18525A1 Aftermarket Mercruiser One-Bolt Trim Reservoir | Sawley's Select Marine Parts

🔧 Product Description

Aftermarket replacement One-Bolt Power Trim Pump Reservoir - Replaces Part Number: 18525A1

New aftermarket plastic trim-pump reservoir replacing MerCruiser 18525A1. It uses a single bottom mounting bolt and right-side filler neck and also cross-references Volvo Penta 854531.

⚙️ Key Features

• Single-bolt bottom-mount reservoir

• Approximately 97mm reservoir diameter

• Right-side filler neck

• Direct fit to the applicable Oildyne-style trim pump

• Cross-brand MerCruiser and Volvo Penta application

🧰 Kit / Assembly Contents

• 1 × Plastic trim-pump reservoir - P/N 18525A1

• 1 × Reservoir-to-pump seal - supplied according to manufacturer package

• Filler plug/cap and mounting bolt - transferred or supplied according to package

🔄 Supersession & Cross Reference

OEM Supersession Chain:

• 18525A1 → Supersedes/cross-references 18525 and 17646

OEM / Related Numbers:

• 18525

• 17646

• Volvo Penta 854531

Aftermarket / Verified Equivalents:

• Sierra: 18-6771

• ARCO: M525

• Mallory: 9-18611

• MES: RSV01

• Recmar: REC18525A1 / PH200-T064-1B

🚤 Compatibility

Commonly used on:

• MerCruiser and Volvo Penta trim pumps using the one-bolt 97mm reservoir

Typically suits:

• Engine / Drive models:

• MerCruiser sterndrive trim-pump installations using 17646/18525/18525A1

• Volvo Penta applications using reservoir 854531

• HP / Drive Range: Drive rating dependent

• System Type: Electric-hydraulic sterndrive trim-pump reservoir

• Year Range: Model- and pump-style dependent

• Serial / Component Identification: Confirm one mounting bolt, 97mm diameter and right-side filler; four-bolt reservoirs are different.

🔌 Function

The reservoir stores hydraulic trim fluid and supplies the trim pump during cylinder extension and retraction while allowing displaced fluid to return.

Common signs of failure / service requirement:

• Hydraulic fluid leakage around the reservoir seam or mounting bolt

• Cracked, cloudy or distorted plastic reservoir

• Low trim-fluid level caused by a leaking tank

• Air entering the pump and causing erratic trim movement

• Damaged filler neck, cap seat or bottom seal

📦 Condition

• New aftermarket replacement part

• Brand new

• Supplied in original or equivalent packaging