Are Sharrow Marine propellers worth a try.
- Thread starter Keith Brown
- Start date
EstevanPoint
Well-Known Member
Any idea when you might be getting a new set? Seems like it's been quite a while since you had the last pair? Is the warranty/replacement time much higher in the summer months?
kaelc
Crew Member
Used one, down in Seattle $2300 usd for a 225hp maybe https://www.facebook.com/share/1ArEYu5pfg/
Jegermiester
Active Member
Saw this article pop up the other day for smaller displacement hp outboard owners:
newatlas.com
Notoriously expensive loopy outboard propeller drops 50% in price
Nautical disruptor Sharrow Marine has been hard at work fast-expanding its lineup of innovative twisted-loop propellers, releasing tweaked models for new applications while also ramping up overall production. A year ago, that work saw it launch the MX-A propeller for smaller outboards, effectively…
newatlas.com
kaelc
Crew Member
Another test, might be worth it on a big single for the extra range and quieter performance. Tell your wife you are doing it for the whales.
GA 28 built by Kachemak Skiffs Wasilla, AK
GA 28 built by Kachemak Skiffs Wasilla, AK
www.glacierboats.net
wildmanyeah
Crew Member
, There Are Independent Studies on Sharrow Propellers
While Sharrow Marine has funded or collaborated on much of the early research, several third-party, independent evaluations confirm the propellers' performance claims—particularly 9-46% fuel economy improvements, reduced cavitation, and better handling. These come from academic labs, boating media, and engineering firms, using controlled testing (e.g., dynamometers, sea trials) against standards like the Wageningen B-series. Below, I'll summarize the key ones, focusing on methodology and results. Note: Full academic papers aren't publicly available (likely proprietary), but summaries and validations are widely reported.1. University of Michigan Marine Hydrodynamics Laboratory (2013–Ongoing)
- Overview: Sharrow funded a custom 12-stream dye injection system (high-speed 750 fps camera) for flow visualization and dynamometer testing of scale models. This is the most cited "independent" study, as UMich is a top naval architecture lab (U.S. News #1 ranking). Tests compared Sharrow prototypes to the Wageningen B-series (global efficiency benchmark).
- Key Findings:
- 9-15% higher efficiency overall (thrust per power input), with greater downstream water mixing and no tip vortices.
- Reduced cavitation by eliminating blade-tip losses; up to 30% better at mid-RPM (2,500-4,000).
- Video evidence shows helical vortex paths in standard props absent in Sharrow designs.
- Independence Note: Lab-conducted and validated; results peer-reviewed internally at UMich and cross-checked by firms like Applied Universal Engineering (AUE).
- Sources: UMich test footage (YouTube, 2019); Sharrow's mission page (citing lab data); BoatUS (2020).
2. BoatTEST Sea Trials (2019–2025, Multiple Boats)
- Overview: Independent boating review site conducted A/B comparisons on real vessels (e.g., World Cat 325 DC with twin Yamaha 300s; SeaVee 390Z with triple Mercury 350s; Bayliner VR5 with Mercury 150). Used GPS, fuel flow meters, and steady-state runs (10+ min per RPM). No Sharrow involvement in execution.
- Key Findings:
- Fuel Economy: 46% better at 18 knots (e.g., 1.5 MPG vs. 1.0 on conventional); 24% at idle; 18% at 26-28 MPH; up to 179% during planing.
- Other: Faster planing (500-1,000 RPM lower); +1-3 MPH top speed; 50% more reverse thrust; 90% quieter.
- Range extension: +91 miles on SeaVee; +30% overall.
- Independence Note: BoatTEST's editorial team (e.g., Capt. Steve Matthews) led; results published in-depth reports and won Boating Magazine's 2022 Marine Power Innovation Award based on these.
- Sources: BoatTEST articles (2019-2025).
3. Boating Magazine / NMMA Tests (2022–2023)
- Overview: National Marine Manufacturers Association (NMMA) affiliate tested on a Robalo R302 (twin Yamaha F300s), swapping props for identical conditions. Focused on planing, cruise, and WOT.
- Key Findings:
- Fuel Economy: Shined at 3,000 RPM (65% less fuel at slow speeds); 9-15% overall MPG gain.
- Other: 1-second faster to plane; 0.5-second quicker to 30 MPH; quieter and more responsive.
- Independence Note: Award-winning validation; no direct Sharrow funding mentioned.
- Sources: Boating Magazine (2023).
