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Edgar April 4th 08 07:45 PM

A suggestion
 

"Capt. JG" wrote in message
news:er2dnQ_MYo2s7WvanZ2dnUVZ_uuonZ2d@bayareasolut ions...

Actually diesel engines aren't that sensitive. Certainly one should
not idle them for long periods - hours, but it does no damage to let
an engine idle while you are clearing up the lines or what ever. Ever
been into a truck stop on a winter morning and seen the lines of
Peterbilt's sitting there idling while the driver is in having
breakfast.

Bruce-in-Bangkok
(correct email address for reply)



I've had them idle all night... not sure what the idle speed was... wasn't
in charge, just a passenger.



All that guy's post proves is that truck drivers are insensitive to their
motors, not that the diesels are insensitive to prolonged idling.
Most truck drivers, I suspect, do not have to pay the maintenance costs of
the machines they drive. They much prefer to come back to a warm cab after
breakfast..
However, it has to be said that those engines are warmed up when they
arrive at the truckstop. Idling a cold engine to warm it up is much worse
than what they are doing, stupid though it is..



Capt. JG April 4th 08 07:49 PM

A suggestion
 
"Edgar" wrote in message
...

"Capt. JG" wrote in message
news:er2dnQ_MYo2s7WvanZ2dnUVZ_uuonZ2d@bayareasolut ions...

Actually diesel engines aren't that sensitive. Certainly one should
not idle them for long periods - hours, but it does no damage to let
an engine idle while you are clearing up the lines or what ever. Ever
been into a truck stop on a winter morning and seen the lines of
Peterbilt's sitting there idling while the driver is in having
breakfast.

Bruce-in-Bangkok
(correct email address for reply)



I've had them idle all night... not sure what the idle speed was...
wasn't in charge, just a passenger.



All that guy's post proves is that truck drivers are insensitive to their
motors, not that the diesels are insensitive to prolonged idling.
Most truck drivers, I suspect, do not have to pay the maintenance costs of
the machines they drive. They much prefer to come back to a warm cab
after breakfast..
However, it has to be said that those engines are warmed up when they
arrive at the truckstop. Idling a cold engine to warm it up is much worse
than what they are doing, stupid though it is..



I don't know about most, but my guess is that a substantial portion of
truckers are independents who likely do pay for maintenance. You're right
about the warm-up... the engines are already hot from long driving. I can't
recall if the driver ever shut the thing off in 3000 miles except to stop
for fuel or a bio stop.

--
"j" ganz @@
www.sailnow.com




Wayne.B April 4th 08 08:43 PM

A suggestion
 
On Fri, 4 Apr 2008 11:49:03 -0700, "Capt. JG"
wrote:

I don't know about most, but my guess is that a substantial portion of
truckers are independents who likely do pay for maintenance. You're right
about the warm-up... the engines are already hot from long driving. I can't
recall if the driver ever shut the thing off in 3000 miles except to stop
for fuel or a bio stop.


We once had a post here from a guy who was responsible for diesel
maintenance on a fleet of trucks at a gold mine in northern Canada.
He said that basically the trucks idled all winter, over 3,000 engine
hours each. He said that by spring the engines were mostly junk if I
recall correctly.

In contrast, a heavy duty diesel in normal service, and with good
maintenance, will go 5,000 to 10,000 hours between overhauls.




Edgar April 4th 08 09:20 PM

A suggestion
 

"Wayne.B" wrote in message
...

We once had a post here from a guy who was responsible for diesel
maintenance on a fleet of trucks at a gold mine in northern Canada.
He said that basically the trucks idled all winter, over 3,000 engine
hours each. He said that by spring the engines were mostly junk if I
recall correctly.

In contrast, a heavy duty diesel in normal service, and with good
maintenance, will go 5,000 to 10,000 hours between overhauls.


That figures.
Many years ago my employers sent me to Canada in the winter to find out how
they managed to start diesels on oilrigs in winter. I found that basically
they never stopped them and even moved them from place to place still
running. I learned some drastic and time consuming methods they had devised
to start an engine that had been allowed to get really cold with the oil in
the sump turned to thick goo.



Jere Lull April 5th 08 07:51 AM

A suggestion
 
On 2008-04-04 05:01:39 -0400, "Edgar" said:

"Lew Hodgett" wrote in message
news:iMjJj.10032$s27.7854@trnddc02...

