Lower Unit Seal Kit Oil Seal 26-161622 for Mercury Mariner 9.9 15 20HP Outboard
Lower Unit Seal Kit Oil Seal 26-161622 for Mercury Mariner 9.9 15 20HP Outboard
Product Overview
Lower unit seal kit for Mercury and Mariner 9.9HP, 15HP and 20HP outboards. It replaces Mercury Marine 26-161622 and ships as one oil seal, one O ring, three drain gaskets and a cotter pin in a 150 mm x 180 mm x 40 mm box at 21 g.
This is the sealing set for the small gearcase on the portable and mid range motors. The oil seal sits on the prop shaft, the O ring seals the carrier, the three gaskets go under the drain and fill screws, and the cotter pin locks the propeller nut.
On a small motor the gearcase holds very little oil, so a slow leak turns to milky oil within a few trips. By the time it is brown there is usually water sitting against the bearings, and the repair goes from a set of seals to a gearcase rebuild.
Fitment covers the Mercury and Mariner 9.9HP, 15HP and 20HP models. Mercury built the same gearcase under both badges, so the kit covers either. Check the model and serial number before ordering, because the larger 25HP and 30HP gearcases take different seals.
Specifications
| Specification | Detail |
|---|---|
| Condition | New / New with tags |
| Type | Lower unit seal kit |
| Mercury Oil Seal | 26-161622 |
| Fits | Mercury and Mariner outboards |
| Fits Horsepower | 9.9HP, 15HP and 20HP |
| Package Contents | 1 x oil seal, 1 x O ring, 3 x drain gasket, 1 x cotter pin |
| Net Weight | 21 g including packaging |
| Pack Size | 150 mm x 180 mm x 40 mm |
| Pack Size In Inches | 5.91 in x 7.09 in x 1.57 in |
| Warranty | 3 year |
OEM Cross Reference
| Brand | Part Numbers |
|---|---|
| Mercury Marine | 26-161622 (oil seal) |
Compatible Engines
| Horsepower | Engine | Position |
|---|---|---|
| 9.9HP | Mercury Mariner two stroke | Lower unit, prop shaft |
| 15HP | Mercury Mariner two stroke | Lower unit, prop shaft |
| 20HP | Mercury Mariner two stroke | Lower unit, prop shaft |
What's Included
| Component | Part Number Or Size | Qty |
|---|---|---|
| Oil seal, prop shaft | 26-161622 | 1 |
| O ring seal | 25-8M0087846, 803735 | 1 |
| Drain and fill gasket | 8M0082880 | 3 |
| Cotter pin | 8150264 | 1 |
| Gear oil | Not included, sold separately | 0 |
Signs The Seals Have Gone
| What You See | What It Means | What To Do |
|---|---|---|
| Milky gear oil on the dipstick | Water past the prop shaft seal | Fit the full kit |
| Oil film around the propeller | Outer seal leaking | Fit the full kit |
| Gear oil drops after each trip | Seal weeping under load | Fit the full kit |
| Water when the gearcase is drained | Drain screw gasket or O ring failed | Fit the full kit |
| Rumble from the gearcase | Bearings running on watered oil | Fit the full kit and check the gears |
| Fresh seal failed in a season | Other seals left in place | Fit the full kit |
Fitting Notes
| Step | Action |
|---|---|
| 1 | Read the model and serial number off the motor and check the table above |
| 2 | Drain the gear oil and note the colour before going further |
| 3 | Take off the propeller, nut, washer and carrier |
| 4 | Prise the old seal out squarely without scoring the bore |
| 5 | Check the shaft where the seal lip runs for a wear groove |
| 6 | Fit the new seal with the lip toward the oil side and drive it square |
| 7 | Fit the new O ring and the drain and fill gaskets dry |
| 8 | Pressure test the gearcase before refilling |
| 9 | Fill with the specified gear oil, fit a new cotter pin and check after a run |
Condition & Warranty
| Item | Detail |
|---|---|
| Condition | New / New with tags |
| Warranty | 3 year |
| Packaging | Boxed, 150 mm x 180 mm x 40 mm |
Before You Buy
- Fits Mercury 9.9HP, 15HP and 20HP outboards
- Fits Mariner 9.9HP, 15HP and 20HP outboards
- Replaces Mercury Marine oil seal 26-161622
- One oil seal, one O ring, three gaskets and a cotter pin
- For the small gearcase, not the 25HP or 30HP motors
- 21 g with packaging, box 150 mm x 180 mm x 40 mm
- 30-Day Easy Returns
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Boat Owners' Review
Before You Buy
Frequently Asked Questions
What is your refund policy?
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See our full Refund Policy for complete details.
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