Mercury Gear Lube pump with adaptors

Mercury / MerCruiser Gear Lube Pump (Part 91‑8M0072135) — OEM Marine Accessory

Product Overview
The Mercury Marine OEM Gear Lube Pump, Part 91‑8M0072135, is a factory-original tool designed for mess-free filling of lower unit or sterndrive gearcases. It fits standard 32 oz (946 ml) gear lube bottles and inserts into any outboard or stern drive with a 3/8″‑16 drain/fill plug, providing a secure threaded connection for safe, clean lubrication.

Key Features & Compatibility

• Genuine Mercury Marine OEM part, not aftermarket
• Includes a metric M8×1.25 adapter for gearcases with metric drain plugs (some Japanese models)
• Compatible with all quart (32 oz) and 946mL gear lube bottles
• Suitable for MerCruiser sterndrives, Mercury and Mariner outboards, Speedmaster gear housings, as well as many models from Yamaha, Suzuki, Honda, Volvo Penta, Cobra, and OMC

Benefits for Boaters & Technicians

• Cleaner oil changes by pumping directly from bottle to gearcase, minimizing spillage and contamination
• Fast, secure fit via threaded fitting reduces risk of leaks during fluid changes
• Universal fit adaptability with included adapter makes it versatile across multiple engine types

Specifications

1. Remove gearcase drain/fill plug (3/8″‑16 or metric).
2. Thread the pump’s hose fitting securely into the gearcase.
3. Use the included adapter if needed for M8×1.25 plug types.
4. Pump gear lube straight from the bottle until filled.
5. Remove the pump and reinstall the drain plug.

Search Keywords

• Mercury Gear Lube Pump 91‑8M0072135
• MerCruiser lower unit oil pump
• Outboard gear oil pump quart bottle
• Marine gearcase lube pump
• OEM lower unit gear oil filler

Why It Matters
For marine technicians and DIY boat owners alike, the 91‑8M0072135 Gear Lube Pump simplifies the gear lube change process. Its clean operation and secure fit help extend the life of your marine engine’s lower unit by ensuring complete and contamination-free lubrication.