wrote:
"Free & Clear's" twin 300-HP Yanmar diesels were installed
in 2000 and can now be considered "broken in" with only 775 hours

They are way more than broken in, more accurately, half used up or
possibly more. We are not talking about 3,000 lb cast iron engines
that are built to last forever. The Yanmars are lightweights that will
be lucky to make it much past 1,500 hours without major overhauls. The
fuel tanks, hull, deck and hull/deck joint should also be regarded as
highly suspect in a high usage boat of that age.

Sounds like you've been reading David Pascoe's website. He places the
life expectancy of most diesel engines somewhere near 1,000 hours,
IIRC. We need to get the word out to thousands of people well beyond
1500 hours on their Yanmars that they are overdue for a major overhaul.
I do agree that these engines are unlikely to ever see the 5000 or 6000
hours often achieved with older, lower RPM engines like a Ford Lehman,
my original Perkins (that died only due to a manifold failure around
4000 hours), etc. But to predict they won't even survive as long as a
well maintained marinized automobile gas engine is far too negative,
IMO. Did you know that Yanmar scored better than Volvo, Perkins, and
some other top names in a survey of actual diesel engine owners in the
Jan 2006 issue of Cruising World?

A thorough survey would confirm or defuse concerns about the hull,
deck, etc. and nobody should ever buy a used boat without a survey.

wrote in message
ps.com...


Sounds like you've been reading David Pascoe's website. He places the
life expectancy of most diesel engines somewhere near 1,000 hours,
IIRC. We need to get the word out to thousands of people well beyond
1500 hours on their Yanmars that they are overdue for a major overhaul.
I do agree that these engines are unlikely to ever see the 5000 or 6000
hours often achieved with older, lower RPM engines like a Ford Lehman,
my original Perkins (that died only due to a manifold failure around
4000 hours), etc. But to predict they won't even survive as long as a
well maintained marinized automobile gas engine is far too negative,
IMO. Did you know that Yanmar scored better than Volvo, Perkins, and
some other top names in a survey of actual diesel engine owners in the
Jan 2006 issue of Cruising World?


I think (simply my opinion) that a modern diesel boat engine's lifespan is
inversely proportional to it's horsepower. I know a guy that's been through
3 engine rebuilds or replacements of both Yanmar 600 hp engines on his boat
in 6 years. He did a lot of fishing trips and never got much over 1000 hours
on any of them.

RCE

RCE wrote:
wrote in message
ps.com...


Sounds like you've been reading David Pascoe's website. He places the
life expectancy of most diesel engines somewhere near 1,000 hours,
IIRC. We need to get the word out to thousands of people well beyond
1500 hours on their Yanmars that they are overdue for a major overhaul.
I do agree that these engines are unlikely to ever see the 5000 or 6000
hours often achieved with older, lower RPM engines like a Ford Lehman,
my original Perkins (that died only due to a manifold failure around
4000 hours), etc. But to predict they won't even survive as long as a
well maintained marinized automobile gas engine is far too negative,
IMO. Did you know that Yanmar scored better than Volvo, Perkins, and
some other top names in a survey of actual diesel engine owners in the
Jan 2006 issue of Cruising World?


I think (simply my opinion) that a modern diesel boat engine's lifespan is
inversely proportional to it's horsepower. I know a guy that's been through
3 engine rebuilds or replacements of both Yanmar 600 hp engines on his boat
in 6 years. He did a lot of fishing trips and never got much over 1000 hours
on any of them.

RCE

I wish I could recall where to find it, but there has been a study
conducted and a theory advanced that there's a direct relationship
between the amount of fuel a diesel engine consumes and its life
expectancy. The theory bases life expectancy on gallons consumed,
rather than on hours operated. Under such a premise, any fuel
consumption chart for a high HP diesel engine will reveal just how
costly pushing the engine beyond
the most efficient point in the curve can be, in terms of engine life
expectancy as well as the fuel bill. I wonder what your acquaintance's
experience would have been at just a few hundred RPM slower, where his
fuel consumption might have been substantially less. If he's wearing
out a diesel in 1000 hours, he's got the wrong engines for his
application or he's pushing them way too hard, IMO.

