With the continually escalating price of fuel, this topic becomes even more relevant. No matter where we turn, someone is telling us that we are getting fat and need to be thinner! Look at a previous post concerning the USCG increasing its figure for how much an average ferry and excursion boat passenger weighs as a result of the majority of American’s bulging waistlines.
Our boats are also getting heavier! As boats get older, they get heavier and that has a lot to do about being less “sea-kindly” and more “tender” as they get older (and our reflexes get slower – not a particularly good combination.) With fuel getting more expensive, here are some examples of how the boat is getting heavier – and more expensive to operate.
We add things to our boat that weren’t there when we bought it. An ice chest may be added so we don’t have to lug one from the car. We add an additional ice chest so we can bring more ice so we can stay out longer and catch more fish (hopefully!). We pile up the cuddy cabin, a.k.a., the boat’s attic, with safety and fishing equipment so we don’t have to lug them from the car.
And don’t forget that new 4-stroke engine you added – so much quieter, so much more fuel efficient and so much heavier per “horse of power”… at least an estimated 20% heavier. That makes a 400lb 200hp 2-stroke weigh in at nearly 500lbs as a 4-stroke state-of-the-art power plant.
Boats Get “Wrinkles” too
Through tiny cracks in the gel coat, water seeps inside the hull and the boat gets 8 lbs heavier per gallon and it seeps, generally, aft where the boat is naturally heavier per square foot of hull due to the engine making it harder to see over the bow when you gun the engine and start to “dig the hole” that getting up on plane gets you out of. This makes it harder to get on plane, i.e., you have to go faster, to get up on plane since the boat is heavier in the stern than when it was manufactured thereby using more fuel. It is becomes an endless spiral.
What to do about it? There are only 2 or 3 things that you can do. First, get rid of anything that isn’t essential. How much of a big deal is it to cart just the things you need – not everything you own all the time – from the car or the dock locker that you installed at the foot of your slip? Second, you may want to look into trim tabs – small “flaps” that are installed under your transom that will help you get up onto plane faster. What they save in fuel when “digging out of the hole” will quickly cover their costs. And don’t underestimate the safety factor that you’ll be able to see over the bow sooner. Third, you may need to change your prop! The engine may be plenty powerful enough to move your mini-warehouse but it can’t turn the propeller any faster due to its pitch (angle that it cuts through the water.) Counter-intuitively, you need a smaller prop/tighter pitch, not a larger one, to enable the engine to rotate the shaft more rapidly. Think about the little tires on your trailer keeping pace with the big tires on your truck – they HAVE to move faster to keep pace. Talk to your dock master about who he or she uses when they re-engineer props for customers. Go see them and talk about your options. This is some art, some science and some superstition. Talk it through with people who make a living engineering propellers. It will make a difference.