Long lasting gas engines?

Barpilot said:

Wow, I was just cruising some old threads when I ran into this one. Because, like others, I just may want to review some discussions regarding gas vs diesel. We are selling our diesel powered sailboat and moving to a "trawler" (whatever that is). Grand Banks are one of the considerations, but, after reading some of the posts by Marin I might cross GB off my list. I certainly don't want to be involved with a bunch of GB owners with his views or attitude. "A boat like mine" seems to be one of his favorite phrases. Like maybe a boat like his is something to be in awe of.

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Marin said:

Well, you posed and answered the question right there in the most sensible way I've seen yet here.

There IS nothing wrong with gas as a marine powerplant as long as you define what it's good for. Which is, as you say, smaller boats. Or cheaper boats or mass market boats. Gas engines are a really cheap way to power a boat, which means you can bring that boat to market for a whole lot less than you can a boat powered with diesels. The classic albeit overused example of this is Bayliner. The fact gas engines have relatively short lives compared to a diesel is fairly irrelevant for this market because the kinds of boats they're in don't get used all that much, relatively speaking. And if the boat is designed so the engines are under a cockpit where they can be easily swapped out, so much the better.

When you start talking about bigger, heavier boats, boats that represent a considerable investment and so will hopefully have a long life-- 30, 40, or more years---, or boats that are going to run long distances or short distances a whole lot of times for a whole lot of years, then diesels are the best choice, which is why that end of the market--- and the commercial market--- uses diesels virtually exclusively. They woudn't do this if it didn't make economic sense to the buyers and operators.

So both types of engines have their place. But what's being claimed by some here is that gas engines are an ideal powerplant for the upper half of the market. Which, despite their cheap initial cost and cheap replacement cost, does not hold true in my opinon. If it was, Grand Banks and Nordhavn and Fleming and the commercial lobsterboat guys and so on would all be using gas engines.

Engines, other than outboards, are not plug and play devices. Getting the engines in and out of a boat like ours, for example-- or a commercial fishboat---- is a major proposition. Doesn't matter how cheap the engine itself is, the effort to take the old ones out, put the new ones in, and then fix all the stuff you had to take apart or break to get the engines out and in is considerable and expensive. For a boat with an anticipated service life of 30, 40, 50 years or more, it makes no sense to have to undergo that process every few years depending on how much the boat is used.

It makes much more sense with a boat like ours to put one or two engines in the thing when it's built that have a good chance of lasting the life of the boat assuming proper operation and servicing. And the only way to accomplish that is by using a diesel. Which is why companies like American Diesel and Kong and Halverson and others started doing just that back in the 60s and early 70s.

The two different categories of boats are very much apples and oranges, and so need apples and oranges powerplants to make economic sense. Smaller, simpler boat, want to appeal to as large a recreational market as possible, wouldn't make sense to stick anything other than a cheap gas engine in it. Bigger boat, major investment, more complex design, needs to be really cost-effective in the case of a commercial application, it doesn't make sense to stick anything other than a diesel in it.

That's my take on it, anyway.

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Barpilot said:

Any chance at all that you could be just a little more pompous?

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Bp - Pompous may be an understatement for Marin. Very intelligent is too; as is self righteous, sometimes viciously critical of others, and even insightful to the future... these terms and others also could well fit Marin. He and I, as well as he with several TF members, had a fair share of heated post-to-post go-rounds! To some on TF Marin was a virtual Demigod... to others not at all... and, to a few he was simply a BIG PIA. That said, he did post some good stuff, along with some bad. He split from TF when he hit 10,000 posts; then wandered in/out for a while. Guess he still occasionally trolls TF... I haven't noticed him post for a year +/-. Don't be too hard on the ol' boater - We all have our failings! Some members basically pleaded with him to not leave TF (I’m sure he loved that! – LOL). Others said good riddance. I wished him good bye! Marin isn’t really a bad person, just a bit misdirected on a few important counts... but, aren’t most of us all???

Regarding life cycle of gasoline engines / diesel engines: IMO: Life of any motor rests strongly on owner care, maintenance and use schedules/techniques. Engine longevity also is related to builder's design methods, engine model & HP, where manufactured, number of years age... and, many other factors.

All in all, due to product price differences, maintenance costs, and volumes of fuel use differences; diesel - vs - gas engines end up costing just about the same in the long run. There are multitudes of reasons for enjoying one over the other... in boats up to 45' that is. Bigger than that size boat; I believe diesel power far out performs gasoline power due to torque and sheer HP sizes available. You don't hear of gas engines much over 1K HP max. Diesels can be made that go into high fours, five or even six digit numbers of HP. Search archives and you will locate some really heavy-duty thread-discussions for Gas-vs-Diesel.

As to what defines a “Trawler” boat: My take on it – If it floats, is propelled primarily by props (can have mast and sail too), is self contained, can travel fair distances, it’s Ok to stay away from dock for a while, and it has a fair share of sea keeping capabilities – the word “Trawler” could be affixed to it... irrespective of hull design, sizes, layouts, power sources to the props... and other “oh really” items. If asked I prefer to think of our Tolly as a Power Boat Pleasure Cruiser! To some I like to respond: Why it’s a “Thcay”, silly! Finest type of boats in the world. They usually blink twice and simply whisper “OH”... If they’re real nice I let them know it’s yacht spelled backwards. So far – only one got that on their own – lol.

TF Members: If you desire, please write your congress person regarding my simple definition of a Trawler... cause they could care less what really defines a Trawler – just like ME!

Happy Trawler Daze! - Art