Relevant aside: I was just aboard a new Silverton with Yanmars, and
learned that the factory *recommends* that the engines be cruised at
within 200 RPM of WOT and *recommends* that they run totally wide open
for up to 30% of total operating time.
Interesting recommendations, to say the least.

I should have sent this a long time ago but, thanks for all of your posts.
I always enjoy at least glancing at the ones on subjects not high on my list
of priorities/interests, and take my time to thoroughly enjoy reading the
posts on those that have specific interest to me.

wrote in message
oups.com...

RCE wrote:
wrote in message
ps.com...


Sounds like you've been reading David Pascoe's website. He places the
life expectancy of most diesel engines somewhere near 1,000 hours,
IIRC. We need to get the word out to thousands of people well beyond
1500 hours on their Yanmars that they are overdue for a major overhaul.
I do agree that these engines are unlikely to ever see the 5000 or 6000
hours often achieved with older, lower RPM engines like a Ford Lehman,
my original Perkins (that died only due to a manifold failure around
4000 hours), etc. But to predict they won't even survive as long as a
well maintained marinized automobile gas engine is far too negative,
IMO. Did you know that Yanmar scored better than Volvo, Perkins, and
some other top names in a survey of actual diesel engine owners in the
Jan 2006 issue of Cruising World?


I think (simply my opinion) that a modern diesel boat engine's lifespan
is
inversely proportional to it's horsepower. I know a guy that's been
through
3 engine rebuilds or replacements of both Yanmar 600 hp engines on his
boat
in 6 years. He did a lot of fishing trips and never got much over 1000
hours
on any of them.

RCE

I wish I could recall where to find it, but there has been a study
conducted and a theory advanced that there's a direct relationship
between the amount of fuel a diesel engine consumes and its life
expectancy. The theory bases life expectancy on gallons consumed,
rather than on hours operated. Under such a premise, any fuel
consumption chart for a high HP diesel engine will reveal just how
costly pushing the engine beyond
the most efficient point in the curve can be, in terms of engine life
expectancy as well as the fuel bill. I wonder what your acquaintance's
experience would have been at just a few hundred RPM slower, where his
fuel consumption might have been substantially less. If he's wearing
out a diesel in 1000 hours, he's got the wrong engines for his
application or he's pushing them way too hard, IMO.

Relevant aside: I was just aboard a new Silverton with Yanmars, and
learned that the factory *recommends* that the engines be cruised at
within 200 RPM of WOT and *recommends* that they run totally wide open
for up to 30% of total operating time.
Interesting recommendations, to say the least.

wrote in message
oups.com...


I wish I could recall where to find it, but there has been a study
conducted and a theory advanced that there's a direct relationship
between the amount of fuel a diesel engine consumes and its life
expectancy. The theory bases life expectancy on gallons consumed,
rather than on hours operated. Under such a premise, any fuel
consumption chart for a high HP diesel engine will reveal just how
costly pushing the engine beyond
the most efficient point in the curve can be, in terms of engine life
expectancy as well as the fuel bill. I wonder what your acquaintance's
experience would have been at just a few hundred RPM slower, where his
fuel consumption might have been substantially less. If he's wearing
out a diesel in 1000 hours, he's got the wrong engines for his
application or he's pushing them way too hard, IMO.

Relevant aside: I was just aboard a new Silverton with Yanmars, and
learned that the factory *recommends* that the engines be cruised at
within 200 RPM of WOT and *recommends* that they run totally wide open
for up to 30% of total operating time.
Interesting recommendations, to say the least.


The manual for my Volvos (TAMP-63P -370hp) says the same thing, in fact they
give you a placard to install by the throttles that says "Recommended cruise
RPM = WOT minus 200 RPM. Doesn't say anything about running WOT
specifically, but general knowledge among diesel owners is to crank 'em up
for a mile or two when returning after cruising for an extended period of
time.

