Thanks for the weblink. Looks like good stuff. I'm not committed to diesel only but all things being equal I would definitely lean that way. Safety, convenience and resale all seem to fall diesels way.
Gas vs Diesel
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Many of us sail on a shoestring budget ...
... and must make do w/what we can afford. I'd prefer a diesel, but I wouldn't stay off the water or pass up an otherwise well-found boat cause all I had was an A-4. I raced an A-4 equipped boat for five years on Lake Michigan, in every type of condition imaginable, and a couple times that were unfortunately beyond my imaginings. The engine was tuned and gas lines inspected every spring. The engine never missed a beat. It was totally reliable, used every Wed evening and most weekends. Given the maintenance described above, I wouldn't hesitate to use one. I'd not go to the expense of replacing one w/diesel. One thing I don't recall mentioned here ... the diesels I've sailed usually seem quieter and vibrate less than gas. I find it interesting that some of the people who so loudly protest the safety of gas engines also have propane stoves. I think the key issue is inspection and maintenance. Gas engines and propane stoves are about as safe as your inspection and maintenance protocol. That said, one of these days when I can afford the boat I want, which will probably be later than sooner, I'll have a diesel. Tom Monroe Carlyle Lake
... and must make do w/what we can afford. I'd prefer a diesel, but I wouldn't stay off the water or pass up an otherwise well-found boat cause all I had was an A-4. I raced an A-4 equipped boat for five years on Lake Michigan, in every type of condition imaginable, and a couple times that were unfortunately beyond my imaginings. The engine was tuned and gas lines inspected every spring. The engine never missed a beat. It was totally reliable, used every Wed evening and most weekends. Given the maintenance described above, I wouldn't hesitate to use one. I'd not go to the expense of replacing one w/diesel. One thing I don't recall mentioned here ... the diesels I've sailed usually seem quieter and vibrate less than gas. I find it interesting that some of the people who so loudly protest the safety of gas engines also have propane stoves. I think the key issue is inspection and maintenance. Gas engines and propane stoves are about as safe as your inspection and maintenance protocol. That said, one of these days when I can afford the boat I want, which will probably be later than sooner, I'll have a diesel. Tom Monroe Carlyle Lake
Where are people like MArk getting their "facts"
Just like you quote Mark Twain ""Get the facts first,, ... ...and then you can distort them as you like." So I guess if someone writes something here its FACT. Sorry, but where in the heck did you get this UN-FACT. There is NO TRUTH WHATSOEVER to this statement below. 4) A deisel will require an overhaul after about the same number of run hours as a gas. NOT !! Talk to any Mechanical, Automotive or Desiel Mechanic or Engineer OR look at the amount of hours that are typically logged on a Diesel Engine Vs a Gasoline Engine before an overhaul and you'll have you're answer. You couldn't be more wrong with the above statement and there are lots of reasons for it -- too many to list and detail here. But feel assured that the average gasoline engine will need an overhaul WELL before a diesel engine for many different reasons !
Just like you quote Mark Twain ""Get the facts first,, ... ...and then you can distort them as you like." So I guess if someone writes something here its FACT. Sorry, but where in the heck did you get this UN-FACT. There is NO TRUTH WHATSOEVER to this statement below. 4) A deisel will require an overhaul after about the same number of run hours as a gas. NOT !! Talk to any Mechanical, Automotive or Desiel Mechanic or Engineer OR look at the amount of hours that are typically logged on a Diesel Engine Vs a Gasoline Engine before an overhaul and you'll have you're answer. You couldn't be more wrong with the above statement and there are lots of reasons for it -- too many to list and detail here. But feel assured that the average gasoline engine will need an overhaul WELL before a diesel engine for many different reasons !
