Express Mach4 Propeller 14.5x17 – 4-Blade Stainless Steel, LH Rotation | 90–300+hp (4.75" Gearcase)
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Express Mach4 Propeller — 14.5 x 17, 4-Blade Stainless Steel, Left-Hand Rotation
The Express Mach4 is a premium 4-blade stainless steel propeller engineered with a patented Dual Geometry design — delivering the hole shot, handling, and load-carrying advantages of a 4-blade without the top-end speed penalty that typically comes with it. Built for high-horsepower outboards and sterndrives from 90 to 300+hp with 4.75-inch gearcases.
This is the left-hand (counter-rotation) version. For twin-engine setups, pair with the Express Mach4 14.5x17 RH Rotation.
Best Use Case
The 17-pitch Mach4 is the ideal all-around choice for watersports boats, tri-toons, bay boats, and sterndrive applications where you need strong acceleration, confident cornering, and the ability to carry a full load without losing top-end speed. It’s particularly well-suited to twin-engine setups running counter-rotating props, and to any application where stern lift and rough-water stability matter as much as straight-line speed.
Dual Geometry — How It Works
Most 4-blade props sacrifice top speed for better hole shot. The Mach4 solves this with two distinct blade geometries in a single hub: two blades use an aggressive variable-rake design for explosive acceleration and cornering grip, while the other two use an offshore-style design for high-speed efficiency and maximum stern lift. The result is a 4-blade that matches 3-blade top-end speed while outperforming it in every other condition.
Key Features
- TP17™ Proprietary Stainless Steel — Formulated specifically for the Mach4 series. 20% higher chromium content than standard stainless for better corrosion resistance and a higher-gloss finish. Nearly 250% stronger and 5x more durable than conventional stainless steel alloys.
- 4-Blade Dual Geometry Design — Two blade geometries in one prop: aggressive rake for hole shot and handling, offshore profile for speed and stern lift. No top-end speed loss versus a comparable 3-blade.
- Full Hull Lift — Raises the entire hull higher out of the water, reducing wetted surface and maintaining top speed even under heavy loads where a 3-blade can lose up to 3 mph.
- Exceptional Rough-Water Stability — The 4-blade configuration damps out chop and improves tracking in confused seas, reducing driver fatigue on longer runs.
- Large Exhaust Ports — Oversized exhaust flow pathways reduce back-pressure and free up horsepower at wide-open throttle.
- Compatible Engine Brands — Fits COX, Evinrude, Honda, Johnson, Mariner, Mercury, MerCruiser, Nissan, OMC, OXE, Parsun, Suzuki, Tohatsu, Volvo Penta, and Yamaha outboards and sterndrives.
Specifications
- Part Number: 31501741
- Diameter x Pitch: 14.5" x 17"
- Blades: 4
- Material: TP17™ Stainless Steel
- Rotation: Left-Hand (Counter-Rotation)
- Gearcase: 4.75" (large)
- Compatible Engine Range: 90–300+hp outboards & sterndrives
- Hub System: 500-Series hub kit (under 200hp) or 700-Series hub kit (200hp+) required — sold separately
Parts Desk Insights
Hub kit required — not included. This propeller requires either a 500-Series or 700-Series hub kit depending on your engine’s horsepower. Confirm your engine make, model, and year against the application chart to select the correct kit before ordering.
LH rotation — confirm your application. Left-hand rotation props are used on the port side of counter-rotating twin-engine setups, or on specific single-engine applications that call for counter-rotation. If you’re running a single standard outboard, you almost certainly need the RH version. See the Express Mach4 14.5x17 RH Rotation if unsure.
If you’re choosing between pitch options, 17-pitch is the most versatile starting point for this gearcase family. Step down to a 15-pitch for more aggressive acceleration and load carrying, or up to a 19-pitch for higher top-end speed on lighter, faster hulls. Browse the Mach4 lineup by pitch:
- Express Mach4 15 x 15 — 4-Blade SS, RH
- Express Mach4 15 x 15 — 4-Blade SS, LH
- Express Mach4 14.5 x 17 — 4-Blade SS, RH
- Express Mach4 14 x 19 — 4-Blade SS, RH
- Express Mach4 14 x 21 — 4-Blade SS, RH
- Express Mach4 14 x 23 — 4-Blade SS, RH
Also available in the 3-blade Mach3 configuration for this pitch: Express Mach3 14.25 x 17 — 3-Blade SS, LH.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.