The theory on engine life and fuel consumption makes a lot of sense. As I
mentioned, the person with the 600 hp Yanmars does a lot of fishing and it
includes many hours of high speed, (30+ knots) running to get well offshore
(NE Canyons). His boat was manufactured by:

http://www.eastbayboatworks.com/

RCE

wrote in message
oups.com...

RCE wrote:
wrote in message
ps.com...



I think (simply my opinion) that a modern diesel boat engine's lifespan
is
inversely proportional to it's horsepower. I know a guy that's been
through
3 engine rebuilds or replacements of both Yanmar 600 hp engines on his
boat
in 6 years. He did a lot of fishing trips and never got much over 1000
hours
on any of them.

RCE


I screwed up. His engines are *not* Yanmar. They are Manns.

RCE

RCE wrote:
wrote in message
oups.com...

RCE wrote:
wrote in message
ps.com...



I think (simply my opinion) that a modern diesel boat engine's lifespan
is
inversely proportional to it's horsepower. I know a guy that's been
through
3 engine rebuilds or replacements of both Yanmar 600 hp engines on his
boat
in 6 years. He did a lot of fishing trips and never got much over 1000
hours
on any of them.

RCE


I screwed up. His engines are *not* Yanmar. They are Manns.

RCE

Oh....

That might explain it, but I didn't know Dave was trying to manufacture
diesel engines.
(just kidding)

FWIW:
I think the correct spelling is M-A-N
http://www.mandiesel.com/mome2.htm

There was one guy from back east who was leading a virtual crusade
against MAN Diesel just a few years ago. He kept experiencing (or at
least claimed he was experiencing) piston failures at very low hours. I
thought I heard he settled with MAN and as a condition of the
settlement he had to take down his defamatory web sites. Wouldn't be
your neighbor/acquaintance, would it?

wrote in message
ups.com...

RCE wrote:
wrote in message
oups.com...

RCE wrote:
wrote in message
ps.com...



I think (simply my opinion) that a modern diesel boat engine's
lifespan
is
inversely proportional to it's horsepower. I know a guy that's been
through
3 engine rebuilds or replacements of both Yanmar 600 hp engines on his
boat
in 6 years. He did a lot of fishing trips and never got much over 1000
hours
on any of them.

RCE


I screwed up. His engines are *not* Yanmar. They are Manns.

RCE

Oh....

That might explain it, but I didn't know Dave was trying to manufacture
diesel engines.
(just kidding)

FWIW:
I think the correct spelling is M-A-N
http://www.mandiesel.com/mome2.htm

There was one guy from back east who was leading a virtual crusade
against MAN Diesel just a few years ago. He kept experiencing (or at
least claimed he was experiencing) piston failures at very low hours. I
thought I heard he settled with MAN and as a condition of the
settlement he had to take down his defamatory web sites. Wouldn't be
your neighbor/acquaintance, would it?



No. He's not that type. Any problems he would have would be taken care of
through his lawyer.

RCE

They didn't get the nick name "MANgrenades" for nothing.

And I'm sorry Chuck, but I'd be shocked if anybody payed even 90% of the asking price of this boat.

http://yachtworld.com/core/listing/p...95&slim=quick&

No matter how much you upgrade it, it's still a 1984 "Swellcraft".

On 20 Feb 2006 07:21:46 -0800, wrote:

I wish I could recall where to find it, but there has been a study
conducted and a theory advanced that there's a direct relationship
between the amount of fuel a diesel engine consumes and its life
expectancy. The theory bases life expectancy on gallons consumed,
rather than on hours operated.

Fuel consumed relates directly to horsepower generated times hours of
operation, and is more or less meaningless as a durability indicator
except between comparable engines. What are very definite indicators
however are horsepower per pound and horsepower per cubic inch. The
Yanmars rate poorly on both counts since they are light weight, highly
stressed, turbo charged engines putting out a lot of power for their
weight, actually weighing less than the 350 hp gas engines that they
replaced. All turbo charged diesels are high maintenance relative to
their naturally aspirated brethren but some are more conservatively
engineered than others.