Bill from Carlyle IL -- You ask for the numbers
I listed this before but 95% of fuel-related fires were caused by gasoline. Typical problem areas are fuel lines, connections on the engine itself, and leaking fuel tanks. A gas leak has to be taken seriously since it has the potential to explode and destroy a boat – that’s why it’s critical to run the bilge blower for four or five minutes before starting the engine. Remember Diesel is not immune from igniting either – one fire was started when a ruptured line sprayed fuel on a hot manifold. But its much more rare. http://www.boatus.com/seaworthy/fire/default.asp Causes of Fires Started Aboard (Claims only Not in the seriousness of fire) 1)AC and DC wiring/appliance 55% 2) Engine/Transmission Overheat 24% 3) Fuel Leak 8% 4) Miscellaneous 7% 5) Unknown 5% 6) Stove 1% PLEASE NOTE -- I am not advocating anyone from using a gasoline engine - and as I noted before I'd would discount a sailboat I really wanted if it had a gas engine -- i would just have to be more vigilant and cautious with gasoline. But the bottom line is that gasoline is "inherently" more volatile and potentially more dangerous than diesel. It shouldn't be a problem for most people and with any "reasonable maintenance and precautions" it shouldn't be a problem But lets face it -- Diesel is much less dangerous that Gasoline and less likely to cause problems for people out there that are future "Darwin Award candidates". (If you don't know what that means -- forgedaboutit)
I listed this before but 95% of fuel-related fires were caused by gasoline. Typical problem areas are fuel lines, connections on the engine itself, and leaking fuel tanks. A gas leak has to be taken seriously since it has the potential to explode and destroy a boat – that’s why it’s critical to run the bilge blower for four or five minutes before starting the engine. Remember Diesel is not immune from igniting either – one fire was started when a ruptured line sprayed fuel on a hot manifold. But its much more rare. http://www.boatus.com/seaworthy/fire/default.asp Causes of Fires Started Aboard (Claims only Not in the seriousness of fire) 1)AC and DC wiring/appliance 55% 2) Engine/Transmission Overheat 24% 3) Fuel Leak 8% 4) Miscellaneous 7% 5) Unknown 5% 6) Stove 1% PLEASE NOTE -- I am not advocating anyone from using a gasoline engine - and as I noted before I'd would discount a sailboat I really wanted if it had a gas engine -- i would just have to be more vigilant and cautious with gasoline. But the bottom line is that gasoline is "inherently" more volatile and potentially more dangerous than diesel. It shouldn't be a problem for most people and with any "reasonable maintenance and precautions" it shouldn't be a problem But lets face it -- Diesel is much less dangerous that Gasoline and less likely to cause problems for people out there that are future "Darwin Award candidates". (If you don't know what that means -- forgedaboutit)
Numbers
I saw these numbers earlier. Thanks for posting them. The question is whether these numbers relate to sailboats only or all pleasure boats including PWCs, outboards, runabouts, bass bots, etc. If 95% of pleasure boats use gasoline as fuel (probably pretty close when we consider ALL pleasure boats), then its a similar risk as other fuels. There is no question that gasoline has a higher potential for ignition or explosion. But how many time does this occur with sailboat inboards?
I saw these numbers earlier. Thanks for posting them. The question is whether these numbers relate to sailboats only or all pleasure boats including PWCs, outboards, runabouts, bass bots, etc. If 95% of pleasure boats use gasoline as fuel (probably pretty close when we consider ALL pleasure boats), then its a similar risk as other fuels. There is no question that gasoline has a higher potential for ignition or explosion. But how many time does this occur with sailboat inboards?
Appologeez Tom S...
