How slow is too slow? (long)

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Some of you may have heard this from me before. It is my explanation of why I run slow.
I am simplifying the numbers as fractions are difficult to follow.

We have a number of jumps which are approximately 65 nm. Generally I do these at 6.5 kts, way down from our higher cruise speed of 8kts.

However at 6.5kts we burn two gallons per hour, at 8kts it is close to four gph, almost double.

Thus for a 65 mile trip:

6.5 kts, 10hrs, 20 gallons burned at $6 per gallon (Caribbean prices) $120 US
8 kts, 8 hrs, 32 gallons burned at $6 per gallon, $192 US

Since we will leave at approximately 6 am in all conditions, the difference in arriving at 2 pm, or 4 pm is $72 US, more than enough to buy us dinner.

This may or not be important to all of us, but I consider it a free meal for an extra two hours of watching the world go by.
:thumb:

Exactly the way I cruise and think also....I have been posting the same philosophy on all the "fuel economy" type threads only to be told that fuel costs are meaningless when compared to the other costs of boating...which most of I CANT do much about.

Oh well.....
 
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"can you cruise at 1200 rpm without damaging the engines?"

Usually ,but it depends , simply find a mfg HP chart for that engine and see where the HP curve begins.

Some 1200 (usually industrial) most 1500 , so they can still be used to power 50cps gen sets.

The KEY to long life at low rpm is to load the engine to operate properly at THAT!!! RPM.

Look at that HP graph of your engine and try to prop for at least 50% of the rated power output at THAT listed rpm.

Forget max rated power or max rated rpm, , you are setting up to operate properly at your selected cruise requirement.

Same as you would for a 1200 or 1500rpm rated gen set.
 
Slow cruise 8 knots. Fast Cruise 15 knots. Max speed about 20 knots. Fuel burn at 8 knots so far seems to be about 3.5 to 4 Gph. At 15 knots it seems to be about 16 gph.
Very close to my numbers.

We run the new boat at fast cruise about 20% of the time. Me too.

I can tell you, so far having that extra speed in my pocket when I need it has been wonderful. Given the stage of life we are in now, I am not sure I would even bother owning a boat if I couldn't cover some ground when I need to. Yup, again me too. To our-run weather or for a smoother ride.

Also being able to get the bow out of the water and bang instead of roll (admittedly the Gulfsatr is a very rolly hull) sure makes trips a lot more fun. Agreed. I do however try to avoid rolly conditions.

Are you sacrificing enjoyment of your time on the water to save just a few dollars on fuel?
Probably some are but each to his own.

I think some get a little anal about saving fuel, but I don't condemn them for this. Finding the most efficient way to operate your toy is commendable but if you're not having a good time just to save a few bucs then what's the point.

We left Urbanna for Yorktown on the Chesapeake Monday with forecast seas of 3-4 ft, my max limit. When we got out on the bay it was more like 4-5 ft. We were bobbing around at 7-8 kts like a cork. We were looking at 4 hours of this. Sundeck chairs were sliding from one side to the other. I couldn't take it. We got up on plane to 15-16 knots and things became much more bearable. If we could not plane I would have turned back and waited for more favorable seas. 2 hours later we were in Yorktown, glad the run was over but not puking over the sides either.

2 times last summer we used our higher speed ability to out run thunderstorms. Again glad we had the capability.

Last summer we used 1300 gallons of diesel to get from Tampa to Key West to the mid Chesapeake. That fuel costs half of what it costs to store our boat for a year.

I'm glad I can go fast when I want to and don't worry about the costs. The safety and comfort far out weigh the cost. As mentioned however I do operate at displacements speeds most of the time. Going fast especially when not in open water does require more attention.

But probably the most important issue is keeping my wife happy and comfortable. Being able to plane is a part of that.
 
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However at 6.5kts we burn two gallons per hour, at 8kts it is close to four gph, almost double.

