markpierce
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Four is better than two!
The single engine thing
- Thread starter Britannia
- Start date
The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.
If you have answers, please help by responding to the unanswered posts.
windmill29130
Guru
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8 is better than 4!
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markpierce
Master and Commander
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Mark as you have read here on YF, singles never break down. Following that logic, two won't ever break down either.
That's very reassuring.
CPseudonym
Moderator Emeritus
Should I just tack this thread onto the back of this thread http://www.trawlerforum.com/forums/s6/single-vs-twin-its-baaaaack-8067.html ?
OP
OP
Britannia
Wannabe
Sorry - I got told in no uncertain terms that I was not allowed to shut it down.
I didn't actually ask or state which was better - not that it made any difference.
Richard
BruceK
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Richard, you couldn`t know where the words "single" and "twin" in one sentence lead. Now leave it alone, it might go back to sleep.
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Well, I had a single engine failure on Saturday morning.
Ok, it was dirtside in my Mercedes ML320 CDI but it was still disconcerting as the engine died completely and without warning halfway across an intersection on a major road. I coasted to the side, largely clear of the intersection. Now I quite like the engine, a common rail V6, but was perplexed as to why it died when it did.
Roadside assistance could not figure out the issue either. The starter would not engage even though the battery tested OK. A jumper pack would not get the starter to turn over, there were no error codes when the guy connected his diagnostic unit. So, it towed to the dealer who needed several hours this morning to find the problem.
It turns out that an Esky I had in the back the day before was not watertight and a bag of ice eventually melted, and the water ran down to the lowest point in the car. That happens to be the battery compartment under the drivers seat. That compartment also houses an electronic control unit. It got wet and shorted.
Now no-one would install a non-waterproof ECU in the bilge of a boat, so what were those damn Germans thinking putting one in the bilge of an SUV?
The good news is that I'll have the car back on the road tomorrow. My daughters will be happy too. They are only just getting organised to manage with one car after the Mazda 3 was totalled in the recent hailstorm, and my commandeering of the Golf for very important trips was tolerated but a little annoying. Oh, and speaking of annoying, the new ECU cost for the ML is $2,700.
Ok, it was dirtside in my Mercedes ML320 CDI but it was still disconcerting as the engine died completely and without warning halfway across an intersection on a major road. I coasted to the side, largely clear of the intersection. Now I quite like the engine, a common rail V6, but was perplexed as to why it died when it did.
Roadside assistance could not figure out the issue either. The starter would not engage even though the battery tested OK. A jumper pack would not get the starter to turn over, there were no error codes when the guy connected his diagnostic unit. So, it towed to the dealer who needed several hours this morning to find the problem.
It turns out that an Esky I had in the back the day before was not watertight and a bag of ice eventually melted, and the water ran down to the lowest point in the car. That happens to be the battery compartment under the drivers seat. That compartment also houses an electronic control unit. It got wet and shorted.
Now no-one would install a non-waterproof ECU in the bilge of a boat, so what were those damn Germans thinking putting one in the bilge of an SUV?
The good news is that I'll have the car back on the road tomorrow. My daughters will be happy too. They are only just getting organised to manage with one car after the Mazda 3 was totalled in the recent hailstorm, and my commandeering of the Golf for very important trips was tolerated but a little annoying. Oh, and speaking of annoying, the new ECU cost for the ML is $2,700.
Tidahapah
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Brian,
Exactly what I was saying about these modern electronic engines.
But I am in the same boat (car) as you, but gotta luv that ML320 electronics or not.
My daughter was in the same situation , her car got written off during that storm in Bris, but they paid her out (agreed value) very quickly and she picked up her new Mazda 3 last week, one happy girl.
Cheers
Benn
Exactly what I was saying about these modern electronic engines.
But I am in the same boat (car) as you, but gotta luv that ML320 electronics or not.
My daughter was in the same situation , her car got written off during that storm in Bris, but they paid her out (agreed value) very quickly and she picked up her new Mazda 3 last week, one happy girl.
Cheers
Benn
Rustybarge
Guru
mark: Indeed the chance of a failure with two engines is greater than with one however the consequences of failure is significantly reduced.
With engines set up to be independent you can shut one down and continue on without interruption. Other than being beside a noisy engine I could do any work on one engine with the other running. Hopefully someone else would be driving the boat and on watch.
With engines set up to be independent you can shut one down and continue on without interruption. Other than being beside a noisy engine I could do any work on one engine with the other running. Hopefully someone else would be driving the boat and on watch.
Marlinmike
Guru
Reliability (twin or single) is a direct result of design, the design for remote cruising would have structure and machinery extremely robust along with full complement of spares the owner could replace in addition keeping a vessel reliable a very comprehensive maintenance plan. Take a good look at Norhavn and you can see it.
