Engine Efficiency Improvements over 20 years
 

Hello,

I have a 1981 Carver with twin 270 Crusader engines nearing the end of their
lifecycle. I'm sure I can get another year or two from them if I treat them
well, but I was wondering if by doing so I was actually ending up paying
more. By that I mean is the improvements in efficiency in engines enough
over the last 20 years that I would be ahead in gas savings by getting rid
of them now?

Thanks

Kevin

Engine Efficiency Improvements over 20 years
 

In article s.com,
"KJEJ Harris" wrote:

Hello,

I have a 1981 Carver with twin 270 Crusader engines nearing the end of their
lifecycle. I'm sure I can get another year or two from them if I treat them
well, but I was wondering if by doing so I was actually ending up paying
more. By that I mean is the improvements in efficiency in engines enough
over the last 20 years that I would be ahead in gas savings by getting rid
of them now?

Thanks

Kevin



Replace them with some very nice Volvo, John Deere, or Cat Diesels
and save a pile on fuel, and maintainance.


me Diesels are your friend.........

Engine Efficiency Improvements over 20 years
 

Soundings just had an article on a guy who replaced older gas engines with
diesel. He saved thousands on fuel and picked up a fair amount of range as
well. The article ran within the last month or two.


"KJEJ Harris" wrote in message
ogers.com...
Hello,

I have a 1981 Carver with twin 270 Crusader engines nearing the end of
their
lifecycle. I'm sure I can get another year or two from them if I treat
them
well, but I was wondering if by doing so I was actually ending up paying
more. By that I mean is the improvements in efficiency in engines enough
over the last 20 years that I would be ahead in gas savings by getting rid
of them now?

Thanks

Kevin

Engine Efficiency Improvements over 20 years
 

"Tom Hunter" wrote in message
news:Zq8Lc.122257$MB3.84466@attbi_s04...
Soundings just had an article on a guy who replaced older gas engines with
diesel. He saved thousands on fuel and picked up a fair amount of range
as
well. The article ran within the last month or two.

Is it cost effective due to the higher price of diesels. I would think that
you would have to do an awful lot of running to come out even. Granted the
diesels will last forever and fuel is cheaper, but it comes with an initial
cost.

Leanne

Engine Efficiency Improvements over 20 years
 

"KJEJ Harris" wrote in message
ogers.com...


. By that I mean is the improvements in efficiency in engines enough
over the last 20 years that I would be ahead in gas savings by getting rid
of them now?


For your application, the improvements are pretty small.

Modern computer controlled, fuel injected engines will significantly reduce
emissions, start easier, and operate more efficiently over a wider range of
altitudes, temperatures, and speeds. Assuming that your boat doesn't
deviate much from sea level, and doesn't operate at freezing temperatures,
and most of your cruising is at a constant speed, you won't see a dramatic
improvment in fuel economy.

If you rely on the engines and having them fail could put you in danger then
I would say to swap them out before they die. If having an engine die
simply means that it will take you a bit longer to get back to your dock
then I would be tempted to run them till they didn't run anymore.

As far as switching to diesels: You would have to put a lot of hours on the
engines to recover the cost. If you replace the existing engines with a
similar size gas engine then you can reuse the transmissions, shafts and
prop. If you change to diesels, you will need to modify or replace the
fuel tanks (they will need a fuel return line), replace the transmissions,
make new motor mounts, new dash insturments, etc. It can end up costing you
an extra $10,000 to switch to diesel. That will buy a lot of gas.....

Rod

Engine Efficiency Improvements over 20 years
 

"Tom Hunter" wrote
Soundings just had an article on a guy who replaced older gas engines with
diesel. He saved thousands on fuel and picked up a fair amount of range

Leanne wrote:
Is it cost effective due to the higher price of diesels.

It depends of course on how you calculate cost effectiveness. This
particular boat was a planing boat, and the increased efficiency of the
diesels allowed the boat to carry somewhat less fuel, making it lighter
& easier to plane, and increased range at the same time.

