STOP Wasting Money on the Wrong Prop

[@dhansen68]

Well done Martin. Probably the most thorough unbiased prop reviews I've seen.

[@Letsgochannelsurfing]

Thank you for the feedback! It takes a lot of work to put something like this together. I'm glad you found it helpful.

[@kflockto]

Thanks Martin Great info I plan to call Power Tech and see what they recommend for my R25

[@Letsgochannelsurfing]

It's possible that the SCE5 will work on the R25. I know of a guy who bought a stock SCE5 (no modification), and has it on his R25 and likes it. But give PowerTech a call and see what they think.

[@georgesilverman1105]

Awesome job Martin. We get our new 27 in two weeks.

[@Letsgochannelsurfing]

Congratulations on your new boat! So exciting!

[@johnkroetch4559]

Nice to see you and your amazing sense of detail, Martin. I use your advice perpetually for a RT25. Not the exact same boat, but you give me a great place to start. Already using the Power Tech for Lake WA shenanigans and inner-tubing. For trips to the San Juans I always put the factory prop back on - it's the same prop even though our motor is 250 HP - but the fuel savings is worth the 10 minute chore of swapping props. Happy New Year.

[@Letsgochannelsurfing]

Thanks, glad to hear my advice is helping!

[@tomw7863]

Hi, what factory prop did your R25 come with? My 2025 R25 came with a Yamaha SWII, but it’s 15.5 x 16P.

[@Letsgochannelsurfing]

@@tomw7863 Every R25-OB I've seen, it's a Yamaha SWS II 15.5 x 16. Reel Magic has that on her as well.

[@tomw7863]

The Nevermoor is usually loaded pretty heavily, we only get 5300-5400 RPM at WOT (probably could trim better). I wonder if we should go down in pitch. Maybe I’ll look at that when we get an SCE5.

[@Bryan-q6s8m]

Thank you Martin.

[@Letsgochannelsurfing]

Thanks for watching!!

[@anniethurman-f5j]

Great detail Martin. Looking forward to running one on our boat.

[@Letsgochannelsurfing]

Hope you enjoy it!

[@fmb-fishingmeansbusiness]

Thanks for the deep dive. I've always liked the ranger tug but would prefer a 26 foot boat with a 10 foot beam if I ever move up in size. On my boat this week I'm going to a 4 blade from a 3 blade and 1/2 inch smaller and 13 to 15p. Looking forward to seeing how it performs on my C-Dory 25. I can hit 3mpg but usually do 2.5mpg loaded at 20mph.

[@Letsgochannelsurfing]

Thanks for watching. Let me know how the prop swap works out.

[@hondarideralex]

Talked with Marcus about your prop I think a monthcor so ago. We have used their props for various engines over the years. Good stuff.

[@Letsgochannelsurfing]

Marcus is fantastic to work with. PowerTech makes good stuff.

[@jacktyler7599]

Great presentation, Martin. Gives me hope I can improve the mileage I'm seeing on our Cutwater 248 with its 250. Thank you.

[@Letsgochannelsurfing]

I hope it helps you out!

[@KieranCox]

Great vid. I will say I think you missed a critical selection. Yamaha (IMHO) makes the best 4 blade prop for the F300 engine. For hull speeds and moving a heavy boat at cruising speeds. You loose a bit topend though, my topend came down from 52mph to about 45mph (totally not needed topend really). I replaced the props on both my F300s on my 32CB with the Yamaha TURBO OFFSHORE 1 Propeller. Never looked back afterwards. Much improved hole-shot and tons more torque. I don't think the Rangers have the planning issue the Cutwaters have when loaded down, but this prop solved my issue with a bunch of people on board easily.

[@Letsgochannelsurfing]

I did briefly look at Yamaha for their 4 blades. The R27-OB gets up on plane with the Yamaha SWSII 3 blade. But it takes a long runway to get up. It also can't really operate in the mid-range as it falls off plane. 4 or 5 blade prop's solve this. The Cutwater hull is a double stepped hull while the Ranger hulls aren't. This project really started out looking at the Sharrow and asking the question "How close can we get to the performance of a Sharrow in a conventional 4 or 5 blade prop". The SCE5 Modified gets close.

