On Thu, 3 Apr 2008 20:00:58 -0700 (PDT), "
wrote:

On Apr 3, 3:24 pm, Bruce in Bangkok wrote:
I would like to make the suggestion that individuals who pose
questions, especially complex questions like the recent Yanmar
governor problem, be encouraged to post the results. What did he/she
do and what was the result.

Sorry not to report back. I certainly would have posted with glee if
I had fixed it. All I ended up doing was taking a small access port
off that though which I could see, but not remove and measure the
springs on the throttle side of the assembly. It all looked lovely in
there but there was a little stiffness on the throttle crank itself.
So I lubed its axle and worked it a bit. I got one disconcerting
"thunk" out of the mechanism, put it all back together and ran it and
got the same failure then ran it again and it worked fine... By
looking at it I did convince myself that the fault was not in the
setting of the torque limiter. The current plan is to take off the
gear casing next time I pull the motor and inspect the bushings and
springs... Meanwhile I will continue to work around it. Many thanks
for your help and mea culpa for my silence.

Cheers,

-- Tom.

I wasn't "pin pointing" you, sorry if it sounded as though I was,
simply using your problem as an example of something that I'd like to
learn more about as there are zillions of Yanmar engines and I'd like
to know how to fix that problem.

I 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.

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

"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.

Lew

"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.

On Fri, 4 Apr 2008 11:01:39 +0200, "Edgar"
wrote:


"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.


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)

"Bruce in Bangkok" wrote in message
...
On Fri, 4 Apr 2008 11:01:39 +0200, "Edgar"
wrote:


"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.


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.

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

"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..

"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

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/

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)

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/