Boston Whaler 13 sport
 

I just bought a 2006 Boston Whaler 13' sport with 25HP Mercury 4 stroke. I find it needs a boost to get onto plane. My myself with a full tank of gas it takes 15 seconds to plane out. Without a full tank 10 seconds. If i have a 175LB passenger it takes forever. The passenger has to move far forward before we can get on a plane.

The difference of the weight needed is about 20 pounds. I put a 3 gallon gas container towards the forward seat or back to the helm seating area and that 20 lbs makes a big difference in the time to plane.

This is the advise I have gotten from 5 different marinas. One... Lower the pitch you have with the 3 blade prop by 2". Two... go to a 4 blade prop. Three... install a transom wedge/lift to allow the engine to be 3/4' inboard to the transom. Thereby the lower unit of the engine is at a lower angle like if it was trimmed down. Four... install a Dolfin type wedge on the lower unit. Five.. buy a bigger engine

Have any of you great experienced Winni forum members ever have this problem or maybe know that someone that has? I'm open to any suggestions. Thank you

All those things may help, but they are underpowered with 25 (this HP allows kids to operate them) I believe your boat is rated for 40 HP

underpowered
 

when my kids were young we put 35hp on 13 s with 25 emblems 25hp just dosent cut it

I’d start with the Dolphin wedge.

Same issues with 13-ft Whalers - here are the fixes
 

I've owned/own two 13 ft Whalers (70s/80s versions) with the same problem. Root cause is none of these small Whalers were designed for heavy four-stroke engines sitting on the very very back, they were designed for considerably lighter 2-strokes. The 2006 is a very different boat that my old ones, but sounds like the same problem.

The current boat we have has the 4-stroke 25-hp Merc. It is a dog to plane. IMO 25hp is not enough power for this boat, period, even with shortened pitch prop. I have to trim in aggressively to get it up, then trim out again once on plane.

The first one we had, we replaced the original 1981 2-stroke Johnson 35 with a Nissan 4-stroke 30 hp (same as Merc engines) . That worked well overall power-wise but still needed a 10-inch pitch prop to plane. But: the additional 5 hp power alone was not enough, it still carved a huge hole in the water and took a long time to plane with 2 people.

What is needed is to lift the heavy back end. For both boats, I bought and installed Smart Tabs (passive air spring trim tabs, fairly easy to install) and the tab retraction kit (essential for beaching and trailering). This is the real fix, it aggressively lifts the back end of the boat starting at low speeds. It's a good product, I also use them on a 17-ft 90hp runabout to improve the ride and planing. Install as close to the sides of the boat as you can go to keep the ride flat. You will need to experiment with the angle adjustment to get it right.

In addition, permanently relocate the battery (consider a smaller lighter one, there are options these days) and gas tanks as far forward as possible.

Summary: For 13-ft Whalers to perform well, you will need 30 hp AND Smart tabs to get them on plane in a reasonable amount of time. 25 hp is marginal, but try the Smart Tabs and weight redistribution first see if that is good enough before the more expensive motor trade-up.

Good luck!

SummerIslander...Your response is excellent. Totally agree with you. I will check out the smart tabs. Sounds like the best solution other than putting more weight forward in the anchor locker. I did carry a 2 gallon fuel container and that helped. It didn't take much additional weight to improve performance. Many thanks!

25 hp
 

The 13' Whaler with 25 hp is a nice little package that soesn't requiore certification to operate. Y ou can do some of the teaks suggested above, but it will never be a quick boat if you have a full load. If it takes 15 seconds to plane and you shuffle weight around and get it down to 11-12 seconds, so what? If it is always bow high, then I agree that the trim issues and motor tilt can help. In our case (grand kids have a 13'/25 hp) I never drive, so the major weight always is forward. And, yes, I'm probably too much weight for 25 hp.

I had a late 60’s 13 ft’er with a Yamaha 25 four stroke. It was my island backup that was mostly used to make trash/newspaper runs. I had the same issues that you do exacerbated by the fact that I was running about 245 at the time. It took a while to plane but ran quick & flat once it got there. My final solution (I wasn’t spending a lot of dollars because the boat was never built/intended tone a racer) was to buy and extended fuel hose and put the 5gl fuel tank as far forward as possible. It improved the planing time (still not a sprinter) and allowed me to keep it at 25 hp so the kids could use it without certification.


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I guess the lesson learned is don’t buy until you water test it.

Yes, so true!

Yep always conduct water trials. But when the price is so low giving up the trail makes good sense. There is a solution to the problem and now I have a sweet boat that holds it's value for the kids to use.

Agreed, and the "problem" is not really much of a problem.

Sounds like you got a sweet deal! I'd love to score what you have for the replacement to my son's aluminum, but I'm afraid that ship has left the dock.

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They are great boats. I have a 1987 Super Sport 13. Bought it new in 87 with a 25 hp 2 stroke. Our kids who were then 11 and 8 loved it. I still have it and 5 years ago put on a 25 hp Yamaha 4 stroke. Thought long and hard about increasing the hp but with the grandkids using it decided to keep it at 25.

I have some of the slow to get up on plane issues. Never timed the period to get up on plane but my sense that is not as long as described by chasedawg. We often use it to cruise around our area since it sits mostly uncovered as opposed to the cuddly cruiser with its canvas.

All in all a fantastic boat that has served us well for 34 years.

Sometimes you have to laugh at yourself.

Last year, we sold our 230 Searay and bought a 2020 Whaler Supersport 130 with a 25hp Merc. With a combined age of 152 and a combined weight of 220 lbs, it is the perfect boat for those of us entering our dotage and second childhood.

It planes in about 15 seconds with a top speed of about 23 mph. But it’s very comfortable with the upgraded folding individual seats.

The Lake offers something for everyone at any age.

Power up
 

When the 4 star 40 lower unit blew in 1973 Wadleigh Marine suggested a used 1972 short shaft Evinrude loop charged 50hp. Plenty of power after that!

Update to the solved planing problem
 

Update.... Planning problem solved on our Boston Whaler 13 sport with 25 HP Mercury four stroke. Thanks to SummerIslander his suggestion to try the smart tabs did the trick. It use to take 15 seconds to get out of the hole WOT and onto plane with one person. With two people just about for get it.

Well the results are in. Purchased and installed smart tabs. With one person in the boat now reaches plane at 3000 RPM in 5 seconds. Cruise at half throttle and the boat is just so cool now on plane. It responds so much better. It even takes on tough boat wakes and cruises right through them. No pounding! The bow trim is so much better positioned. The Boston whaler sport is now a totally different and fun boat.

Thanks...SummerIslander I owe you a couple.