RT Firefly
Enigma
Greetings,
The chance of failure of a twin engined vessel is exactly the same as for two single engined vessels and as Mr. bayview so rightly observes, the consequences are MUCH different. To suggest otherwise seems to be based on personal bias.
To re-answer the PO's question "... what do people do when they're single engine breaks down?" Either, wait for assistance or fix the problem in place given the spares, tools and abilities of the people on board. Case closed.
The chance of failure of a twin engined vessel is exactly the same as for two single engined vessels and as Mr. bayview so rightly observes, the consequences are MUCH different. To suggest otherwise seems to be based on personal bias.
To re-answer the PO's question "... what do people do when they're single engine breaks down?" Either, wait for assistance or fix the problem in place given the spares, tools and abilities of the people on board. Case closed.
Wxx3
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Richard,
Having read all of the above, I hope what you take from it is that's there is no right or wrong.
Find the boat that works for you; in most cases, that alone will make the decision for you.
RT Firefly
Enigma
+1
It's real!
Drug runner, English Channel.
Think you'd need those drugs before you open the throttles.
Ted:lol:
Assuming you are referring to JUST the engines, then - theoretically - yes.
But in the real world, off-side maintenance on twins suffers from accessibility. Out of sight, out of mind may apply - if not to you, then to the POs. It's easy (on my boat) to get all around the engine with an IR thermometer while running - I cannot imagine a twin owner attempting that. Off-side coolant leaks? Oil leaks? Corrosion? Any type of connection at all? Definitely not equivalent to single.
And then we get into maintenance costs. Some folks here do everything "by the book", others are on a budget - or their POs were on budgets.
And that's just the engines themselves. Running gear...there is truly no comparison to a single keel-protected prop.
And then there's the real world maneuverability of a twin with small rudders running with one engine.
Honestly, I (personally) wouldn't be more confident with twin engines - and suspect that they may bring a false confidence to the less experienced.
Rustybarge
Guru
There's an old saying amongst pilots concerning twin engined planes: the second engine will bring you to the scene of the accident!
Admittedly a twin engined planes try to turn turtle when one engine fails.
RT Firefly
Enigma
Greetings,
Mr. ref. Yes, I was referring to JUST the engines. You DO make valid points regarding maintenance and accessibility outboard of twins but as to failure rate for JUST the engines, the same, as ANY engines reliability is maintenance based.
Mr. ref. Yes, I was referring to JUST the engines. You DO make valid points regarding maintenance and accessibility outboard of twins but as to failure rate for JUST the engines, the same, as ANY engines reliability is maintenance based.
While this is purely anecdotal, we know more single engine boaters (including sail) who have fouled or damaged their one prop or rudder than we know twin engine boaters who've fouled or damaged one of their props, struts, or rudders.
What this perhaps tells me is that the operators of twins are more vigillant at the helm knowing the potential vulnerability of their running gear, and the owners of singles rely too much on the theory of keel protection of their running gear to the point where the reality of running a boat in waters containing debris, pot lines, etc. bites them in the ass.
psneeld
Guru
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.
I often shove my Shamrock keel drive up on a sand/mudbank to get to a grounded vessel...and when backing off with a towline the boat gets pulled around and shoved into a sand shelf that ultimately stalls the engine in some cases. I seriously doubt a twin would last all summer with that abuse without repetitive repairs.
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.
I often shove my Shamrock keel drive up on a sand/mudbank to get to a grounded vessel...and when backing off with a towline the boat gets pulled around and shoved into a sand shelf that ultimately stalls the engine in some cases. I seriously doubt a twin would last all summer with that abuse without repetitive repairs.
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One of the nice design features of twin-engine Grand Banks boats is that the keel is lower by a fair amount than the props and rudders. Also, if the boat should go around and a falling tide let it tip to the side to rest on the keel and chine, the prop, struts, shaft and rudder on the low side wil be tucked up inside the "triangle" formed by the keel, hull, and bottom and so will not touch the ground (assuming a smooth-ish surface under the boat). This is due to the running gear of GB twins being fairly close in to the centerline.
Age of the boat should be a consideration. I have done deliveries of a few Nordhavn's, one from Key West to Virginia and felt comfortable offshore on a 5 year old single engine boat. However I would be concerned running a 15 to 25 year old single or twin boat in an area where inlets are few and far between. Many failures have nothing to do with the internal parts of the engines but with steering, transmissions, cooling, fitting on the engine and more. It may not be lack of maintenance but simple metal fatigue.
psneeld
Guru
How true...
Had a delivery once and didn't make it from the slip to the fuel dock 200 feet away without both engines overheating.
Then I got the truth about the history of the boat from the locals.....on the hard for 3 years with no one around to do anything....not what I was told/
The impellers had turned to dust.
So without an accurate history of maintenance and treatment...all boats can be a crapshoot.
