The single engine thing

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Based on my 12 years of assistance towing...twins pulled off sand bars regularly require towing for repairs...the singles with full keels rarely do.

At least where going aground for most is at least an annual event, if not mothly, weekly or every outing event ...for some.

There's more to it than theory....but just because you own a twin doesn't mean you would have suffered any more damage than owning singles your whole life... depends on where and how you boat.

But without any doubt in my mind, singles with full keel protection (not all have it) are less likely to occur damage in many situations where a twin would....everything equal.

One of the factors we took into account before our purchase, knowing that with adventure and going off track, comes groundings and other inadvertent shenanigans.

You guys saw the picture of my prop:eek:

I'm pleased to say that I haven't been aground in at least 3,000 nm, but who's counting.
 
With arguably the best maintenance in the world and the best operators on the planet, Transport Category aircraft are required to have a minimum of two engines to meet the regulatory failure analysis requirement. Anyone interested in putting their family aboard a single engine 777?
 
With arguably the best maintenance in the world and the best operators on the planet, Transport Category aircraft are required to have a minimum of two engines to meet the regulatory failure analysis requirement. Anyone interested in putting their family aboard a single engine 777?

As I recall, it took decades for the regulators to allow twins instead of four engines!!
 
As I recall, it took decades for the regulators to allow twins instead of four engines!!

True, although the reason had more to do with the huge excess thrust capability and efficiency of modern high bypass turbofans than the reliability issue.
 
With arguably the best maintenance in the world and the best operators on the planet, Transport Category aircraft are required to have a minimum of two engines to meet the regulatory failure analysis requirement. Anyone interested in putting their family aboard a single engine 777?

What about all those people driving around in single engine cars?

Yours is not quite an apples to apples comparison - I'd far rather be in a boat that has lost power than in a 777 that has lost power.

Richard
 
What about all those people driving around in single engine cars?

Yours is not quite an apples to apples comparison - I'd far rather be in a boat that has lost power than in a 777 that has lost power.

Richard

Yes, a bit of hyperbole. Lots of single engine general aviation aircraft as well. Just making the case that there is unquestionably less risk with redundant systems. At how much risk are you willing to expose your loved ones.
 
Yes, a bit of hyperbole. Lots of single engine general aviation aircraft as well. Just making the case that there is unquestionably less risk with redundant systems. At how much risk are you willing to expose your loved ones.

I understand the literary style ;-)

But in practice, how much risk are we really talking about? How many lives are lost as a result of single engine failure in a trawler? How much safer are your loved ones driving down the freeway? I wonder which has a higher fatality rate per hour?

Richard
 
One of the factors we took into account before our purchase, knowing that with adventure and going off track, comes groundings and other inadvertent shenanigans.

You guys saw the picture of my prop:eek:

I'm pleased to say that I haven't been aground in at least 3,000 nm, but who's counting.


Running aground is quite common for those who boat on rivers, happened to us several times when living near St Louis. And many others too. On larger vessels there, twins are the combination of choice because one can't get anywhere at 7 knots.

We as did others, became quite adept at not damaging props and underwater things attached to the boat. The real damage was done by drunks at planing speeds straying off course. My many low speed excursions onto the sand and soft mud never hurt the gear but filled the strainers with crap that had to be cleaned out. Heck we intentionally pulled our twin engine vessels onto the sand bars to party.

As the years went on and rocky sea water bottoms became the norm, so did caution and getting a twin engine vessel whose keel is about 14" below the props. Yes I'd dearly love to have a big single like Delfin or Twisted. But these singles along with Selenes, NT and AT are very expensive. Twins in the 50' range are much more prolific and many less $$100K than the aforementioned.

So for us, twins are an economic decision - way cheaper and with a larger buyer's pool than the similar sized singles we lust after. The singles in the +50' range we have pursued all have get homes, that is what the buyers of these types of vessels desire too.

And Richard, some of us have many more miles on our twins than single engine owners would ever contemplate and have never run big time aground. Why should we, it could damage the active stabilizers. :thumb:
 
I understand the literary style ;-)

But in practice, how much risk are we really talking about? How many lives are lost as a result of single engine failure in a trawler? How much safer are your loved ones driving down the freeway? I wonder which has a higher fatality rate per hour?

Richard

Back to apples and oranges. Each operating environment is it's own subset. Also, redundant power systems are not as readily available in the automotive world. In the current used boat market place single engine boats are often priced higher than twins in the same hull. Why? Because buyer/operators place fuel economy and operating costs above safety.
 
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Back to apples and oranges. Each operating environment is it's own subset. Also, redundant power systems are not as readily available in the automotive world. In the current used boat market place single engine boats are often priced higher than twins in the same hull. Why? Because buyer/operators place fuel economy and operating costs above safety.