"Bruce in Bangkok" wrote:

read a reference to one of your posts, quoted in part by Roger, that
sounded as though the RPM was only unstable at low RPM, I remember
something about 1,000 RPM.



Most diesels need to idle in the 1300-1500 RPM area in order to generate
enough waste heat to prevent
"wet-stacking" which will cause glazing of the cylinder walls, creating a
VERY expensive repair.


Much better to cut out prolonged idling and get some load on sooner.
Start up, and by the time you have checked the exhaust for cooling water,
gone forward and cast off the mooring ropes the engine is ready to go.
In other words, just long enough to spread some oil around inside the
engine.
If you cannot get load on for some time then stop the engine until you are
ready.


Yours is actually off the original topic (though entirely appropriate
for the newsgroup), but exactly describes my techniques over the past
15 or so seasons.

It's almost disappointing that those techniques have resulted in zero
required adjustments or repairs in over 1000 hours' operation. I do the
tests, the tests say "no problem".

--
Jere Lull
Tanzer 28 #4 out of Tolchester, MD
Xan's pages: http://web.mac.com/jerelull/iWeb/Xan/
Our BVI trips & tips: http://homepage.mac.com/jerelull/BVI/


Jere Lull April 5th 08 08:01 AM

A suggestion
 
On 2008-04-04 15:43:09 -0400, Wayne.B said:

We once had a post here from a guy who was responsible for diesel
maintenance on a fleet of trucks at a gold mine in northern Canada.
He said that basically the trucks idled all winter, over 3,000 engine
hours each. He said that by spring the engines were mostly junk if I
recall correctly.


I'm too lazy/busy to do the implied required search, as following this
group is a minor part of my daily activity, but my recollection of that
thread and observation of truckers in my own area tells me that keeping
the engine idling doesn't significantly add to the engine's demise. In
fact, if the engines are shut down in those extremely low temperatures,
drastic measures more injurious to to the engines are required to
restart them.

--
Jere Lull
Tanzer 28 #4 out of Tolchester, MD
Xan's pages: http://web.mac.com/jerelull/iWeb/Xan/
Our BVI trips & tips: http://homepage.mac.com/jerelull/BVI/


Bruce in Bangkok[_5_] April 5th 08 12:54 PM

A suggestion
 
On Fri, 4 Apr 2008 22:20:30 +0200, "Edgar"
wrote:


"Wayne.B" wrote in message
.. .

We once had a post here from a guy who was responsible for diesel
maintenance on a fleet of trucks at a gold mine in northern Canada.
He said that basically the trucks idled all winter, over 3,000 engine
hours each. He said that by spring the engines were mostly junk if I
recall correctly.

In contrast, a heavy duty diesel in normal service, and with good
maintenance, will go 5,000 to 10,000 hours between overhauls.


That figures.
Many years ago my employers sent me to Canada in the winter to find out how
they managed to start diesels on oilrigs in winter. I found that basically
they never stopped them and even moved them from place to place still
running. I learned some drastic and time consuming methods they had devised
to start an engine that had been allowed to get really cold with the oil in
the sump turned to thick goo.

I never worked up north but we did do some bids with one of the
Canadian drilling companies and I had assumed from what they told me
that all the winterized rigs had water and oil heaters installed in
the engines. Certainly the floor and mast are protected and heated
well enough that you can work there.

..
Bruce-in-Bangkok
(correct email address for reply)

Bruce in Bangkok[_5_] April 5th 08 02:48 PM

A suggestion
 
On Sat, 05 Apr 2008 06:51:26 GMT, Jere Lull wrote:

On 2008-04-04 05:01:39 -0400, "Edgar" said:

"Lew Hodgett" wrote in message
news:iMjJj.10032$s27.7854@trnddc02...

"Bruce in Bangkok" wrote:

read a reference to one of your posts, quoted in part by Roger, that
sounded as though the RPM was only unstable at low RPM, I remember
something about 1,000 RPM.


Most diesels need to idle in the 1300-1500 RPM area in order to generate
enough waste heat to prevent
"wet-stacking" which will cause glazing of the cylinder walls, creating a
VERY expensive repair.


Much better to cut out prolonged idling and get some load on sooner.
Start up, and by the time you have checked the exhaust for cooling water,
gone forward and cast off the mooring ropes the engine is ready to go.
In other words, just long enough to spread some oil around inside the
engine.
If you cannot get load on for some time then stop the engine until you are
ready.