Thus for a 65 mile trip:

6.5 kts, 10hrs, 20 gallons burned at $6 per gallon (Caribbean prices) $120 US
8 kts, 8 hrs, 32 gallons burned at $6 per gallon, $192 US

Since we will leave at approximately 6 am in all conditions, the difference in arriving at 2 pm, or 4 pm is $72 US, more than enough to buy us dinner.

This may or not be important to all of us, but I consider it a free meal for an extra two hours of watching the world go by.
:thumb: Couldn't agree with you more. Leave early; enjoy a leisurely cruising day; save enough money on fuel for a good dinner out!

Ted
 
If people would discuss Nmpg instead of GPh they might get a better view of their fuel use and "savings"
 
We left Urbanna for Yorktown on the Chesapeake Monday with forecast seas of 3-4 ft, my max limit. When we got out on the bay it was more like 4-5 ft. We were bobbing around at 7-8 kts like a cork. We were looking at 4 hours of this. Sundeck chairs were sliding from one side to the other. I couldn't take it. We got up on plane to 15-16 knots and things became much more bearable. If we could not plane I would have turned back and waited for more favorable seas. 2 hours later we were in Yorktown, glad the run was over but not puking over the sides either.

2 times last summer we used our higher speed ability to out run thunderstorms. Again glad we had the capability.

Last summer we used 1300 gallons of diesel to get from Tampa to Key West to the mid Chesapeake. That fuel costs half of what it costs to store our boat for a year.
,,,But probably the most important issue is keeping my wife happy and comfortable. Being able to plane is a part of that.


These are good points, Tim. For exactly the reasons you mentioned, the great majority of boats on our short list were powercats (attempting to get the best of each world in economy and speed). Coming north on the GICW where the channel gets narrow at Boca Grande pass, it was a washtub of wind, current and wakes. Meanwhile, a couple of tennis shoes blew by me, making the situation even more miserable.. I'd have loved to have that speed option then.
 
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If people would discuss Nmpg instead of GPh they might get a better view of their fuel use and "savings"

That's how I look at it, too, Bayview. But when I see 15K at 16GPH, I find myseld doing the calculations in my mind and get a feel that they are using their speed to their advantage while still reaching almost 1 NMPG.

I enjoy my 2.3 NMPG/3.2 GPH at 7.5 kts, but sometime I wish I had the ability to cruise at twice that speed. At WOT, my little Perkins will push me along at 10 Kts, but it's not worth the noise, fuel and risk of failure at that high (2600) RPM.
 
It's completely a personal preference. It's perhaps based on age, stage of life, time available, financial situation, personality, where one has come from, and then factors none of us understand. Some is pace of life and just the way the individual ticks.

Interestingly, forget boats altogether, just think pace of living. Others sometimes think we're living so fast, so much going on so quickly, how can you go at that pace, and the two of us think we're at a relaxed pace, don't feel rushed or hurried at all. We perhaps make decisions and take actions quicker than others might be comfortable. One can't explain an internal clock or the way people are wired differently. As we age we might or might not change. We know others who are so happy and comfortable in their lives doing much less in an average day, week or month than we do. We admire them, we applaud they've found what works for them. They require so little outside stimulation.

I have a hard time doing one thing at a time. That's a strength and a weakness and I fully understand both sides of it. I've had someone comment that my brain never seems to slow down. Well, that's a real problem when it comes to sleep. If I didn't take sleep meds, I'd get nearly no sleep. Before I first started them I was down to 1 1/2 hours per night before I'd wake. Last time I tried without, in three nights combined I slept 1 hour.

We're all different in millions of ways and yet sometimes seem to struggle accepting those differences and even more in truly respecting them. I so admire those different from me. I am in awe of artists as my 6th grade art teacher (her daughters were my swim teachers and I used her pool so it was fine) said I was the worst she'd ever seen. She wasn't exaggerating. I admire those of you who are mechanically inclined and skilled, those who can build things. I'm a danger to myself with just a hammer. Don't dare give me power tools.

The beauty of mankind is the uniqueness of each person.