I'm not sure I made myself clear. I was referring to the overall risk of driving a car on the freeway - the risk of death by accident not engine failure. I was trying to make the point that the chances of death or injury to people on single engine trawlers as a result of engine failure is likely very low compared to other risks they face in daily life. In an absolute sense the risk isn't that high.

Having started this thread and read all the comments I can say that I am open to a single engine boat with no get-home if the right one becomes available.

Richard
 
Having started this thread and read all the comments I can say that I am open to a single engine boat with no get-home if the right one becomes available.

What would be the right one? Have you done any serious looking, made offers, gone to survey etc. Or just made TF owners happy by getting lots of hits, it is a business you know.

A few years ago on The Hull Truth, one of the participants with over 6,000 posts was outed as a hit maker. Tis the way the world works today.
 
What would be the right one? Have you done any serious looking, made offers, gone to survey etc. Or just made TF owners happy by getting lots of hits, it is a business you know.

A few years ago on The Hull Truth, one of the participants with over 6,000 posts was outed as a hit maker. Tis the way the world works today.

A Krogen 54 Pilothouse might be the "right one".

I have made two offers. Both twin engines, non stabilized. Neither made it to survey. I'm disappointed that you question my motives - while there may be a few scammers out there most of us are honest and up front.

Richard
 
A Krogen 54 Pilothouse might be the "right one".



I have made two offers. Both twin engines, non stabilized. Neither made it to survey.

I have cruised for a few weeks on a friend's Krogen 54 along the coasts of Maine and Mexico. That pilothouse (let alone flying bridge!) is quite a ways off the water and the couple of (brief) moments where we switched off the stabilizers (Naids, I think) were quickly uncomfortable.
 
I have cruised for a few weeks on a friend's Krogen 54 along the coasts of Maine and Mexico. That pilothouse (let alone flying bridge!) is quite a ways off the water and the couple of (brief) moments where we switched off the stabilizers (Naids, I think) were quickly uncomfortable.

Yes - I can see that the height off the water would be a big factor. I'm pretty much set on getting a boat with stabilizers at this point. Interestingly though, another owner of an unstabilized Krogen 54 told me that it wasn't too bad without them. My experience with my sailboat is that there are often points of sail that are quite uncomfortable. I usually change tack a bit to improve things.

Richard
 
What would be the right one? Have you done any serious looking, made offers, gone to survey etc. Or just made TF owners happy by getting lots of hits, it is a business you know.

A few years ago on The Hull Truth, one of the participants with over 6,000 posts was outed as a hit maker. Tis the way the world works today.



This is a forum for the exchange of boat related information. Why d you have to be boat owner?
 
As I recall, it took decades for the regulators to allow twins instead of four engines!!

No, it didn't. ETOPS (Extended Twin Engine Operations) was enacted relatively quickly in the mid-1980s. Both Boeing and Airbus worked with the regulators to get ETOPS approval for the 767 and A330 initially. The time limits were gradually extended as twin-engine reliability generated more data.

And four engines was not previous requirement. Three engines were also acceptable for long-range, over-water operations prior to ETOPS. Hence the DC-10/MD-11 and L1011.

Once the 767 and A330 set the precedent, ETOPS approval for other models quickly followed. The 777 was ETOPS-approved from the day it went into service. The 737 obtained ETOPS approval and operators like Aloha Airlines began using them between the US west coast and Hawaii in the late 1990s. I produced a lot of videos supporting our and the airlines' ETOPS efforts, and later produced videos about Aloha's Oakland-Honolulu 737 operations when they first began.
 
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One engine/two engine the debate continues. To me it is all about peace of mind. That is why I have two engines, two VHFs, two handheld VHFs, Epirb, Lifevests, Dingy with motor, flares, first aid kit, TowBoat US, spare parts out the yingyang and I know I'm leaving something out. If one engine falls, I have the other. If the second fails, I'm calling for a Tow. If I'm out a reach of a tow, I'm calling out for help on the radio. I will continue to use any and all means necessary to fix the problem or get help. One engine guys, just have one less step than I do and probably a fatter wallet! ;)
 
Windmill, you seem to have addressed your insecurities. :thumb:
 
Think I'll have another heart transplanted into my chest, as it appears obvious that having just one will never do :D
 
I agree on the fatter wallet I could not afford twins. Marine parts can eat you out of a boating season in a hurry. If you truly plan on going where no else every goes or lives why are you going there in the first place? Most locations you might tow a local or they will tow you. The more remote usually the more friendly people are. Good luck on finding a boat and run it about 500 hrs. If you are still running you will have work most the problems out. The least will be the motor or motors I bet.
 
