Description
SeaStar BayStar Outboard Cylinders
Wholesale Marine has a wide range of engine parts and steering components for outboard motors for all your repair, maintenance, and upgrading needs.Upgrading your mechanically steered boats is easy. The Baystar Outboard Cylinder manufactured by Seastar and continues to bring safety, comfort, and tradition to boating. Its superior design is manufactured to create smooth comfortable steering for your smaller outboard engines rated up to 150 HP (Total). Baystar uses only the finest materials and precision manufacturing. The outboard cylinder’s compact design and affordability make it an ideal solution. Developed for fast easy installation, it fits most splashwall and allows full engine movement. Baystar cylinders are not intended for use with high speed performance type boats and should consider SeaStar cylinders.** Mercury Optimax should use SeaStar Cylinders
| MANUFACTURER | YEAR | MODEL | CYLINDER | NOTES |
| FORCE | 1985–DATE | 90–150 HP | HC4645H | |
| HONDA | 1992–DATE | 30–90 HP | HC4645H | |
| 1998–2009 | 115–130 HP | HC4647H | ||
| 2001–DATE | 150 HP | HC4645H | ||
| 2003–DATE | BF135 HP | HC4645H | ||
| 2010–DATE | 115–150 HP | HC4645H | ||
| JOHNSON / EVINRUDE | 1977–1989 | 65–150 HP | HC4648H | |
| 1991–DATE | 40–150 HP | HC4645H | ||
| 1997–DATE | 115 HP FICHT | HC4658H | See Notes 4, 5 | |
| 1997–DATE | 75–150 HP FICHT | HC4645H | ||
| 1998–DATE | 40–140 HP 4-Stroke | HC4658H | See Notes 1, 4 | |
| MERCURY/MARINER | 1984–DATE | 75–150 HP | HC4645H | |
| NISSAN | 1990–DATE | 120–140 HP | HC4645H | |
| SUZUKI | 1986–DATE | 150 HP | HC4645H | |
| 1996 ONLY | 115–140 HP | N/A | ||
| 1987–2002 | 115–140 HP | HC4645H | See Note 1 | |
| 1990–2000 | 90–100 HP | HC4645H | ||
| 1998–DATE | 40–70 4-Stroke | HC4645H | See Note 1 | |
| 2001–DATE | 115–140 HP 4-Stroke | HC4658H | See Notes 1, 4 | |
| TOHATSU | 1990–DATE | 140–140 HP | HC4645H | |
| YAMAHA | 1998–DATE | 40–50 HP | HC4645H | See Note 2 |
| 1998–DATE | 60 HP | HC4645H | See Note 3 | |
| 1986–DATE | 70–90 HP | HC4645H | See Note 1 | |
| 1997–DATE | 80–150 HP 4-Stroke | HC4645H | ||
| 2000–DATE | 25–60 HP 4-Stroke | HC4648H | See Note 1 | |
| 2010–DATE | 70HP 4-Stroke | HC4648H | ||
| 1997–2013 | 115A 4-STROKE | HC4658H | ||
| 2014-DATE | 115B 4-STROKE | HC4645H | ||
| YANMAR | 1990–DATE | 27–36 HP | HC4645H |
Notes
- Requires Spacer kit part HO5090
- Engine clamp brackets must be cut or ground, and the engine through bolted onto the transom, or interference will occur, restricting engine trim and tilt.
- Steering hook Yamaha Part 63D-48511-00-4D must be installed
- Cylinder HC4645 may be used in these applications. The pivot plate will need to be flipped before installation. Instructions provided with Owner’s Manual.
- Johnson 115 HP 2-Stroke engines, require the pivot plate to be flipped. See Note 4.
California Residents: WARNINGCancer and Reproductive Harm – P65Warnings.ca.gov


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