Fuel consumption: sail/motor. are you serious?!

[CaptTom]

Originally Posted by Scrimshaw4

...An efficient, diesel powered power boat should provide about 2 GPM +/- at it's designed cruise speed/RPM...

I agree that GPH figures are unhelpful. But don't you mean MPG? Better still would be Gallons (or Liters) per 100 NM.

I suspect that the reason boaters focus on GPH is a holdover from the days before we had effective ways of measuring speed through the water.

All the old training materials I've seen in various navigation courses talked about leaving point A and setting the engine for a certain RPM, then using the known speed and GPH at that RPM to do your dead reckoning and fuel burn estimates.

Nobody relies on that any more. STW and SOG are displayed right in front of us. We might still set our RPMs where our engine is happiest, but then look elsewhere for distance traveled and fuel burn.

[sailorboy1]

Originally Posted by Chotu

I looked at the trawler equation myself.

there were a lot of 1980s trawlers out there with that old dated interior that were going for $200k-$300k

what about that factor?

You are a terrible shopper! I have been looking there are LOTS of 1980s trawlers in the 48-42' range with low engine hours and good interiors for $100k and less.

[mvweebles]

Originally Posted by CaptTom

Nobody relies on that any more. STW and SOG are displayed right in front of us. We might still set our RPMs where our engine is happiest, but then look elsewhere for distance traveled and fuel burn.

Maybe in some places, but GPH still predominates in the motoryacht/trawler world. Because of currents, sea conditions, no-wake-zones, bridge openings, etc., you may not know how far you've gone in a given increment of time, but most boats have a Hobbs (hour) meter; and they can calculate their fuel consumption at least at fill-up.

I used to be based out of San Francisco and delivered motoryachts and trawlers between Alaska and Mexico. If I relied on owners' fuel-burn estimates, I'd still be floating in the Pacific out of fuel. They are routinely wildly optimistic because most boats make day runs with much of their time spent at low-speed (and very low fuel burn).

My base assumption for a boat 45-60 feet was 10-kts and 10 gph. I would adjust up/down depending on the boat (twins, displacement, etc.). For example, a Nordhavn 57 I delivered SoCal to Ft Lauderdale burned 3000 gals for the 4500 nm trip. 6 gph including generator time. 1.5 miles per gal. But I didn't know that until the first fueling in Acapulco.

[Chotu]

Originally Posted by sailorboy1

You are a terrible shopper! I have been looking there are LOTS of 1980s trawlers in the 48-42' range with low engine hours and good interiors for $100k and less.

They are trash. Junk boats.

[ranger58sb]

Originally Posted by sailorboy1

BTW I went through my records and estimate that if I had a trawler and did 7 knots, got 2 mpg, and diesel averaged $4/gal then the past 7 years it would have cost me about an extra $2k/yr.

So more $$$, but not the hugs amount some, including me, figure

Did you have to replace sails or any of the rigging during that period?

-Chris

[sailingharry]

Originally Posted by CaptTom

I suspect that the reason boaters focus on GPH is a holdover from the days before we had effective ways of measuring speed through the water.

I think it's because it is the only thing we can measure. When my hundred gallon tank is empty, I have put about 100 hours on the hour meter. It would be nearly impossible, most certainly an awful lot of calculations, to figure out how far I motored in that time frame (and really, would require much better record keeping than I do). And diesel fuel flow meters are staggeringly expensive, so very very few people know their instantaneous burn rate to be able to calculate instantaneous MPG.

[OldManMirage]

Originally Posted by Chotu

They are trash. Junk boats.

Here are 3 quick examples of 100K trawlers, 2 under and 1 over. If you are not happy with these there are many more. Now, if this "level" of boat does not suit you, that comes down to a matter of what I would politely call "personal taste." Some people are not happy with tuna and cotton sheets...they require caviar and silk. My point being these are perfectly capable cruisers.

https://jacksonville.craigslist.org/...631218218.html

https://miami.craigslist.org/pbc/boa...625853533.html

https://pensacola.craigslist.org/boa...614898921.html

[OldManMirage]

Originally Posted by ranger58sb

Did you have to replace sails or any of the rigging during that period?

-Chris

This is another aspect of sail vs. power that is often brought up. And it certainly should be considered. On the power side there also has to be factored in the increased maintenance of the engine(s), not just fuel. Even if the sailboat motors 50% of the time, that's 50% less maintenance cost PLUS the fuel. And generally the engines on power boat are larger and costs associated with that are going to be slightly higher too.

Now, to play the flip side, I DO think that the longer the time frame the more the costs even out. And I say that because - as noted above by ranger - at some point you will need to replace the sailing bits on the sailboat. Just ONE new sail goes a long way to balancing out the costs.

As always, the decision often boils down to lifestyle and how you like to cruise.

[sailorboy1]

Originally Posted by ranger58sb

Did you have to replace sails or any of the rigging during that period?

-Chris

yes. that is part of the math

[sailorboy1]

Originally Posted by Chotu

They are trash. Junk boats.

if you say so since you have visited all of them

[sailorboy1]

Originally Posted by OldManMirage

On the power side there also has to be factored in the increased maintenance of the engine(s), not just fuel. Even if the sailboat motors 50% of the time, that's 50% less maintenance cost PLUS the fuel. And generally the engines on power boat are larger and costs associated with that are going to be slightly higher too.

It is hardy anything. In 7 years of cruising full time the direct costs on maintaining my engine are only around $100/yr and I avg 360 hr/yr of motoring time. So even if a trawler is 5x that is $500 and nothing in the big picture

[mvweebles]

In the chart I posted in #26, there are underlying assumptions for setvice each 150 engine hour, not just oil changes. Includes belts, zincs, impellors, filters, etc. Also includes assumptions for engine rebuild, replacement of sails, rigging, etc.

For a 3000 nm year of cruising sustained over 10 years, difference between sail and displacement trawler is just over $2k/year. Not much - around the cost of Starlink.

[Chotu]

Originally Posted by sailorboy1

if you say so since you have visited all of them

Sounds like you have? Do you have some surveys or did you just walk around them?

[Chotu]

Originally Posted by OldManMirage

Here are 3 quick examples of 100K trawlers, 2 under and 1 over. If you are not happy with these there are many more. Now, if this "level" of boat does not suit you, that comes down to a matter of what I would politely call "personal taste." Some people are not happy with tuna and cotton sheets...they require caviar and silk. My point being these are perfectly capable cruisers.

https://jacksonville.craigslist.org/...631218218.html

https://miami.craigslist.org/pbc/boa...625853533.html

https://pensacola.craigslist.org/boa...614898921.html

To cross oceans?

[mvweebles]

Originally Posted by Chotu

To cross oceans?

No. If that's your use case, power options thin considerably even at $250k. Not impossible - there are some one-off or conversions that come up. A very nice Cheoy Lee 46 LRC with stabilizers sold last year for $130k so they come up, but rarely.

But if your intended cruising grounds are North America, Caribbean, and Pacific to Alaska, the list of three posted isn't bad. The Sea Ranger would be my first one to look at. That said, I'm spoiled by hydraulic stabilizers. I wouldn't buy a trawler without them.

As I've mentioned a couple times in this thread. If you want to cross oceans or you're going ultra-cheap, suitable sailboat is considerably less expensive to purchase.