...But I didn't think we were referring to "typical" diesel engine applications. I assumed everyone here was talking about diesel auxiliaries on sailboats. If we were talking 18-wheelers, train engines, generators or even ferries and working power boats or other applications where an engine runs at near optimum RPM for extended periods of time, I too would believe my previous comments indefensible. In fact, some diesels running at constant and continuous low load at 600 to 1,000 RPM have gone as much as 80,000 hours before giving out. But here, we’re talking about something different. We’re talking about an engine that’s run as few as 100 hours per year, mostly in short spurts to and from the slip. It rarely runs long enough to drive all the moisture out of the lube oil or burn the carbon buildup off the cylinder rings. Also, the higher sulfur content of diesel blow-by (even the newer low sulfur blends) forms sulfuric acid mist in the crankcase, which condenses on cool metal surfaces. The corrosion meter keeps running causing pitting on bearing and cylinder surfaces even (and particularly) when the run hours counter stops. Under THESE conditions, the AVERAGE life expectancy of a marine diesel between overhauls is 1,000 to 1,100 hours. (source: David Pascoe, Marine Surveyor) Under these same conditions, the average overhaul interval for gas engines is only about 10% less. (same source). Excuse me for over-dramatizing so little of a difference. "Why shouldn't truth be stranger than fiction? Fiction, after all, has to make sense." -- Mark Twain Happy motoring *_/$), MArk
...But I didn't think we were referring to "typical" diesel engine applications. I assumed everyone here was talking about diesel auxiliaries on sailboats. If we were talking 18-wheelers, train engines, generators or even ferries and working power boats or other applications where an engine runs at near optimum RPM for extended periods of time, I too would believe my previous comments indefensible. In fact, some diesels running at constant and continuous low load at 600 to 1,000 RPM have gone as much as 80,000 hours before giving out. But here, we’re talking about something different. We’re talking about an engine that’s run as few as 100 hours per year, mostly in short spurts to and from the slip. It rarely runs long enough to drive all the moisture out of the lube oil or burn the carbon buildup off the cylinder rings. Also, the higher sulfur content of diesel blow-by (even the newer low sulfur blends) forms sulfuric acid mist in the crankcase, which condenses on cool metal surfaces. The corrosion meter keeps running causing pitting on bearing and cylinder surfaces even (and particularly) when the run hours counter stops. Under THESE conditions, the AVERAGE life expectancy of a marine diesel between overhauls is 1,000 to 1,100 hours. (source: David Pascoe, Marine Surveyor) Under these same conditions, the average overhaul interval for gas engines is only about 10% less. (same source). Excuse me for over-dramatizing so little of a difference. "Why shouldn't truth be stranger than fiction? Fiction, after all, has to make sense." -- Mark Twain Happy motoring *_/$), MArk
1000-1100 hrs between overhauls?
Mark: Maybe we need to take a survey of owners with gas and diesel engines to determine how many hours between overhauls (or complete engine replacements). Yanmar claims 10,000 - 12,000 hrs. is considered a normal life span for a well maintained GM series engine. I have had mine for about 18 years and we are clocking somewhere in the 1400-1500 hr. range and it runs just as well (and also looks) as when it was new. Pascoe's survey's indicate that he is basically a powerboat surveyor, so we are dealing with an entirely different breed of engine. These Yanmar, Kabota, Universal etc. engines are also used in tractors. I doubt they would be selling many of them if they only lasted for 1000 hrs.
Mark: Maybe we need to take a survey of owners with gas and diesel engines to determine how many hours between overhauls (or complete engine replacements). Yanmar claims 10,000 - 12,000 hrs. is considered a normal life span for a well maintained GM series engine. I have had mine for about 18 years and we are clocking somewhere in the 1400-1500 hr. range and it runs just as well (and also looks) as when it was new. Pascoe's survey's indicate that he is basically a powerboat surveyor, so we are dealing with an entirely different breed of engine. These Yanmar, Kabota, Universal etc. engines are also used in tractors. I doubt they would be selling many of them if they only lasted for 1000 hrs.
Congratulations Steve!
