Lower Unit Gear Oil Pump with 3/8-inch, 8mm & 10mm Adapters

Fill a compatible lower unit from a standard quart bottle with the JLM Marine gear oil pump. The manual pump includes a clear hose, three metal fitting sizes and two suction tubes for different bottle heights. Check both the bottle neck and your engine's oil-port threads before ordering.

Lower Unit Gear Oil Pump Specifications

• Bottle fit: standard quart bottles with a 28mm neck. Not suitable for 38mm wide-mouth bottles.
• Fittings: 3/8-inch swivel fitting, 8mm metal adapter and 10mm metal adapter.
• Clear hose: approximately 19.88 inches, allowing you to see the lubricant as it moves through the hose.
• Suction tubes: 13cm (5.12 inches) and 15cm (5.9 inches). Choose the length that reaches the oil in your bottle.

Choose the Adapter by Oil-Port Thread

Engine brand alone does not establish fitment. Check your engine model, year and lower-unit drain/fill-port thread diameter and pitch. A fitting must thread in smoothly by hand; do not force it.

Shopping for a Mercury, MerCruiser, Yamaha, Honda or Suzuki engine? Do not select an adapter solely from the brand name. This kit is not a confirmed fit for every model from these manufacturers.

Package Content

• 1 manual gear oil pump
• 1 clear fill hose with 3/8-inch swivel fitting
• 1 × 8mm metal adapter
• 1 × 10mm metal adapter
• 2 suction tubes: 13cm and 15cm
• 2 sealing washers and 1 hose clamp

The pump has a built-in bottle attachment; a separate cap adapter is not listed as an included accessory. Check washer size against your application before use.

How to Use

1. Follow your engine manufacturer's service manual to drain the old gear oil and inspect the drain and vent plugs.
2. Fit the appropriate suction tube, attach the pump to a compatible bottle and secure the hose connections.
3. For lower units that specify bottom-up filling, connect the matching adapter to the lower fill port and pump until lubricant reaches the upper vent.
4. Refit the vent and drain plugs in the sequence specified by your manual. Use the correct seals and tightening torque, then check for leaks.

Use the lubricant grade, quantity and service interval specified for your engine. These vary by model.

Need help checking fitment? Send JLM Marine your engine make, full model, year and serial number, plus the oil-port thread specification if available, before ordering.