Drop to 60 gallons, and up 20 hours and you'll see 6100, 44kts and 3.5
mpg. My buddy repowered his heavier 24 Walkaround proline and is seeing
those numbers with the 18.5

Its more of a convenience thing for me. Affordable Rec 90 is kind of a pain to deal with in filling her up. The way I see it I should get 3 trips from a tank. My average trip runs a little over 100 nautical so as weight decreases and performance increases I should realize a substantial savings across the board. The way I see it I should gain a full extra trip with every tankful and then some. Looking forward to seeing how it all acts on a real world trip.

I'm not too sure I can compare numbers with the proline. I don't think the deadrise and width factors are the same and the gear and ice load profile of my trips is pretty extreme.

Update: Made it to 20 hours mid way through my last trip. Took about 20 minutes to find in the manual how to turn the alarm off. I was 40 nautical offshore when it flipped and didn't anticipate what I saw on the 10 mile run to my next spot. While cruising along in well spaced 2' seas I took a glance at my fuel burn to notice I went from 2.3 nautical to 2.6 at the same speed I was running prior to the 20 hour mark. I swung it around and proceeded to head back in the opposite direction thinking maybe tide or wind provided the gain but to no avail it was still seeing the improvement. Coming about again I charged on to the next spot varying running speeds seeing the same general .2-.3 improvement in fuel burn.

Being a little technical in nature I knew something didn't just magically happen with the break in of the motor. My only conclusion is that the ECM must change fuel mapping after the break in period and lean up the profile. I am thinking the "lean burn" function of the motor is probably locked out until 20 hours is reached. Anyway, what was already great just got a lot better and may explain what others have seen after break in on theirs.

Props
 

Kmoose,

I've read everything you've posted regarding your boat, the 300 Zuke and your prop selection. Many thanks for your contributions. I have the same boat although a few differences in our restorations. I have a hard top and upper station but my fuel tank is 115 gallons so the net difference in weight may not be that much more.

I am about to order my 300 Suzuki and I am struggling with how to ensure I have the best prop. I hate to spend the money on a new Powertech prop only to find out I should have ordered something else from them. I see you went with the LFS 16 x 18 in a 3-blade but you also said it was a bit "under propped". By under propped, I believe you are saying that you could have used a bit more pitch (18.5 possibly??). Is this correct? If my boat is slightly heavier than yours, I would assume that the 16 x 18 would be just about right. What are your thoughts?

Why did you not go with a 4-blade?

I am going to call Powertech this week and see what they recommend. I am hopeful they can recommend a prop to me once I provide them with the details of my boat.

Here is a pic of my boat. I have the Hermco single bracket.

https://i.imgur.com/lHRqA5p.jpg?1

(I know my trim tabs are too far inboard but I'm gonna let it ride and see if it is manageable before cutting holes in my bracket.)

Sweet boat!! Ken at Prop Gods will allow you to send back and try to get the right one. Cost a few $$$ in shipping but you're not stuck with it unless you damage it.

I believe if you look through Moose's posts he went with a Bravo prop and says the Zuke is "singing a new tune"..........

Great looking boat....Moose has a 4 blade bravo 1. I have the Zuk 18.5 on my Sceptre with DF 300AP. I would start with your 18 or 18.5 with your weight and CG differences (your forward weight will put your chines in the water forward of where Ken's does) . I am transom mounted, but I am barely hitting 5950rpms. Correct prop should produce between 6-6300rpm. EricB also has a tower-but transom mounted also.

I’ll give anyone who wants it a very good deal on the 18 power tech. And yes I’m running a Bravo one but the smallest non custom pitch is 22”. I hit 6000 with a light load but I don’t give max rpm much creadence. The torque curve on a 300 is next to flat from 5800 to 6300 so rpm range is pretty much a weak guide. Best fuel economy at desired cruise speed is the best prop indicator.

2 strokes Vs 4 strokes with VVT and fuel injection. Not the same animals. With 14 years of propping both Yamaha and Zuke 4 stroke outboards I can tell you fuel efficiency at loaded cruise is your primary factor and has no play on engine longevity.

I think we agree that the corect range of rpm will still happen (heavy load at cruise with best fuel efficiency or heavy load getting in the recommended rpm range) either way. Early -detonation was an issue with lugging with 2 strokes...4 strokes are not the same in that area. Running too large of props does still put more pressure on the bottom end on both 2 or 4 strokes - crank, bearings, ect. which creates heat and addition wear and tear. It’s like running a car in 5 gear when it should be in 4th.