Obviously you are doing a fine job of maintaining your engine. Your point about diesel tractors is in agreement with my previous statements. As Bruce would say, diesels are born to run. Farmers tend to run their tractors in excess of 1,000 hours per year and some long-distance haulers do over 2,000, whereas you have only averaged 80 hours per year over 18 years (1,450/18). If Yanmar's claims are true (10,000 hours), your engine will last another 107 years ((10,000/80)-18)?! But that doesn't seem right either, does it? "In the space of one hundred and seventy-six years the Mississippi has shortened itself two hundred and forty-two miles. Therefore ... in the Old Silurian Period the Mississippi River was upward of one million three hundred thousand miles long ... seven hundred and forty-two years from now the Mississippi will be only a mile and three-quarters long. ... There is something fascinating about science. One gets such wholesome returns of conjecture out of such a trifling investment of fact." -- Mark Twain The truth is (way) out there! <o> MArk
Obviously you are doing a fine job of maintaining your engine. Your point about diesel tractors is in agreement with my previous statements. As Bruce would say, diesels are born to run. Farmers tend to run their tractors in excess of 1,000 hours per year and some long-distance haulers do over 2,000, whereas you have only averaged 80 hours per year over 18 years (1,450/18). If Yanmar's claims are true (10,000 hours), your engine will last another 107 years ((10,000/80)-18)?! But that doesn't seem right either, does it? "In the space of one hundred and seventy-six years the Mississippi has shortened itself two hundred and forty-two miles. Therefore ... in the Old Silurian Period the Mississippi River was upward of one million three hundred thousand miles long ... seven hundred and forty-two years from now the Mississippi will be only a mile and three-quarters long. ... There is something fascinating about science. One gets such wholesome returns of conjecture out of such a trifling investment of fact." -- Mark Twain The truth is (way) out there! <o> MArk
A4
Well from a lot of these replies I guess I should be dead or aground. My pearson 30, hull 525 is powered and has been since 1974 by an A4. Common sense and maintainence go a long way I guess. And yes it was rebuilt after 17 years and now is running as well as a new one. Also, when I hit a fast current or tide rip, 30 hp is better than 18.
Well from a lot of these replies I guess I should be dead or aground. My pearson 30, hull 525 is powered and has been since 1974 by an A4. Common sense and maintainence go a long way I guess. And yes it was rebuilt after 17 years and now is running as well as a new one. Also, when I hit a fast current or tide rip, 30 hp is better than 18.
Bill
From the sound of some of the posts, you should donate your boat to be used to mine the harbors of unfriendly countries. When you take the wheel, do you and your crew wear nomex jumpsuits?
(Sorry, I can't find the symbol for "tongue planted FIRMLY in cheek!")
From the sound of some of the posts, you should donate your boat to be used to mine the harbors of unfriendly countries. When you take the wheel, do you and your crew wear nomex jumpsuits?
(Sorry, I can't find the symbol for "tongue planted FIRMLY in cheek!")A4 History
Bill(s), 40,000 Atomic 4's were manufactured from 1947 to 1980 (installed in Catalinas up to 1985). About half are still in service. Does this mean at least 20,000 didn't blow up? History of Universal Motor Company on this link (making marine engines since 1895!): http://www.pearsonvanguard.homestead.com/files/atomic4.htm A4: Out of production for 24 years and most parts are still available. They finally gave in to market/government pressure and switched to selling converted Kubotas in the 1970s. Enjoy, MArk
Bill(s), 40,000 Atomic 4's were manufactured from 1947 to 1980 (installed in Catalinas up to 1985). About half are still in service. Does this mean at least 20,000 didn't blow up? History of Universal Motor Company on this link (making marine engines since 1895!): http://www.pearsonvanguard.homestead.com/files/atomic4.htm A4: Out of production for 24 years and most parts are still available. They finally gave in to market/government pressure and switched to selling converted Kubotas in the 1970s. Enjoy, MArk
MArk I think they gave in to the inevitable and
angry customers like me. P.S. Out of production for 24 years, hmmm. MOST parts still available,, hmmm You know, I bought my 69 Camaro new. It was only produced one year in its' body style. Kinda like the 57 Chev. It's hugger orange, 427cu L88, T400 4:10 12 bolt posi, front and rear spoilers, ducted hood. (ORIGINAL REAL DUCTED HOOD) Even has the original 8 track on the console behind the original console gages. Did I mention the original endura bumper and the Rally Sport option? No? Did I forget to mention its' a Super Sport? The bottom is original paint, no dirt. This is a very small list of stuff on that car. Oh, last month HOTROD Magazine announced the 69 Camaro has joined the 32 Ford as the only two cars in TOTAL reproduction of every original part. IMHO the A4 probably won't make that loftiest of standards. OK, I'm bragging. No, It's not for sale.
