Product Overview
Sierra Marine engine parts are designed to meet or exceed the OEM part they are intended to replace and they are backed by the SeaStar Solutions Two-Year Warranty—one of the best in the business.
We offer a variety of O-rings, oil seals and seal kits for most engine applications on the water today—including MerCruiser, OMC, Johnson/Evinrude, Volvo and more.
How to find the O-ring you need
Many of the O-rings we offer fit multiple applications. Notice in the list below that in addition to Mercury Marine and OMC applications, there are a variety of other engine applications for the O-rings offered here. O-rings can also be selected by inside diameter and width, which also appear in the table.
The Sierra Engine Parts Selector
If you do not see the O-ring (or other engine part) you need, please visit the Sierra Engine Parts Selector, where you can search by engine make, model, serial number or year of manufacture.
| Sierra # | Application | Replaces OEM Part # | I.D. | Width | Qty. | Model |
|---|
| 18-7421-9 | Mercury Marine | 25-20415 | 0.150" | 0.065" | 5 | 10519650 |
| 18-7421- 9 | GLM | 80070 | 0.150" | 0.065" | 5 | 10519650 |
| 18-7426- 9 | Mercury Marine | 25- 30271 | 0.740" | 0.310" | 2 | 10518884 |
| 18-7426- 9 | GLM | 21330 | 0.740" | 0.310" | 2 | 10518884 |
| 18-7426- 9 | Mallory | 9-76562 | 0.740" | 0.310" | 2 | 10518884 |
| 18 -7426-9 | Mercruiser Stern Drive | 25- 30271 | 0.740" | 0.310" | 2 | 10518884 |
| 18-7426-9 | Mercury Sport Jet | 25-30271 | 0.740" | 0.310" | 2 | 10518884 |
| 18-7445- 9 | Mercruiser Stern Drive | 25- 55801 | 0.801" | 0.070" | 2 | 10518918 |
| 18-7445- 9 | Mallory | 9-76568 | 0.801" | 0.070" | 2 | 10518918 |
| 18 -7445-9 | GLM | 80190 | 0.801" | 0.070" | 2 | 10518918 |
| 18 -7420-9 | Mercury Marine | 25- 21836 | 0.796" | 0.139" | 5 | 10519643 |
| 18-7420-9 | Mercruiser Stern Drive | 25-21836 | 0.796" | 0.139" | 5 | 10519643 |
| 18-7420 -9 | Mallory | 9- 76565 | 0.796" | 0.139" | 5 | 10519643 |
| 18-7420- 9 | GLM | 82110 | 0.796" | 0.139" | 5 | 10519643 |
| 18-7420- 9 | Mercury Sport Jet | 25- 21836 | 0.796" | 0.139" | 5 | 10519643 |
| 18- 7474 | GLM | 84026 | 1.239" | 0.070" | 1 | 10518736 |
| 18- 7474 | Mercruiser Stern Drive | 25- 94288 | 1.239" | 0.070" | 1 | 10518736 |
| 18-7171- 9 | GLM | 81360 | 1.920" | 0.100" | 5 | 10519288 |
| 18-7171- 9 | Mercruiser Stern Drive | 25- 30529 | 1.920" | 0.100" | 5 | 10519288 |
| 18-7171-9 | Mercury Marine | 25-30529 | 1.920" | 0.100" | 5 | 10519288 |
| 18-7414- 9 | GLM | 80330 | 1.989" | 0.070" | 5 | 10519585 |
| 18-7414- 9 | Mercury Marine | 25- 62384 | 1.989" | 0.070" | 5 | 10519585 |
| 18-7414-9 | Mercury Sport Jet | 25-823683 | 1.989" | 0.070" | 5 | 10519585 |
| 18- 7459 | GLM | 82280 | 2.234" | 0.139" | 1 | 1764190 |
| 18- 7459 | Mercruiser Stern Drive | 25- 20826 | 2.234" | 0.139" | 1 | 1764190 |
| 18-7459 | Mercury Marine | 25-20311 | 2.234" | 0.139" | 1 | 1764190 |
| 18- 7459 | Mercury Sport Jet | 20826 | 2.234" | 0.139" | 1 | 1764190 |
| 18-7177- 9 | GLM | 80380 | 2.625" | 0.065" | 5 | 10519346 |
| 18-7177- 9 | Mercruiser Stern Drive | 25- 59712 | 2.625" | 0.065" | 5 | 10519346 |
| 18-7160- 9 | GLM | 83340 | 2.635" | 0.210" | 5 | 10519205 |
| 18-7160- 9 | Mallory | 9-76545 | 2.635" | 0.210" | 5 | 10519205 |
| 18 -7160-9 | Mercruiser Stern Drive | 25- 31986 | 2.635" | 0.210" | 5 | 10519205 |
| 18-7160-9 | Mercury Marine | 25-31986 | 2.635" | 0.210" | 5 | 10519205 |
| 18-7419- 9 | Chrysler/Force/US Marine | 25- 69202 | 2.675" | 0.103" | 5 | 10519635 |
| 18-7419- 9 | GLM | 81470 | 2.675" | 0.103" | 5 | 10519635 |
| 18-7419- 9 | Mallory | 9-76564 | 2.675" | 0.103" | 5 | 10519635 |
| 18 -7419-9 | Mercury Marine | 25- 69202 | 2.675" | 0.103" | 5 | 10519635 |
| 18-7415- 9 | GLM | 80440 | 3.739" | 0.707" | 5 | 10519593 |
| 18-7415- 9 | Mercruiser Stern Drive | 25- 64966 | 3.739" | 0.707" | 5 | 10519593 |
| 18-7415-9 | Mercury Marine | 25-64966 | 3.739" | 0.707" | 5 | 10519593 |
| 18- 7464 | GLM | 82240 | 4.234" | 0.139" | 1 | 10518710 |
| 18- 7464 | Mercruiser Stern Drive | 25- 846361 | 4.234" | 0.139" | 1 | 10518710 |
| 18-7464 | Mercury Marine | 25-39695 | 4.234" | 0.139" | 1 | 10518710 |
| 18- 7449 | GLM | 81570 | 4.487" | 0.103" | 1 | 10518678 |
| 18- 7449 | Mallory | 9- 76581 | 4.487" | 0.103" | 1 | 10518678 |
| 18-7449 | Mercruiser Stern Drive | 25-97387 | 4.487" | 0.103" | 1 | 10518678 |
| 18- 7124 | Mercury- Mariner | N/A | 2.500" | 0.103" | 1 | 10517985 |
| 18- 7125 | Mercury- Mariner | N/A | 2.300" | .103" | 1 | 10517993 |