In the 16 years we've owned our twin engine boat we've not found the operating cost to be much higher--- or in some cases any higher--- than the costs acquaintences have with single engine boats. For the most part, you buy twice as much lube oil and two times the number of oil and fuel filters. Compared to the overall cost of owning a boat, lube oil and filters are free.

Fuel burn is not twice that of a single, assuming the same type of engine in the same type of boat. We run our two engines at 1650 rpm to get 8 knots. People we know with the single engine version of the same boat we have run their engine at 2,000 rpm to get 8 knots. And their one engine is working harder than each of our two engines. So as near as rough calculations can figure, we burn perhaps 1.5 times as much fuel as the single-engine owners (of the same boat). In the overall cost of owning a boat, that difference is irrelevant.

While we have occasionally had to replace ancilliary components on our engines--- oil and transmission heat exchangers, the water pump belt, a pinholed fuel injection pipe--- these never occurred at the same time on both engines. So compared to the overall cost of owning a boat, the occasional additional parts required were an insignificant cost.

There were three times when having two engines resulted in a cost that was significantly higher than if we'd had just one. One was when we had the exhaust systems that were on the boat when we bought it replaced with new, custom-made fiberglass systems. One was when we had the motor mounts on both engines replaced, a once-every-thirty-years-expense, and once was when we had both raw water pumps replaced with new, one-piece pumps (we went ahead and changed both engines even though only one actually had a problem with its pump drive coupler).

So while it's true that over time, two engines will cost more than one in terms of maintenance and repair, this extra cost will be spread out over so many years that it is insignificant.

And.... our "spare" engine under the floor has prevented us from having to come home on the end of a very expensive rope four times. What we didn't have to spend on tows--- a couple of which would have been very long ones and extemely inconvenient--- probably more than made up for whatever running two engines vs one costs us.

And.... we have friends with single engine boats who have had to spend far more repairing their single-engine setup, plus towing costs, than we have spent on our two engines.

So based on our 16 years of experience with a twin-engine boat, we don't buy the "costs twice as much" theory at all. It certainly CAN cost twice as much depending on the condition of the engines and drive trains and how the boat is operated and maintained. But it's not an automatic given.
 
If cost of ownership is the main concern then hands down go single engine. In my experience we had to replace one of our engines to the tune of 25G. So our twin did cost us a bunch more, but what if we were a single engine and that engine failed? Would we not be in the same boat then cost wise, pun intended?
 
twin vs. single

I have read a few articles about this. The one point I remember and think it to be true. Usually, if you loose an engine it's a fuel thing. SO.....you will probably loose both. I can't say, because I have always had a single engine. I choose to keep my engine well maintained. The times I got in trouble was fuel or the impeller. One time I ran out of fuel! That was embarrassing. Boat US Tow came with 5 gallons of fuel. I had to bleed the engine and that was that. One time I got some bad fuel, I changed the both filters and managed to get home. I had the fuel polished. The impeller is self explanatory. That's why I like diesel engines. You keep the fuel clean and enough air and it will usually be running. In 25 years, I had to get towed off the bottom a few times (in my sail boat days), but the times I needed to be towed I was glad Boat US Tow was there.
 
I promise I'm not a troller in the trawler forum. I understand that the single vs twin engine (or get home) is a quasi-religious question. However, it's going to factor into my decision and I'd love some input.

So here's my question - and it's not "which is better?" Rather, what do people do when they're single engine breaks down? Here are some options that come to my mind

1) Call for a tow home - this is ok if you're in range of a tow company. I have had the BoatUS Gold Towing service for over a decade and wouldn't be without it

[Let's assume you're making a coastal passage and not in tow boat range]

2) Fix the engine. The most likely things to stop a well maintained cruising engine can be fixed by the well-prepared skipper who has spares (fuel filters, pumps, hoses, impellers, etc)

3) Is there a number 3?

It's a serious concern for me - since I intend on making coastal passages and expect to be out of tow boat range. However, if people do this without undue risk then I'd like to be able to consider single engine boats.

Thanks

Richard

Above is the original post/question for this thread.

It's amazing how we can't resist diving into the single vs twin debate, even when the original post asked that we set that aside and only address the questions of "what do you do when your single engine dies", which I think is a really good question.

So, in an effort to distract us away from further single/dual temptation, and considering that we have an anchor debate already going.....

What micron fuel filters do you use, and why? There, that should distract us for a while...:popcorn:
 
I have read a few articles about this. The one point I remember and think it to be true. Usually, if you loose an engine it's a fuel thing. .