angry customers like me. P.S. Out of production for 24 years, hmmm. MOST parts still available,, hmmm You know, I bought my 69 Camaro new. It was only produced one year in its' body style. Kinda like the 57 Chev. It's hugger orange, 427cu L88, T400 4:10 12 bolt posi, front and rear spoilers, ducted hood. (ORIGINAL REAL DUCTED HOOD) Even has the original 8 track on the console behind the original console gages. Did I mention the original endura bumper and the Rally Sport option? No? Did I forget to mention its' a Super Sport? The bottom is original paint, no dirt. This is a very small list of stuff on that car. Oh, last month HOTROD Magazine announced the 69 Camaro has joined the 32 Ford as the only two cars in TOTAL reproduction of every original part. IMHO the A4 probably won't make that loftiest of standards. OK, I'm bragging. No, It's not for sale.
MArk, Steve's comments are "Spot On"
Boy MArk --*o-- I can't believe how "selective" and incomplete your argument is. Without even any good anecdotal stories to bouy your position. Your post is so biased and incomplete I don't really know where to start. David Pascoe is self admittedly mostly refering to High Speed and Planing "Power Boat" Diesel Engines that are light weight and usually turbo charged when he makes those remarks. (Everyone read the COMPLETE story in the links below) NOT typically what you see on AUXILARY SAILBOATS ! -- You seem to have conspicuously left out some VERY important remarks from David Pascoe that totally change everything you said (There we go with those "selective" FACTS again) More of his comments that you seem to have conveniently left out. "There is a direct relationship between service life and the weight of engine blocks and cylinder heads. The heavier, or thicker the castings, the longer they will last" (Like an AUXILARY SAILBOAT ) " Small Boats and Diesel Engines: The question of whether gas or diesel is a better power choice dissolves for boats of a certain size or weight. I draw this line somewhat arbitrarily at around 16,000 lbs or 35 feet. I say "arbitrarily" because a lot of other factors come into play such as hull efficiency and windage in superstructures, but generally speaking you can use these numbers as a general guide line. Diesel becomes the better choice in direct proportion to the amount of weight being propelled. (RE: AUXILARY SAILBOAT ) Internal displacement is the best measure of an engine's ability to deliver power efficiently. And the ratio of CID to horse power (divide CID by engine HP is the simplest measure of how much service life can be expected. The inviolable rule for service life is that the more power is squeezed from an engine block, the shorter it's life span. A 350 CID block generating 260 HP is going to last a whole lot longer than the same block putting out 350 HP, whether its gas or diesel. That's why the old 6-71 Detroit Diesel will run darn near forever at 265 HP from 465 CID, but self-destruct in 6-800 hours at 450 HP. A ratio of 1:2 is about ideal for a marine engine, but at 80% to 90% at least yield reasonable service life. At 1:1 and above it should be considered a high performance engine with a very short service life indeed. " (MARK PLEASE READ THE ABOVE PARARAGH OVER A FEW TIMES --- I THINK YOU MISSED IT !! *o ) Ok lets take a look at some AUXILARY SAILBOAT engine's HP to CID ratio The Catalina 36 with a M35B Universal Engine is 81 CID AND 35 HP looks like an IDEAL LONG LASTING 2+:1 ratio. My Old Watkins 27 with the venerable Yanmar 2QM15 (never did anything but change the oil - 20+ years & 2500+ Hours) CID 41 and HP 15 - ANOTHER IDEAL LONG LASTING 2+:1 ratio. Most AUXILARY DIESEL ENGINES HAVE A 2+:1 ratio of CID TO HP (for example http://www.westerbeke.com/products/diesel_engines.cfm ) Meaning TYPICALLY LONG LIFE !! Once AGAIN MArk VERY TYPICAL OF AN AUXILARY SAILBOAT So it seems your arguments and use of a "few selective" David Pascoes comments are so incomplete to actually be misleading and wrong. PS I have owned and know many many many Diesel engines in Auxilary Sailboat Engines that are 20 + years old & have way more than 2000, 3000, and 4000 hours on it without needing an engine overhaul . For those that want to read David Pascoes COMPLETE analysis and discusion on Diesel Vs Gas engines you can read it here and make your OWN decision and not have it "spun" by anyone here. http://www.yachtsurvey.com/GasDiesel.htm and http://www.yachtsurvey.com/GasNdiesel.htm