Yours is actually off the original topic (though entirely appropriate
for the newsgroup), but exactly describes my techniques over the past
15 or so seasons.

It's almost disappointing that those techniques have resulted in zero
required adjustments or repairs in over 1000 hours' operation. I do the
tests, the tests say "no problem".


The problem is that " Idle" is a relative term. I just finished
overhauling the governor for a Gardner engine 6 cylinder engine that
turned 1150 RPM at full throttle, and idled at 500 RPM. An 18 Ltr
engine producing 170 H.P. A little hard to get it up to the
recommended 1300 - 1500 RPM :-)

I also saw, but didn't work on, a single cylinder semi-diesel that ran
at 200 RPM. I asked the Motor-man how long it had been running and he
told me that he had been there for five years and it was running when
he got there and never stopped during his stay.

Somehow this dire warning not to idle a diesel doesn't seem to apply
to some engines. I think that if you substitute "lightly loaded" for
"idle" you might more accurately describe the condition.

As an aside, I have been fooling with these engines for some 50 or 60
years and the only people I have ever heard talk about not idling
diesels are boat people and primarily yacht people. Heavy trucks,
drilling rigs, heavy equipment, fishing boats, all frequently idle or
run at low power for long periods with no apparent problems.

Now I'm not trying to say that yachties don't know what they are
talking about but it does seem strange that they seem to be the only
people that talk about "not idling engines".

I suspect, but can't prove that yacht engines are seldom run at
maximum continuous horsepower settings for any length of time while
most commercial engines are. A bulldozer, for example will operate at
either idle or full throttle all its working life. Generator sets are
usually sized to work at about 90% of maximum continuous rating. I
installed a 1500 HP compressor engine that was sized to operate at 90%
of maximum. That engine, by the way, was overhauled after 5 years of
24 hour a day operation, some 40,000 hours of operation. And that
overhaul was done primarily because the plant had to be shut down to
replace some piping and the manager decided that as long as the plant
was down for a month they "might as well overhaul the engine".

My own suspicions are that if you run an engine for long periods at
light loads, as many people do when charging batteries you are asking
for problems. Particularly if you don't follow that low load period
with a period at nearly full power.

My own Perkins, overhauled 8 years ago is run at 2,000 RPM to charge
batteries and at the same RPM when motoring. Other then that I don't
pay any attention to whether it is idling or not. If I'm rigging the
mooring lines it idles. It doesn't burn any more oil today then it did
just after I overhauled it....


Bruce-in-Bangkok
(correct email address for reply)

Edgar April 5th 08 05:22 PM

A suggestion
 

"Bruce in Bangkok" wrote in message
...
That figures.

Many years ago my employers sent me to Canada in the winter to find out
how
they managed to start diesels on oilrigs in winter. I found that basically
they never stopped them and even moved them from place to place still
running. I learned some drastic and time consuming methods they had
devised
to start an engine that had been allowed to get really cold with the oil
in
the sump turned to thick goo.

I never worked up north but we did do some bids with one of the
Canadian drilling companies and I had assumed from what they told me
that all the winterized rigs had water and oil heaters installed in
the engines. Certainly the floor and mast are protected and heated
well enough that you can work there.

Thet may well do so now. Like I said it was _many_ years ago and things were
more basic then..



Jere Lull April 6th 08 01:31 AM

A suggestion
 
On 2008-04-05 09:48:23 -0400, Bruce in Bangkok said:

I suspect, but can't prove that yacht engines are seldom run at maximum
continuous horsepower settings for any length of time while most
commercial engines are.


Talking around the docks, and here, I find that most 'yacht' engines
are also either at idle or 80+% of designed revs.

I'm a bit unusual that I normally power at less than 80% of the
engine's max revs to maximize fuel economy. At 70-75% of max revs, we
get 25-30 mpg. 80% has us pushing against hull speed. Full revs push us
over hull speed, and I've only done that twice in 15 seasons.

Most sailors run at high power when they motor. If they turn the motor
on, they're by definition in a hurry.

--
Jere Lull
Tanzer 28 #4 out of Tolchester, MD
Xan's pages: http://web.mac.com/jerelull/iWeb/Xan/
Our BVI trips & tips: http://homepage.mac.com/jerelull/BVI/



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