So, why is it any surprise to any of us that we choose to go different speeds in our boats? Why do some feel it's ok to criticize those who choose differently? We like to occasionally go very slow and take some beautiful scene in, but not for long. Some of it is ever where you came from. On the lake our boat would go 55 knots and we cruised from 35-40. So, even 30 knots is slow by comparison. We chartered an incredible boat once for a week, beautiful in every way, a 113' Burger with WOT of 14 knots and a cruise of 12 knots. We wanted to test ourselves, see if we could be comfortable at those speeds. Surely anyone would love a boat like that. While we could fully appreciate while others did, one week was out limit. We had a great time but we were so tired of going that speed. I know to most of you that seems absurd. We certainly admire those who enjoy 6 knots very much. We can appreciate the beauty and serenity of it. We can appreciate the slow pace. Maybe we'll change over time but for us 15-20 knots is slow. We cruised a couple of days ago at an average 15 knots as we were largely in and out of ports. The following day we had to get in our RIB and open it up. There are times we wish we could enjoy 6 or 8 to 10 knots as many of you do. Another place we aren't understood is that we typically will spend two to three days at a location and then move on and return there again the next trip. Outside of a few major cities we don't stay 5 or 7 days. We feel the need to get to the next place. I know many who will average 7-10 or even 14 days at a location. Even when we're home, after 3 weeks, maximum of 4, we're ready to hit the water again.

We accept ourselves as we are and accept all others as they are. We can intellectually understand fully those who go at different speeds. We just can't feel what they do inside. We all see things in life so differently. We like art, but are not experts in any way. We see something we like or don't. Now we've been to a gallery with a friend as she talked about brush strokes and methods and types of paint they used and all the intricacies that distinguish various artists. We wanted to ask, "Don't you ever just see a painting and just like or dislike it?" I'm sure she couldn't grasp us seeing something at a distance and quickly saying we loved it or we didn't like it. How could we when we hadn't analyzed it?

So, too slow or too fast. Simple. It's when you enjoy it less. Doesn't matter why. If fast is less enjoyable because you're thinking of the money going out or because the wind messes up your hair. If slow is less enjoyable because you feel the need to get somewhere or simply you'd like to feel more wind against your face. None of it matters.

While this forum tends toward the slower group with 85% at least part of the time cruising below 10 knots, still 10% at least part of the time cruise above 20 knots. Is there a closet Fountain owner or fan here somewhere? I don't know. But slow is a predominant leaning here. The only full commonality though is a love of the water and of boating, an appreciation for that special feeling it gives us, for the beauty we see.

Now, I want to hear someone explain all that to a land lover who thinks all boating is silly, a waste of time and money, and doesn't understand anyone who wouldn't prefer to jump in a car or hop a plane. Explain to them why you'd rather take a month or months going from Miami to New York when you can fly it in 3 hours. In reality even those of us who are on the faster side of this group are still moving in the slow lane. If my wife and I want to go from Fort Lauderdale to Miami or West Palm, why is it we'd rather jump in the boat to do it, than drive it? Why have we been to Key West many times but never by car? Why do we frequently go to the Bahamas but the thought of flying there is something that has zero appeal to us?

When you figure human nature out, let us all know.
 
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Good reminder for all of us.
The 103' Burger and Janice' 23' Schuker all share the same tide.
Not to call out Janice, but she seems to be enjoying the lifestyle as much as anyone I ever knew.
 
Good reminder for all of us.
The 103' Burger and Janice' 23' Schuker all share the same tide.
Not to call out Janice, but she seems to be enjoying the lifestyle as much as anyone I ever knew.

Wifey B: It's all the same, only different. :D
 
@BandB. That's a good correlation. Probably why this is the 'Trawler Forum' as opposed to the Fountain Forum. Surround yourself with like minded individuals and you get the same type of opinions (generally).
 
@BandB. That's a good correlation. Probably why this is the 'Trawler Forum' as opposed to the Fountain Forum. Surround yourself with like minded individuals and you get the same type of opinions (generally).

We don't own a trawler and I'm not even going by Marin's definition, just by the general definition, but we enjoy this group of boaters more than others and have more in common when it comes to what we enjoy.
 
If you like (love, enjoy) boating I don't need to explain it (myself) to you.
If you don't, there is no way I can explain it to you.