Boy MArk --*o-- I can't believe how "selective" and incomplete your argument is. Without even any good anecdotal stories to bouy your position. Your post is so biased and incomplete I don't really know where to start. David Pascoe is self admittedly mostly refering to High Speed and Planing "Power Boat" Diesel Engines that are light weight and usually turbo charged when he makes those remarks. (Everyone read the COMPLETE story in the links below) NOT typically what you see on AUXILARY SAILBOATS ! -- You seem to have conspicuously left out some VERY important remarks from David Pascoe that totally change everything you said (There we go with those "selective" FACTS again) More of his comments that you seem to have conveniently left out. "There is a direct relationship between service life and the weight of engine blocks and cylinder heads. The heavier, or thicker the castings, the longer they will last" (Like an AUXILARY SAILBOAT ) " Small Boats and Diesel Engines: The question of whether gas or diesel is a better power choice dissolves for boats of a certain size or weight. I draw this line somewhat arbitrarily at around 16,000 lbs or 35 feet. I say "arbitrarily" because a lot of other factors come into play such as hull efficiency and windage in superstructures, but generally speaking you can use these numbers as a general guide line. Diesel becomes the better choice in direct proportion to the amount of weight being propelled. (RE: AUXILARY SAILBOAT ) Internal displacement is the best measure of an engine's ability to deliver power efficiently. And the ratio of CID to horse power (divide CID by engine HP is the simplest measure of how much service life can be expected. The inviolable rule for service life is that the more power is squeezed from an engine block, the shorter it's life span. A 350 CID block generating 260 HP is going to last a whole lot longer than the same block putting out 350 HP, whether its gas or diesel. That's why the old 6-71 Detroit Diesel will run darn near forever at 265 HP from 465 CID, but self-destruct in 6-800 hours at 450 HP. A ratio of 1:2 is about ideal for a marine engine, but at 80% to 90% at least yield reasonable service life. At 1:1 and above it should be considered a high performance engine with a very short service life indeed. " (MARK PLEASE READ THE ABOVE PARARAGH OVER A FEW TIMES --- I THINK YOU MISSED IT !! *o ) Ok lets take a look at some AUXILARY SAILBOAT engine's HP to CID ratio The Catalina 36 with a M35B Universal Engine is 81 CID AND 35 HP looks like an IDEAL LONG LASTING 2+:1 ratio. My Old Watkins 27 with the venerable Yanmar 2QM15 (never did anything but change the oil - 20+ years & 2500+ Hours) CID 41 and HP 15 - ANOTHER IDEAL LONG LASTING 2+:1 ratio. Most AUXILARY DIESEL ENGINES HAVE A 2+:1 ratio of CID TO HP (for example http://www.westerbeke.com/products/diesel_engines.cfm ) Meaning TYPICALLY LONG LIFE !! Once AGAIN MArk VERY TYPICAL OF AN AUXILARY SAILBOAT So it seems your arguments and use of a "few selective" David Pascoes comments are so incomplete to actually be misleading and wrong. PS I have owned and know many many many Diesel engines in Auxilary Sailboat Engines that are 20 + years old & have way more than 2000, 3000, and 4000 hours on it without needing an engine overhaul . For those that want to read David Pascoes COMPLETE analysis and discusion on Diesel Vs Gas engines you can read it here and make your OWN decision and not have it "spun" by anyone here. http://www.yachtsurvey.com/GasDiesel.htm and http://www.yachtsurvey.com/GasNdiesel.htm
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