Engine Efficiency Improvements over 20 years
 

There is also some concern that the newer, light-weight, higher-rpm diesels
won't have the same longevity as older, heavier, slower-turning varieties.
I'm not sure how this works out in practice.

I have also been under the same impression as some others in this thread,
that diesels are so much more expensive than gas engines that unless you're
using the boat commercially - heavy, regular use, day after day - that it
will be many, many years until the fuel savings catch up with your capital
costs. The sometimes controversial Pascoe
(www.yachtsurvey.com/GasDiesel.htm) favors gas engines for "smaller" boats.

A friend of mine has a 34-foot semi-planing boat with gas engines, and he
says that when he bought it new about 15 years ago, the __upgrade__ cost for
diesels was $50K (CDN)!!!

====

Charles T. Low
- remove "UN"
www.boatdocking.com/BDPhoto.html - Photo Contest
www.boatdocking.com
www.ctlow.ca/Trojan26 - my boat

====

"DSK" wrote in message
...
Rod McInnis wrote:
In general, a diesel engine weighs a lot more than a gas engine of the
same
horsepower.

30 years ago, that was true. Now I don't think the weight difference is
all that much, unless of course you're talking about comparing Rotax
engines... I don't think they put diesels in ultralight planes yet ;)

In this case, the specifics are in the last issue of Soundings, I
believe they gave the engine weights. IIRC there was not much difference
in engine weights, although the diesels were of slightly less HP they
had more torque and a much wider power band.

Fresh Breezes- Doug King

Engine Efficiency Improvements over 20 years
 

On Thu, 22 Jul 2004 07:21:24 -0400, "Charles T. Low"
wrote:

The sometimes controversial Pascoe
(www.yachtsurvey.com/GasDiesel.htm) favors gas engines for "smaller" boats.

=====================================

That's about right if you substitute the word "lighter" for "smaller".
Over 20,000 lbs or so it is difficult to get good performance without
diesels.

Engine Efficiency Improvements over 20 years
 

Charles T. Low wrote:
There is also some concern that the newer, light-weight, higher-rpm diesels
won't have the same longevity as older, heavier, slower-turning varieties.
I'm not sure how this works out in practice.

I have also been under the same impression as some others in this thread,
that diesels are so much more expensive than gas engines that unless you're
using the boat commercially - heavy, regular use, day after day - that it
will be many, many years until the fuel savings catch up with your capital

While it's true that it will take a lot of use for the more expensive
diesels to pay off monetarily despite the higher resale value, you also
have to count in the greater range as another advantage. For people who
boat close to gas stations, that's not important. But if you want to go
offshore or have good cruising range, diesels can get you out further
and back then gas engines.

Steve

Engine Efficiency Improvements over 20 years
 

Not to mention the fact that diesel doesn't go 'boom' when you light a
match next to it, unlike gas.

Engine Efficiency Improvements over 20 years
 

On Fri, 23 Jul 2004 10:49:12 +0200, A-MAze
wrote:
Not to mention the fact that diesel doesn't go 'boom' when you light a
match next to it, unlike gas.

=============================

And the fact that dock diesel is 60 to 90 cents/gallon cheaper.

Engine Efficiency Improvements over 20 years
 

In article ,
A-MAze wrote:

Not to mention the fact that diesel doesn't go 'boom' when you light a
match next to it, unlike gas.

and diesels keep running as long as the fuel flows, no ignition,
sparkplug, or carburator problems with diesels.


Bruce in alaska who hates sparkplugs......
--
add a 2 before @

Engine Efficiency Improvements over 20 years
 

I would expect someone in Alaska to be more influenced by another diesel
shortcoming (in addition to more expensive and heavy engines, stinky fuel and
exhaust, requiring extreme fuel cleanliness, and algae growing fuel): hard to
start in cold weather. I had a diesel Mercedes car once - never again. And
most of us continue to have gas cars today instead of diesel.

From a safety standpoint, I suppose the ultimate test is whether insurance
companies give a discount for diesel vs gas. They would have the data to
determine if one or the other was more likely to cause a claim.

Not to mention the fact that diesel doesn't go 'boom' when you light a
match next to it, unlike gas.

and diesels keep running as long as the fuel flows, no ignition,
sparkplug, or carburator problems with diesels.


Bruce in alaska who hates sparkplugs......

Engine Efficiency Improvements over 20 years
 

In article ,
(DUINK) wrote:

I would expect someone in Alaska to be more influenced by another diesel
shortcoming (in addition to more expensive and heavy engines, stinky fuel and
exhaust, requiring extreme fuel cleanliness, and algae growing fuel): hard to
start in cold weather. I had a diesel Mercedes car once - never again. And
most of us continue to have gas cars today instead of diesel.

All the things you cite above aren't really limitations in the
serviceablility of the engine. Filters are not a big deal if you don't
get water in your fuel, and your much more likly to get water, in Gas
than Diesel, from a Marine Fuel supplier. Cold weather is a problem if
you know how to operate a diesel engine in that climate. Why do you
think all those truckers carry hairdryers around with them in their
lockboxes? It ain't for their hair, son.

Bruce in alaska
--
add a 2 before @

Engine Efficiency Improvements over 20 years
 

If you are going to repower, figure out the how much gas you use per
year and multiply by what you pay to get an approximate annual fuel
bill. (You may not want to know this number.) Subtract the cost of
diesel times how much diesel you would burn to cover the same distance
to get annual fuel savings. How many years will it take to make up the
difference in the cost of repowering?

You should also consider the range issue and the fact that a new diesel
may outlast the new gas engine. For me to repower my 1987 26' cruiser in
gas might run $5000; diesel would be close to $20,000 since I also have
to change motor mounts, fuel systems, add insulation and more. I might
save about $1000 annually, figuring 150 hours of operation, the
different fuel consumption, and different fuel costs.

I'd be crazy to do this in a 17 year old boat, but I just might....

Capt. Jeff

Engine Efficiency Improvements over 20 years
 

In article ,
Tamaroak wrote:

If you are going to repower, figure out the how much gas you use per
year and multiply by what you pay to get an approximate annual fuel
bill. (You may not want to know this number.) Subtract the cost of
diesel times how much diesel you would burn to cover the same distance
to get annual fuel savings. How many years will it take to make up the
difference in the cost of repowering?

You should also consider the range issue and the fact that a new diesel
may outlast the new gas engine. For me to repower my 1987 26' cruiser in
gas might run $5000; diesel would be close to $20,000 since I also have
to change motor mounts, fuel systems, add insulation and more. I might
save about $1000 annually, figuring 150 hours of operation, the
different fuel consumption, and different fuel costs.

I'd be crazy to do this in a 17 year old boat, but I just might....

Capt. Jeff


There's also the comfort factor. We spent $12k to switch a 20 year old
boat from gas to diesel. A decade later, no regrets. On the contrary!

Just this morning, we spent 2 hours racing a front to our marina at full
power to get in 20 minutes faster. That the engine would complain never
entered my mind, since only 1200 hours are on the clock.

Oh, just as I got the docklines on, the monsoon we were racing hit.

--
Jere Lull
Xan-a-Deux ('73 Tanzer 28 #4 out of Tolchester, MD)
Xan's Pages: http://members.dca.net/jerelull/X-Main.html
Our BVI FAQs (290+ pics) http://homepage.mac.com/jerelull/BVI/