Ted
 
I am going to start right out by saying that I realize I am treading all over one of this forum's sacred cows in my horrible, greasy, semi planing boots.............

Our new boat. 2005 Mainship 400 T. Twin 240 hp yanmars. Slow cruise 8 knots. Fast Cruise 15 knots. Max speed about 20 knots.............

We run the new boat at fast cruise about 20% of the time. I can tell you, so far having that extra speed in my pocket when I need it has been wonderful.

The trick for me will be disciplining myself to go slow most of the time. So far that hasn't been an issues. I like to troll, and to see the sights. But when it gets rough and rolly, or I need to get home to attend to a work of family matter I don't want to slog along anymore.
I had slow boats for many years and enjoyed the heck out of them & I fully understand why so many on TF have them. After all, the operative word here is TRAWLER!

Since coming back to a faster boat, my enjoyment has increased 3 fold and I am in full agreement with the above quotes. :blush:
 

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Since coming back to a faster boat, my enjoyment has increased 3 fold and I am in full agreement with the above quotes. :blush:

Can you elaborate on why the added speed has increased your enjoyment so much?
 
How slow is too slow?

I don't think "too slow" or "too fast" have definitions that are universally applicable. As BandB commented, everyone's boating objectives are different.

I enjoy going slow--- or not moving at all--- when there is an experience I want to get from doing that. Narrowboating in England is a good example. The speed limit on the canals is about 3mph. Actually, they don't define the limit by speed but by how your wake behaves. If it starts breaking against the canal bank you're going too fast.

Other times the experience I want out of boating is going fast because I enjoy running machinery, the more complex and challenging the better. It's why we will never own anything but two and three engine boats; I find it fun to make all that machinery do what I want it to do.

I also appreciate the notion of going as fast as possible/practical to get somewhere, then putzing about at slow speeds to enjoy the area, and then going fast to minimize the time it takes to get home. This is the reason behind boats like Grand Banks acquiring more and more power over the years as the market for these boats evolved into the "get-there-get-home-fast-but-go-slow-in-the-middle" desires of more and more buyers of these types of boats.

A great example of this philosophy in action in this region are the folks with busy schedules who take one or two week boating vacations in Desolation Sound in boats they keep in Puget Sound.

So I guess the only time slow can be considered too slow is if one has go-fast desires but has a boat that is only capable of going slow. The only solutions to this I can see are buy a faster boat or accept the speed of the boat one already has.
 
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Coming from the sea kayaking world, 7 knots is fast.
 
For me, 6kts is too slow. Just don't like it, but 7+knots I can handle.
 
Some of you may have heard this from me before. It is my explanation of why I run slow.

Thus for a 65 mile trip:

6.5 kts, 10hrs, 20 gallons burned at $6 per gallon (Caribbean prices) $120 US
8 kts, 8 hrs, 32 gallons burned at $6 per gallon, $192 US

Since we will leave at approximately 6 am in all conditions, the difference in arriving at 2 pm, or 4 pm is $72 US, more than enough to buy us dinner.

I thought I was the only one who calculated the cost of going faster in relation to the time saved.

Until my current boat (#13), my prior boats, including a 55' sportfisher, were all go-fast boats and I didn't really care about the cost of fuel burned. It was, in reality, a small part of the total cost of ownership. My current boat was intended for a slightly different mission -- long range fishing: Generally traveling through the night (at 10 knots or less, primarily for safety) to get on the fishing grounds, then spending the day at trolling speeds. At night, either anchor up or or travel to the next destination. There are times when I go fast, for example staying out a little longer in a hot bite then cruising at 18 knots to get to an anchorage before dark, but at least 95% of my hours are at not more than 10 knots. Frankly, I am much happier traveling at displacement speeds, for a bunch of reasons, the least of which is the cost of fuel burned.

However, sometimes one or two of my guests will get restless and suggest that we go faster (usually when they want to get back to dock at noon rather than late afternoon). That is when I pull out a spreadsheet that requires a few simple inputs, one of which is "how much earlier do you want to get in", and it calculates the fuel burn and cost necessary to save that time. Never has anyone been willing to cover that cost (fortunately), and everyone is shocked at how expensive it is to save time.
 
