slow, noisy or overheats
• Milky or contaminated hydraulic fluid
• Cracked reservoir or damaged quick-connect fittings

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 865380A25 later MerCruiser Oildyne trim-pump assembly
• 865380A25 → Replaces applicable 865380A15 and 865380A05 pump configurations
• 865380A15 → Related to 14336A22
• 14336A22 → Supersedes 14336A17
• 14336A17 → Supersedes 14336A15
• 14336A15 → Supersedes 14336A9
• 14336A9 → Supersedes 14336A6
• 14336A6 earlier MerCruiser trim-pump assembly
• 88183A12 and 96477A3 earlier related pump assemblies

OEM / Related Numbers

• 865380A25
• 865380A15
• 865380A05
• 865380A02
• 14336A28
• 14336A22
• 14336A17
• 14336A15
• 14336A9
• 14336A6
• 88183A12
• 88183A11
• 88183A6
• 96477A3
• 865380A13 related pump motor and reservoir assembly
• 865771A02 retrofit adapter harness
• 808727 retrofit hydraulic fittings

Aftermarket / Verified Equivalents

• Sierra: 18-6747
• ARCO Marine: 6285
• ARCO Marine: 6275
• Sterndrive Engineering: 9C-108SS
• Sterndrive Engineering: 9C-108
• Mallory: 9-18500
• Recmar / Marine Petrol Parts: 865380A25 replacement trim pump

📦 Condition

• Genuine used part
• Removed from running engine where applicable
• In good working condition unless otherwise stated