This listing is for a new 5-inch Outboard Extension Kit manufactured by Bay Manufacturing for select Johnson & Evinrude 100–300 HP outboard motors. Each kit adds 5 inches to your motor and is engineered using high-strength materials designed for long-term marine use.
Some spacer housings may arrive painted black, while others are unpainted with a clean sandblasted finish. Finish may vary. Each kit includes a 1-year manufacturer warranty.
⚠ Important: Extension kits DO NOT fit Generation 2 engines. Compatibility is limited to Generation 1 models only, as outlined below.
Product Features
- Adds 5 inches to outboard motor length
- Designed for Johnson & Evinrude 100–300 HP applications
- Stainless steel shafts and studs for corrosion resistance
- Spacer housing cast from the same alloy series used in original motors
- Complete kit with all required components for conversion
- Manufactured by Bay Manufacturing
Fitment Information
YOUR MOTOR MUST MATCH ALL LISTED SPECIFICATIONS TO FIT THIS KIT
General Notes
- ❌ Does NOT fit Generation 2
- ✅ Fits Generation 1 only
- High Output models require a double O-ring water tube (see table notes)
Compatible Horsepower & Year Ranges
| Horsepower | Year(s) |
|---|---|
| 100 HP V4 | 1985 |
| 100 HP | 1986–1988, 1992–1995 |
| 100 WPT | 1989 |
| 120 HP V4 | 1985 |
| 120 HP | 1993–1994 |
| 125 HP | 1990–1994 |
| 130 HP | 1995–2009 |
| 135 HP | 1995–2009 |
| 135 ETEC | 2004–2020 |
| 140 HP V4 | 1985 |
| 140 HP | 1993–2009 |
| 140TX | 1988–1992 |
| 150 HP V6 | 1985 |
| 150 HP | 1986–2009 |
| 150 ETEC | 2004–2020 |
| 155 HP V6 | 1985 |
| 155 HP | 1986–1987, 1989, 1991–1992 |
| 175 HP V6 | 1985 |
| 175 HP | 1986–2009 |
| 175 ETEC | 2004–2020 |
| 185 HP | 1991–1994 |
| 200 HP | 1986–2009 |
| 200 ETEC | 2004–2020 |
| 225 HP | 1986–2009 |
| 225 ETEC | 2004–2020 |
| 235 HP V6 | 1985 |
| 250 HP | 1995–2009 |
| 250 / 275 / 300 ETEC | 2004–2020 |
Notes:
- Asterisked models are Generation 1 only
- High Output ETEC models require a double O-ring water tube
Kit Specifications
- Extension Length: 5 inches
- Paint Color: Unpainted (paintable) or black (finish may vary)
- Manufacturer: Bay Manufacturing
- Kit Series: 507
- Horsepower Range: 100–300 HP
Parts Included
- (1) 5″ Housing
- (1) Exhaust Stack
- (1) Plastic Tube
- (1) 5″ Driveshaft
- (1) 5″ Shift Shaft
- (1) 5″ Water Tube
- (5) Studs and Nuts
- (1) Socket Screw
- (1) Tube
Returns & Warranty
- 1-Year Manufacturer Warranty
- Not eligible for return for any reason other than a valid warranty claim
Shipping Information
Additional shipping fees apply for Alaska, Hawaii, U.S. Territories, and International orders.
International shipping is calculated after checkout. Customers will receive an email and a PayPal money request for any additional shipping charges.
(Some items are excluded from international shipping.)
Customer Support
For questions or to confirm compatibility, please email customerservice@marinepartswarehouse.com .
Please include your engine model or serial number to help confirm proper fitment before ordering.
