PartsVu Gear Lube Pump for Standard Quart Bottles - 3/8-16 Drain-Plug Fitting + 8mm Adapter - PV1005051

Use this PartsVu gear lube pump to transfer lower-unit gear lube from a standard quart bottle into compatible marine gearcases. This lower unit gear oil pump uses a 3/8-16 drain-plug fitting and includes an 8 mm adapter for additional compatible applications. Confirm your engine or sterndrive drain-plug thread, required adapter, gear-lube specification, and manufacturer service procedure before use. Gear lube is sold separately.

A useful tool for DIY marine maintenance, this quart bottle pump makes it easier to transfer fresh gear oil into a compatible outboard or sterndrive lower unit without pouring directly into the gearcase. The pump cap adapter is designed for standard quart bottles with a 28 mm or 1.125-inch opening, and a rubber cap is included to help keep the pump clean between uses.

Gear Lube Pump Fitment & Compatibility

Compatible Outboard & Sterndrive Applications

The pump is designed to support a wide range of marine lower-unit and sterndrive applications when the drain-plug fitting or included adapter matches the specific gearcase. Applications may include engines and drives from:

• Yamaha
• Mercury / MerCruiser
• Suzuki
• Tohatsu
• Honda
• Johnson / Evinrude
• OMC
• Cobra

Many applications use a standard 3/8-inch-style connection, while others may require the included 8 mm adapter. Do not select the pump by manufacturer name alone. Check the exact lower-unit drain/fill fitting and service information for your engine or sterndrive before ordering.

How to Use a Lower Unit Gear Lube Pump

A gear lube transfer pump is commonly used after the old lower-unit lubricant has been drained according to the engine or drive manufacturer's service procedure. The pump connects the quart bottle to the compatible lower drain/fill opening so fresh lubricant can be pumped into the gearcase.

1. Confirm the correct lower-unit gear lube and service procedure for the engine or drive.
2. Verify whether the lower-unit connection uses the pump's 3/8-16 fitting or requires the included 8 mm adapter.
3. Attach the pump securely to the compatible quart bottle and gearcase connection.
4. Fill the lower unit according to the manufacturer's instructions for drain/vent-plug order, fill level, and service procedure.
5. Install new drain or vent gaskets where specified and tighten the plugs to the manufacturer's required torque.
6. Clean the pump after use and install the included rubber cap before storage.

Lower-unit procedures vary between engines and drives, so always follow the service information for the exact application rather than applying one fill procedure to every outboard or sterndrive.

What to Check Before Ordering This Gear Lube Pump

• Bottle size and opening: Confirm that the gear lube uses a compatible standard quart bottle and pump-cap connection.
• Drain-plug thread: Verify that the main 3/8-16 fitting matches the gearcase or determine whether the 8 mm adapter is required.
• Engine or drive: Check the exact make, model, production range or serial information and lower-unit configuration.
• Gear-lube specification: Use only the lubricant type and viscosity specified for the application.
• Drain-plug gaskets: Replace sealing gaskets where required. For compatible Yamaha applications, see the Yamaha outboard lower-unit drain gasket.
• Service instructions: Confirm fill direction, vent-plug sequence, fill level, gasket requirements, and torque specifications in the manufacturer's service information.

Gear Lube Pump vs. Oil Extractor Pump

This product is designed primarily as a gear lube pump for transferring fresh lubricant from a quart bottle into a compatible lower unit or gearcase. It should not be confused with an oil extractor pump, which is primarily used to evacuate or remove engine oil, gear lube, or other service fluids from compatible systems.

If you need a tool for fluid removal rather than lower-unit filling, browse PartsVu's oil extractor pumps. For Yamaha lower-unit lubricants, pumps, and related service products, browse Yamaha gear lube and gearcase components.

Gear Lube Pump FAQs

What does a lower-unit gear lube pump do?

A gear lube pump transfers gear lubricant from a compatible bottle into a marine lower unit or gearcase through the specified fill or drain opening. Follow the engine or drive manufacturer's service procedure for the exact application.

Does this gear lube pump fit standard quart bottles?

Yes. This PartsVu quart bottle pump is designed for standard quart bottles with a compatible 28 mm or 1.125-inch opening. Confirm the bottle connection and gear-lube product before beginning service.

What drain-plug size does the PartsVu gear lube pump fit?

The main fitting is designed for 3/8-16 drain-plug applications. Because lower-unit fittings vary, verify the exact thread specification for your engine or sterndrive before ordering.

What is the included 8 mm adapter used for?

The included 8 mm adapter allows the pump to connect to compatible 8 mm lower-unit or gearcase applications. Check the engine or drive service information to confirm whether the adapter is required for your setup.

How do I confirm this gear lube pump fits my outboard?

Confirm the outboard make, model, year or production range, serial information where applicable, lower-unit drain-plug thread, required adapter, gear-lube specification, and manufacturer service procedure. Do not assume compatibility based only on the engine brand.

Note: Gear lube is sold separately. Clean the pump after service and use the included rubber cap to help keep it clean between uses.

WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to P65Warnings.ca.gov.