Quite simply a self perpetuating myth. Unless of course:
  • You fill up routinely in the Bahamas or Mexico,
  • have dirty 30+ year old tanks or
  • a deck leak in the around the filling apparatus :eek:.
In the half dozen or so times I've had an engine become balky or dead weight it was never fuel. Years ago when a youngster and worked in the boat repair business ditto, hardly ever bad fuel.

The worst recent engine experience I personally ever had was when a diesel engine became recalcitrant and I called the dealer. FUEL, it has to be water in the FUEL! It can't be the engine! Over and over again and sending me in wrong directions as to real problem and solution.

Those who sell polishing systems, magnets, additives and write articles on the virtues of product line will thump drum saying the "bad fuel is the Number 1 cause of diesel engine shutdowns." Just advertising BS like LSMFT (remember that one?) or put a tiger in your tank.

When supposed gurus like A, B and C state the same just be cynical and say "really." There may some consulting/shill money hidden there.
 
What micron fuel filters do you use, and why? There, that should distract us for a while...:popcorn:

If I was lucky enough to have a Tier III common rail like some - 30u, 10u and on engine (Fleetguards) and not a Racor. And a high volume polishing system and day tank like some more fortunate are so vessel equipped. And then of course a really good get home system :smitten:
 
In the 16 years we've owned our twin engine boat we've not found the operating cost to be much higher--- or in some cases any higher--- than the costs acquaintences have with single engine boats. For the most part, you buy twice as much lube oil and two times the number of oil and fuel filters. Compared to the overall cost of owning a boat, lube oil and filters are free.

Fuel burn is not twice that of a single, assuming the same type of engine in the same type of boat. We run our two engines at 1650 rpm to get 8 knots. People we know with the single engine version of the same boat we have run their engine at 2,000 rpm to get 8 knots. And their one engine is working harder than each of our two engines. So as near as rough calculations can figure, we burn perhaps 1.5 times as much fuel as the single-engine owners (of the same boat). In the overall cost of owning a boat, that difference is irrelevant.

While we have occasionally had to replace ancilliary components on our engines--- oil and transmission heat exchangers, the water pump belt, a pinholed fuel injection pipe--- these never occurred at the same time on both engines. So compared to the overall cost of owning a boat, the occasional additional parts required were an insignificant cost.

There were three times when having two engines resulted in a cost that was significantly higher than if we'd had just one. One was when we had the exhaust systems that were on the boat when we bought it replaced with new, custom-made fiberglass systems. One was when we had the motor mounts on both engines replaced, a once-every-thirty-years-expense, and once was when we had both raw water pumps replaced with new, one-piece pumps (we went ahead and changed both engines even though only one actually had a problem with its pump drive coupler).

So while it's true that over time, two engines will cost more than one in terms of maintenance and repair, this extra cost will be spread out over so many years that it is insignificant.

And.... our "spare" engine under the floor has prevented us from having to come home on the end of a very expensive rope four times. What we didn't have to spend on tows--- a couple of which would have been very long ones and extemely inconvenient--- probably more than made up for whatever running two engines vs one costs us.

And.... we have friends with single engine boats who have had to spend far more repairing their single-engine setup, plus towing costs, than we have spent on our two engines.

So based on our 16 years of experience with a twin-engine boat, we don't buy the "costs twice as much" theory at all. It certainly CAN cost twice as much depending on the condition of the engines and drive trains and how the boat is operated and maintained. But it's not an automatic given.


Agree to Marin, at least with regard to costs for operations and normal maintenance.
(O.k. you should not ask me when I just finished oil and filters on the first FL but only 50% of the work done)

Fuel burn:
Can even be less with twins, depending on the speed range you are interested in.
If we run the 8 knots which is our hull speed (and what is above our normal "Marschfahrt" -sorry, missing the English word) we run our twin FL120 at ~1700/1750 rpm, burning 2 liters per nautical mile. Same boat, single FL120, runs above 2200 rpm, fuel consumption more than 10% above ours.
Slowing down to 7 knots (~ 1400 rpm w twins / ~ 1650 rpm w single) the single version burns 10% less fuel...

However we normally cruise in a speed range where a single engine would have an advantage in fuel consumption. But we appreciate the plus in "getting home ability" which comes with the twins.
And I guess who ever tried to fix even a nuisance issue in the machine room of a small boat dancing in high swell will do the same...

All valid as long as it doesn't come to major repairs - let's cross fingers!


best regards / med venlig hilsen
wadden
 
... getting home ability:
We should not focus on the what if engine failed question only.
Please consider in addition the plus in power and maneuverability which might be very helpful if out there it has become worse than expected.



best regards / med venlig hilsen
wadden
 
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