After 10+ great years with a 330DA I am looking to move up to a 400DA. Two boats of interest local to me (Canada ... although certainly will look at fresh water US) ... one diesel the other gas. about $20K price difference. I was told by a broker that fuel usage per hour is similar for both and that the diesel will simply run a bit faster on the water so there is a marginal economic gain??? Any enlightenment from this group would be helpful.
Sundancer 400DA - diesel vs gas?
- Thread starter BVasily
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I think your broker gave you a "quick and dirty" bit of info. Suggest you refine your question and do some additional research. Longevity of diesel vs gas, Hours that you will use per year, availability of qualified maintenance near your homeport, documented maintenance history of boats..these are what I'd be looking at in trying to sort out otherwise similar boats.
Let me guess; the guy who told you that is selling the gas boat.
BS gas will use more fuel to make the same HP though neither will go very far on a gallon of fuel. If everything is equal, which it never is, the diesel boat is the one to get unless you rarely go far. So consider how you will use the boat first, for short slow trips fuel cost doesn't matter.
the final price will be determined by which seller is more eager not by the engines.
BS gas will use more fuel to make the same HP though neither will go very far on a gallon of fuel. If everything is equal, which it never is, the diesel boat is the one to get unless you rarely go far. So consider how you will use the boat first, for short slow trips fuel cost doesn't matter.
the final price will be determined by which seller is more eager not by the engines.
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BS... The broker is either clueless or a liar. Diesel has more energy per gallon than gas to a Diesel engine will always use quite a bit less fuel to make the same amount of power. Try to find some boat test results on line for this boat, or similar boats to compare. When y get to to 40' or 20k lbs, ga are starting to run out of torque...
Now, fuel consumption alone isn't the only factor. The diesels should last longer before they need a rebuilt (note that I said "should" not "will") but the rebuild will cost you a lot more. $20k for a 6 cyl engine is probably a good number to plan on by the time you re all done.
It all comes down to how many hours you will use the boat... Up north in your frozen wastelands you probably will not put enough hours per year to make it a clear cut case favoring the diesels
although to many people the safety of diesel is worth the extra $
But again to answer your question, diesel use a lot less fuel than gas
Now, fuel consumption alone isn't the only factor. The diesels should last longer before they need a rebuilt (note that I said "should" not "will") but the rebuild will cost you a lot more. $20k for a 6 cyl engine is probably a good number to plan on by the time you re all done.
It all comes down to how many hours you will use the boat... Up north in your frozen wastelands you probably will not put enough hours per year to make it a clear cut case favoring the diesels
although to many people the safety of diesel is worth the extra $But again to answer your question, diesel use a lot less fuel than gas
Most important thing is the condition of the boats and engines and that they have not been abused - over propped or under serviced.
Having said that we cruise with a bunch of Sea Rays and 4 are very similar with 2 being diesel and 2 big block gas. A 37 gas, two 38's one gas one diesel and a 40 diesel. Over a number of seasons often cruising the same routs at the same speeds we have seen and discussed the differences especially with the two 38's.
At about 1,000 nautical miles per year / about 80 engine hours / about 50 engine hours
at cruise and 60-80 genset hours the gas boats get approx. 0.725 nmpg and the diesels get approx. 1.0 nmpg. In our area diesel fuel averages between 8-15% less than gas as well so that is in addition to the less fuel used.
So the total fuel difference in cost per year between these boats 2 38's is $2,500-$3,000 where we are YMMV.
Although there are no exact rules these areas will be the general tradeoffs in your decisions.
Gas advantages
• Lower initial cost
• Low odor
• Normally no soot
• Mostly easier to find competent mechanic
• Generally lower parts costs
• More common fuel docks in some areas
Diesel advantages
• 30-35% better nmpg
• 40-45% less total fuel cost in our area
• Less manifolds & exhaust
• Lower flash point fuel
• Lower CO
• Sometimes lower insurance
• Holds same speed over larger swells
• More room around engines (I-6) vs v-8’s
Hope this helps
Having said that we cruise with a bunch of Sea Rays and 4 are very similar with 2 being diesel and 2 big block gas. A 37 gas, two 38's one gas one diesel and a 40 diesel. Over a number of seasons often cruising the same routs at the same speeds we have seen and discussed the differences especially with the two 38's.
At about 1,000 nautical miles per year / about 80 engine hours / about 50 engine hours
at cruise and 60-80 genset hours the gas boats get approx. 0.725 nmpg and the diesels get approx. 1.0 nmpg. In our area diesel fuel averages between 8-15% less than gas as well so that is in addition to the less fuel used.