[@KieranCox]

​@@Letsgochannelsurfing Hmm, sounds like the same effect as with the Cutwater hulls with the SWSII 3 blade. I always thought it was due to the steps, but perhaps it isn't. The Sharrows are great, right up until you notice the price to buy and the cost to repair... Juice is not worth the squeeze at $5k/each.($10k in propellers for me with dual engines) Now if they were under $1k each, they'd definitely be worth it. They want $400/year PER A PROPELLER for their protection plan??? LOL I ran some numbers through ChatGPT on how many miles at hull speeds it would take to recover my costs on the Sharrow props... at $5/gallon the AI came up with ~24,000 miles(3000hours!) as the break even point! LOL!!!! It would take around 500 hours of 30mph cruising to break even (which I rarely do) If I want to be cheap on fuel I just set my autopilot to 8mph, shut down and lift one engine out the water. I get nearly 2.8mpg in that "Eco-mode" setup with the 4blade Turbo Offshore prop. A propeller doesn't need to get close to make the cost of Sharrows look silly!

[@Letsgochannelsurfing]

@@KieranCox This is great information! I love hearing feedback from other outboard owners ,especially from a Cutwater 32CB. I've also done the ROI calculator on a Sharrow vs the SCE5-Modified, as really the only difference I see between them is fuel efficiency. A friend of mine ran 488 gallons of fuel through his Sharrow on his R27-OB (897 miles) and averaged 1.84mpg for the summer. I'm averaging 1.60mpg. ChatGPT tells me it would take 9,756 miles to break-even (ROI). Channel Surfing, as of today, has traveled 11,985 miles and has 895 engine hours. I also ran the math through ChatGPT for what if gas was $4/gal? It's over 12,000 miles to break-even. As gas goes down in price, the longer it'll take to break even. At $8/gal it's still over 6,000 miles to break even. Crazy.

[@bigpapaporsche1]

We are considering a used R25SC (Ideally a Yanmar Diesel) for primarily fresh water use and the occasional trip to the Gulf during the Winter months. I don't understand how "Ranger" can call their boats "Tugs" when they can go so FAST! Sure they look like a Tug/Trawler, but are they really? I guess the Marketing Department game up with that name. IMHO, I would prefer less HP/Cost and would be more than willing to sacrifice Speed to achieve this objective. Its like the guy who wants to reduce his Heating/Cooling costs at home, but never considers a small house!

[@tomw7863]

Hey Martin, how’d you determine sizing between the SWSII, the OFS4, and the SCE5? To go from 15.75” stock to 14” on the SCE5 seems like a jump. Did you try any other sizes?

[@Letsgochannelsurfing]

I worked with PowerTech on sizing. The SCE comes in a 3, 4 or 5 blade version. They are all 14" diameter. The OFS comes in a 3, 4 or 5 blade version, and they are all 15.25" diameter. The SCE and OFS are available in 14" and larger pitch on the blades. For boats our size, 15 pitch seems to work the best. Clifford tried an OFS 4 blade, 14 pitch on his boat (R27-OB). I have numbers off it. It's worse than the OFS4 15 pitch. This is where the trial and error part comes in. I think most of us were surprised at how well a 14" diameter prop (The SCE) actually performed. There's a lot of magic that goes into the prop blade geometry. The SCE with it's semi-cleaver blades vs the big lobes with lots of cup on the OFS4 (offshore style blades). Both style of blades were designed for stern lift. They just go about it a different way. There's some guidelines the prop shop and prop manufactures use when going up or down in diameter, and when going from 3 to 4 blades, or 4 to 5 blade. Like, how much to alter pitch or diameter. Powertech discussed maybe making the SCE5 in a bigger diameter to try, but that's creating a new prop completely. I'd be worried that a larger diameter means more suface area in contact with the water which will probably lower the WOT RPM's. Those need to be 5500 - 6000 RPM and the SCE5-15 comes in at 5600, so I don't have much room to go lower. We've already recorded "Cost of Boat Ownership" on our R27-OB, to be published within a week or two. LaZina's editing it. There's a slide on that video that shows 5 years of fuel usage (mpg, gph, miles, cost of fuel, etc...). I have 2 years on a 3 blade, 2 years on the 4 blade, and 1 year on the 5 blade. I'll post this slide over on Patreon. If you want to test it, bring your boat up to Everett and I'll let you try my SCE5-15 Modified for a trip around Hat Island. I think the SCE5-15 Modified will work on an R25-OB as is... but won't know for sure unless we test it. Maybe the R25-OB would need a 16 pitch instead of 15, only testing it will know for sure.