The engines were expensive, but over their expected service life they
will more than repay the greater cost *if* the owner often uses the boat
to go longer distances in open water, as planned.

Fresh Breezes- Doug King

Engine Efficiency Improvements over 20 years
 

Take a look at the cost of replacement. As I recall replacing the gas
engines in the mag article included the engines, transmissions, struts,
motor mounts props instruments, and cutlass bearings (everything but the gas
tanks) and the total cost was about $80,000. If you are capable of doing
your own installation (and have the time) you might cut these costs in half.
If you expect to put a lot of miles on your boat and your boat is a classic
the reduced fuel costs, tune up costs and increased resale value might make
this pay.

I am also Carver owner (1987 3257 Montego) I met a guy who dieselized his
Montego (beautiful installation) did a lot of his own work and it still cost
him $50K both our boat and his are in very nice condition. We put a teak and
holly sole in ours ($2.5K). A broker said given the market for used Carvers
(which is good) we had increased the value of our boat more than he had.

One last thought, a guy at our club just bought a very nice TollyCraft 40.
Immediately replaced the 454 V-8s with diesels even though the 454s were in
good shape, (cost well over $80K) but the diesels are "shipier". Boating is
not a rational activity, go with what turns you on.
"Rod McInnis" wrote in message
...

"KJEJ Harris" wrote in message
ogers.com...


. By that I mean is the improvements in efficiency in engines enough
over the last 20 years that I would be ahead in gas savings by getting
rid
of them now?


For your application, the improvements are pretty small.

Modern computer controlled, fuel injected engines will significantly
reduce
emissions, start easier, and operate more efficiently over a wider range
of
altitudes, temperatures, and speeds. Assuming that your boat doesn't
deviate much from sea level, and doesn't operate at freezing temperatures,
and most of your cruising is at a constant speed, you won't see a dramatic
improvment in fuel economy.

If you rely on the engines and having them fail could put you in danger
then
I would say to swap them out before they die. If having an engine die
simply means that it will take you a bit longer to get back to your dock
then I would be tempted to run them till they didn't run anymore.

As far as switching to diesels: You would have to put a lot of hours on
the
engines to recover the cost. If you replace the existing engines with a
similar size gas engine then you can reuse the transmissions, shafts and
prop. If you change to diesels, you will need to modify or replace the
fuel tanks (they will need a fuel return line), replace the transmissions,
make new motor mounts, new dash insturments, etc. It can end up costing
you
an extra $10,000 to switch to diesel. That will buy a lot of gas.....

Rod

Engine Efficiency Improvements over 20 years
 

"DSK" wrote in message
...



This
particular boat was a planing boat, and the increased efficiency of the
diesels allowed the boat to carry somewhat less fuel, making it lighter
& easier to plane,

In general, a diesel engine weighs a lot more than a gas engine of the same
horsepower. I would think that you would have to be talking about some very
large fuel tanks to have the fuel weight significantly counteract the engine
weight.

Rod

Engine Efficiency Improvements over 20 years
 

Rod McInnis wrote:
"DSK" wrote in message
...




This
particular boat was a planing boat, and the increased efficiency of the
diesels allowed the boat to carry somewhat less fuel, making it lighter
& easier to plane,


In general, a diesel engine weighs a lot more than a gas engine of the same
horsepower. I would think that you would have to be talking about some very
large fuel tanks to have the fuel weight significantly counteract the engine
weight.

The weight difference isn't *that* much. Maybe a hundred pounds or so
more per engine for a typical setup, give or take. That's only like 16
gals of fuel in weight. When you're talking about tanks of even only 50
gals or so, you can easily cut out 16 and still have the diesel get the
same range. For larger tanks, the diesel will have more range for 16
gals less fuel capacity.

Steve

Engine Efficiency Improvements over 20 years
 

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