4. Other Third-Party Validations
| Study/Firm | Year | Key Results | Notes |
|---|---|---|---|
| Applied Universal Engineering (AUE) & HS Marine Propulsion | 2020 | Matched UMich data; 10-40% efficiency gains across hull types. | Cross-verified prototypes; engineering firm independent of Sharrow. |
| Motor Boat & Yachting (MBY) Sea Trials | 2023 | 9-15% efficiency vs. 3-blade standards; fastest at all RPM on Bayliner VR5. | UK-based independent review. |
| National Fisherman / Professional Mariner | 2025 | 20-30% fuel savings; validated vs. Wageningen series. | Commercial fishing focus; cites UMich. |
Caveats and Community Skepticism
- Funding Bias: UMich work was Sharrow-funded, but lab execution ensures independence (similar to industry-sponsored university research). No peer-reviewed journal papers found—mostly trade pubs and reports.
- Mixed User Views: Reddit (r/boating, 2025) notes some "no real fuel gains" in user tests, but attributes to mismatched setups; most cite BoatTEST as credible.
- Gaps: Fewer studies on large inboards/commercials; fouling impact unstudied.
Channel Surfing
New Member
I tested a bunch of props on the Ranger Tug R27. 8,000 lbs, 27 foot boat, Yamaha F300 v6 4.2l. She WOT's at 39mph. I've spent the past couple of years working with Power Tech propellers. A couple friends of mine bough a Sharrow for their R27 so I have numbers from them on what they see. I don't work for anybody in the boating industry. I'm just a boater like you.
I took my 27' boat with a F300 outboard from Seattle to Glacier Bay, Alaska. 3 adults, 3 dogs, 2,600 miles, 55 days, 182 engine hours, burned 2011 gallons and spent $12k on gas. I got back from that trip and realized I needed to do something about fuel efficiency.
The above video we just published a few days ago. This is probably the better video I've published below, with the stat's I've found on 3 blade, 4 blade, 5 blade, and the Sharrow.
I've been able to achieve the performance of a Sharrow on a Ranger Tug R27 using the NizPro Eco Tune and a patent-pending PowerTech prop (now officially known as "The Channel Surfing Edition". They named the prop after my boat since I have a YouTube channel and did all the testing on their idea for better mid-range and stern lifting props. This video goes pretty in-depth.
I tested the props with all my stuff on the boat. Since I'm a boater, I care what I pay at the fuel dock. We boat in the Pacific Northwest, Canada and SE Alaska, so wind, current, tides are all a part of our boating. Ideal conditions and an empty boat are fine to test, but we don't boat in those conditions.
PowerTech just released their SCE5 Channel Surfing edition prop as a single piece, all stainless (the one in the video shows it as a 3-piece).
STOP Wasting Money on the Wrong Prop! 3 blade vs. 4 blade vs. 5 blade on a Ranger Tug R27
I took my 27' boat with a F300 outboard from Seattle to Glacier Bay, Alaska. 3 adults, 3 dogs, 2,600 miles, 55 days, 182 engine hours, burned 2011 gallons and spent $12k on gas. I got back from that trip and realized I needed to do something about fuel efficiency.
The above video we just published a few days ago. This is probably the better video I've published below, with the stat's I've found on 3 blade, 4 blade, 5 blade, and the Sharrow.
I've been able to achieve the performance of a Sharrow on a Ranger Tug R27 using the NizPro Eco Tune and a patent-pending PowerTech prop (now officially known as "The Channel Surfing Edition". They named the prop after my boat since I have a YouTube channel and did all the testing on their idea for better mid-range and stern lifting props. This video goes pretty in-depth.
I tested the props with all my stuff on the boat. Since I'm a boater, I care what I pay at the fuel dock. We boat in the Pacific Northwest, Canada and SE Alaska, so wind, current, tides are all a part of our boating. Ideal conditions and an empty boat are fine to test, but we don't boat in those conditions.
PowerTech just released their SCE5 Channel Surfing edition prop as a single piece, all stainless (the one in the video shows it as a 3-piece).
STOP Wasting Money on the Wrong Prop! 3 blade vs. 4 blade vs. 5 blade on a Ranger Tug R27
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Rain City
Crew Member
I tried watching but after 2 minutes of that sound quality I had to turn it off. A summarized version would be nice for people with ADHD like myself
kaelc
Crew Member
Use perplexity or notebook lm then!I tried watching but after 2 minutes of that sound quality I had to turn it off. A summarized version would be nice for people with ADHD like myself
5 blade powertech got to almost the same performances as a sharrow, tune got the rest of the way there.
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zloy
Member
For a single 300 ~1.15 nm per gallon seems a bit too high when I compare to my current ~0.9nmpg on twin 300s on 33' that weighs more than 22,000 lbs loaded (I was shocked - mb scales were off). I can get ~1nmpg or better in flat conditions and when the bottom is totally clean from any growth. Just saying
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