Lower Unit Gear Lube Oil Pump – Fits Mercury Outboard, Yamaha, Honda & MerCruiser Sterndrives (Replaces 26-830749, 8M0204693)

Lower Unit Gear Lube Oil Pump – Fits Mercury, Yamaha, Honda & MerCruiser

This lower unit gear lube oil pump is designed for changing gearcase oil in a wide range of marine engines. It is compatible with many Mercury outboards and MerCruiser sterndrives, as well as most outboard motors from Yamaha, Honda, and Suzuki. This pump fits standard quart plastic bottles with a 28mm opening.

It serves as a direct replacement for Mercury OEM part numbers 26-830749, 8M0204693, 830749, and 8M0204693.

• Installation Method: Manual hand pump for easy, controlled oil changes.
• Versatile Fittings: Includes 3/8" swivel, 8mm, and 10mm metal adapters to fit various lower unit drain plugs.
• Efficient Operation: Delivers approximately 8cc of fluid per pump stroke for quick and clean fluid transfer.

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket brands.

Compatible Engine Models

Confirm your engine model/year in the table below. For Mercury owners, here’s a guide to help you identify your engine’s serial/model: Mercury Serial Number Guide. You can also review exploded diagrams to verify part numbers: Mercury Parts Diagrams & Catalog.

Confirm your engine model/year in the table below. For Yamaha owners, here’s a guide to help you identify your engine’s serial/model: Yamaha Serial Number Guide. You can also review exploded diagrams to verify part numbers: Yamaha Parts Diagrams & Catalog.

Confirm your engine model/year in the table below. For Suzuki owners, You can review exploded diagrams here to verify part numbers: Suzuki Parts Diagrams & Catalog.

Note: This pump is broadly compatible with most Yamaha, Honda, and Suzuki outboard motors. However, it is NOT compatible with Volvo Penta models.

Technical Specifications

Package Contents

• 1 x Lower Unit Gear Lube Oil Pump Assembly
• 1 x 3/8" Swivel Adapter
• 1 x 8mm Metal Adapter
• 1 x 10mm Metal Adapter
• 2 x Rigid Suction Tubes (13cm, 15cm)
• 1 x Cap Adapter (for 28mm bottle opening)
• 1 x Flexible Clear Fill Tube
• 2 x Drain Gasket (for Mercury/Mercruiser models 830749)

Installation Guide

1. Position a drain pan under the lower unit of your outboard or sterndrive.
2. Remove the lower (drain) and upper (vent) screws from the gearcase. Allow all old oil to drain completely.
3. Select the appropriate adapter (3/8", 8mm, or 10mm) and attach it to the flexible clear fill tube.
4. Screw the pump onto a standard quart bottle of new lower unit gear lube.
5. Insert the fill tube adapter into the lower drain hole and turn clockwise to secure it.
6. Pump the new gear lube into the gearcase. Continue until you see fresh lube emerge from the upper vent hole.
7. Re-install the upper vent screw while keeping the fill tube in the lower hole to prevent spills.
8. Quickly remove the fill tube and re-install the lower drain screw.
9. Tighten both screws to the manufacturer's specified torque. Do not overtighten.
10. Wipe the lower unit clean and check for leaks.

Troubleshooting & FAQ

Q: How do I know if this pump will fit my engine's lower unit?

A: This pump is designed to be versatile. It includes a 3/8" adapter for most Mercury/MerCruiser models and 8mm/10mm adapters for many Yamaha, Honda, Suzuki, and other Japanese outboards. Cross-reference your OEM part number with 26-830749 or 8M0204693. Please note it does not fit Volvo Penta models.

Q: The pump isn't drawing oil from the bottle. What's wrong?

A: First, ensure the pump is screwed tightly onto the 28mm opening of the gear lube bottle to create a proper seal. Second, check that the suction tube is fully submerged in the oil. If the bottle is low, the pump may draw air. Finally, confirm the pump mechanism is clean and free of debris.

Q: How is this different from the original Mercury or Yamaha pump?

A: As an aftermarket part, this pump is designed to meet or exceed OEM specifications for fit and function at a more competitive price. It is constructed from durable plastic with metal adapters, similar to many OEM versions, and provides a reliable solution for DIY oil changes.

Q: OEM vs. Aftermarket?

A: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

Q: How fast do you ship and how much does it cost?

A: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

Q: What is your warranty and return policy?

A: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

• Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.