So the total fuel difference in cost per year between these boats 2 38's is $2,500-$3,000 where we are YMMV.
Although there are no exact rules these areas will be the general tradeoffs in your decisions.
Gas advantages
• Lower initial cost
• Low odor
• Normally no soot
• Mostly easier to find competent mechanic
• Generally lower parts costs
• More common fuel docks in some areas
Diesel advantages
• 30-35% better nmpg
• 40-45% less total fuel cost in our area
• Less manifolds & exhaust
• Lower flash point fuel
• Lower CO
• Sometimes lower insurance
• Holds same speed over larger swells
• More room around engines (I-6) vs v-8’s
Hope this helps
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How much does the boat weigh? Anything over 20,000 lbs, I would not go with gas. My boat weighs 30,000 lbs and I have twin 450 cummins diesels. I set the throttles at cruise and never have to touch them again until I'm ready to slow down. My last boat, at 20,000 lbs had crusader 454's. I was working the throttles all the time to keep it on plane.
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I agree with Hogan. Once a boat gets over 20,000 lbs, you will find that diesel engines are also a little more maneuverable around the dock because at idle speeds they produce more torque and typically run larger props (or more pitch) and therefore "bite" the water better than gas engines.
Don't expect to really save money with diesels. What you save in fuel costs are more than made up in the cost of parts. Best points are they are safer and, if serviced properly and not abused will last longer than gas engines and will command a higher resale value.
Don't expect to really save money with diesels. What you save in fuel costs are more than made up in the cost of parts. Best points are they are safer and, if serviced properly and not abused will last longer than gas engines and will command a higher resale value.
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Something not yet mentioned:
all things being equal, the diesel boat in that size is far more desirable.
when the time comes to sell, she will sell for MORE and will sell FASTER.
unless you are looking for a dock queen, its a simple choice.
RWS
all things being equal, the diesel boat in that size is far more desirable.
when the time comes to sell, she will sell for MORE and will sell FASTER.
unless you are looking for a dock queen, its a simple choice.
RWS
It seems to me that most marine model diesels engines will outlast a gas counterpart.
Resale value will be higher on a diesel boat in most cases.
In my opinion being one of the people that had a choice 6 years ago I made the mistake of repowering with gas engines.
As boats approach 40 feet in length I can't think of a single reason to choose gas over diesel unless you are not leaving the dock.
Bill
Resale value will be higher on a diesel boat in most cases.
In my opinion being one of the people that had a choice 6 years ago I made the mistake of repowering with gas engines.
As boats approach 40 feet in length I can't think of a single reason to choose gas over diesel unless you are not leaving the dock.
Bill
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Bob, I see you are in Seelys Bay. A big plus not mentioned is, if you register the boat with Transport Canada instead of the province you can get construction/farm diesel delivered by truck. A big savings. If you are in a marina they will probably not allow this for their own reasons but at a town dock it is OK.
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Having had the pleasure of owning the same boat in has and diesel I can say a few things.
It's actually not a good comparison since diesel ips can't compare to has shafts.
So I won't comment on propulsion but the diesel definitely has more tongue and I never need to throttle up around the dock.
Engine room has so much more room with diesels as the motors are not as wide.
Fuel economy is a huge plus.
Range is another big plus.
My same 275 gallon tank lasts a lot longer with diesel so less fill ups are needed.
Oil change definaty costs more with diesels.
But the savings are offset by lack of platinum plugs.
The safety factor is a priceless benefit.
My gas boat I always worried about explosion.
Given a choice and only $20k difference I would go with diesel.
Resale alone will make that back and more!
It's actually not a good comparison since diesel ips can't compare to has shafts.
So I won't comment on propulsion but the diesel definitely has more tongue and I never need to throttle up around the dock.
Engine room has so much more room with diesels as the motors are not as wide.
Fuel economy is a huge plus.
Range is another big plus.
My same 275 gallon tank lasts a lot longer with diesel so less fill ups are needed.
Oil change definaty costs more with diesels.
But the savings are offset by lack of platinum plugs.
The safety factor is a priceless benefit.
My gas boat I always worried about explosion.
Given a choice and only $20k difference I would go with diesel.
Resale alone will make that back and more!
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Next year I plan to do it all myself. I wanted to watch how it was done by a real diesel IPS guy mechanic to learn.
All I need is a 2 inch ID marine hose to adapt the hose to. Been looking for a scrap piece to make a hose fitting to run motors on land.