I haven't read every word of this thread but early on but sombody was saying their engine was all warmed up at 170 (or so) degrees. I suspect they were talking about coolant temp and coolant at 180 degrees dosn't mean the engine is warmed up. Lube oil temp of 180 means a warm engine as the engine has made enough heat to bring the oil up to 180 degrees w/o any help from a thermostat to artificially decrease the rate of flow in the heat exchanger that increases the coolant temp.

If you don't have an oil temp gauge check the oil filter w a lazer gun. And a whole bunch of other things while your'e at it.
 
If you don't have an oil temp gauge check the oil filter w a lazer gun. And a whole bunch of other things while your'e at it.

Or you can install an EGT gauge (or gauges if you have multiple engines). Our PNW boat, for example, has an ISSPRO setup, a probe in each exhaust elbow upstream of the water injection and a dual readout gauge. While not quite as informative as individual gauges for each cylinder a single EGT gauge tells you how hard the engine is working. In the aircraft I fly the EGT is used to set the most effective mixture. In the boats they tell us how much work each engine is doing. (Which is what it's doing in the plane, too, but in the plane there's actions one takes with the information.)

The nice thing about them is they react almost instantly to changes in the exhaust temperature. Unlike the engine's coolant temp gauge which thanks to the action of the thermostat can read artificially high and mask what's actually going on inside the cylinders as Eric points out above, the EGT tells you what's going on from the combustion aspect.

So open the throttle and the coolant temperature won't change, or won't change much, because the thermostat simply increases the coolant flow through the heat exchanger. But the EGT will start going up right away because it's measuring the combustion temperature of the engine. The harder the engine works, the higher the cylinder temperatures.

Very handy device, more so in a plane than in a boat, but nevertheless the EGT systems in our boats give us another monitor on the engines' operation.
 
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Perhaps one of my best boating days ever was done with the engine off. I simply let the tide carry me for about 4 miles down a beautiful inlet. It was a wonderful afternoon.
 
Perhaps one of my best boating days ever was done with the engine off. I simply let the tide carry me for about 4 miles down a beautiful inlet. It was a wonderful afternoon.

Sounds like a magical day...and the winner of anyone's fuel efficiency award.
 
Many of you are aware that I travel from Ketchikan to Wrangell to play golf (Close and only course in the immediate area) the distance is 89 km. As 50% of the voyage is in open water (Clarence Straits). The most opportune time to travel this piece of water is early morning.
There is something about departing at 4:AM with hot coffee, good tunes, a humming engine at 12-1300 RPM moving the boat at 6.5 knts in hopefully, calm waters, in the early morning light.
The trip takes 12-13 hours to complete. Even at my age (Hi Sunny!) arriving at 3"PM or so allows for at the least, 9 holes before dark.
The best of all worlds, hours of boating and 9 holes of golf. Life doesn't get much better than that!
Slow is a great go!!:thumb:

Al- Ketchikan
27 foot Marben pocket trawler-'Slo~Belle'
 
Many of you are aware that I travel from Ketchikan to Wrangell to play golf (Close and only course in the immediate area) the distance is 89 km.
Well that's one I've never heard before, taking the boat to go play golf. :thumb:

Ted
 
I know people who take their airplane to another state just to eat a hamburger for lunch and then fly back. Having a destination and a cool story is great. Thats an adventure for the books. Slo cruisin for golfing. I like it !!!
 
I enjoy my 2.3 NMPG/3.2 GPH at 7.5 kts, but sometime I wish I had the ability to cruise at twice that speed. At WOT, my little Perkins will push me along at 10 Kts, but it's not worth the noise, fuel and risk of failure at that high (2600) RPM.


Flywright; It is possible, my 38,000# ACMY got the same Nmpg at that speed but with twin 420 HP Cummins it could also go 23Kts. We mostly cruise at 8-9 Kts but when offshore will run on plane.
 

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