
Mark Erdos
Teun,
Common rail
engines have been around for years and while they offer lower emissions and
soot from the exhaust they are not the cure-all. The thing to remember here is
all marine diesel engines are engines designed for land adapted to a marine
application. No diesel engine is designed to run at 25% power for days on end. If
a land based application called for only 25 hp then a 25 hp engine would be
used, not a 110 hp engine. It is my opinion the even the most modern newest technologically
advanced diesel engine still has emission issues (soot and carbon buildup) at
low end rpms. Look at the recent history of VW and how they adjusted the
software of the engine to trick the emissions computers. They did this because their
latest efforts at design and massive expenditure failed to produce a clean
burning diesel engine.
So, the question
I have for you is, what does it hurt to push up the RPM once in a while? If the
engine is designed to run at x RPM then it should be able to run at 80% of x
rpm for at least five minutes per hour, should it not?
With best
regards,
Mark
Skipper
Sailing Vessel
- Cream Puff - SM2K - #275
Currently
cruising - Curacao
www.creampuff.us
From:
amelyachtowners@... [mailto:amelyachtowners@...]
Sent: Saturday, July 7, 2018 7:30 PM
To: amelyachtowners@...
Subject: RE: [Amel Yacht Owners] engine cruising RPM
Importance: High
Hi Porter,
I understood you had a
new VOLVO installed. If so, and it is a common rail, then there is NO
need to run the engine on high rpms to “burn out the soot”.
This is the specific
instruction I got this week from the SYDNEY VOLVO technician installing my
VOLVO D3 110 H here in NOUMEA NEW CALEDONIA.
Best
Regards Teun
AMELIT
54 – 128
NOUMEA
NEW CALEDONIA
Jul 08, 2018 10:27:44
From:
amelyachtowners@... [mailto:amelyachtowners@...]
Sent: Sunday, July 08, 2018 10:24 AM
To: amelyachtowners@...
Subject: Re: [Amel Yacht Owners] engine cruising RPM
Thanks Mark.
If
temp is the final data point, we cruise at about 79-80. What should be the goal?
toggle quoted messageShow quoted text
On Jul 7, 2018, at 11:13 AM, 'Mark Erdos' mcerdos@...
[amelyachtowners] < amelyachtowners@...>
wrote:
Porter,
It really doesn’t matter how you do it
but you need to create internal engine heat to clean out the engine. This is
done with a load on the engine. If in neutral, it will take longer to create a
load and heat. In gear while underway will heat up the engine faster.
This is true for all diesel engines.
Where you run the RPM depends on the
engine. Typically, 80% of max power will heat up the engine nicely without too
much strain. This is also good for the turbocharger, if fitted with one.
How long? At least every couple of hours
while underway, if not a little more frequently... We run ours up every hour
for about five minutes. This works for us.
Keep in mind, this is not just the
ship’s engine but also true for the genset. Running a genset without load will
cause carbon buildup. Keep the genset loaded when charging batteries etc. We
find it best to run a couple of AC units or do a load of laundry etc. The
battery charger only puts load on the genset at the beginning of the charge
cycle.
Hope this helps.
With best regards,
Mark
Skipper
Sailing Vessel - Cream Puff - SM2K - #275
Currently cruising - Curacao
www.creampuff.us
Ok. Bullshit aside.
I
do have a few real questions, that I’ve had for a while.
It’s
the same for all diesels. Yes?
Is
“racing” out of gear best? I would think load would be required to
increase fuel consumption and thus heat. Fuel burn>>heat dissipation 2/2
raw water flow.
Forget
the rpm. Where is the throttle? 100% down? 80%?
Many
thanks, as always to this great group.
Bob,
Wow! Sorry. I didn’t realize I had to be
so freaking specific. Seriously! The essence of the post I made is 100%
correct. I didn’t intend to make a verbatim quote of the manual. If I
had, I would have used quotation marks. I stated this is OUTLINED in the
manual. I did not say this is a DIRECT QUOTE from the manual. Geeez! And,
please note I did say 4JH4 manual, not 4JH3 as you are quoting.
But if you want specific details of the
JH4 Operation Manual, publication number OAJH4-G00102, page 78. I quote,
“Periodically operate the engine near maximum speed while underway. This will
generate higher exhaust temperatures, which help clean out hard carbon
deposits, maintain engine performance and prolong the life of the engine”
This is below the section you quote
about running it in idle and speaks specifically about running the engine while
underway.
Regardless of whether this is done in
neutral or in gear while underway, the purpose of the procedure is to raise the
internal temperature of the engine periodically to remove carbon build up.
Carbon build up will kill a diesel engine.
I’m feelin’ a little crabby today. Can
you tell?
With best regards,
Mark
Skipper
Sailing Vessel - Cream Puff - SM2K - #275
Currently cruising - Curacao
www.creampuff.us
Hi Mark,
Regarding
"Running a lower RPMs without load will shorten the life of the engine
unless it is pushed up at least once per hour for about 5 minutes. This is
outlinede in the Yanmar operation manual."
This
is not to challenge the veracity of your statement but I cannot find that in my
Yanmar manual. Maybe you have a different manual and it would be helpful
(really) to have you quote what it says.
What
my 4JH3-HTE Operation Manual says (on page 30 section 4.6) is:
"When
operating the engine at low speed ffor long periods of time, race the engine
once every 2 hours"..."Racing the Engine, Morse Remote Control Handle
Pull out the handle lever...and shift the engine speed from high to low several
times...Racing the engine removes carbon built up in the compustion chamber
around the fuel injection valve. Neglecting to race tthe engine will
cause the exhaust to turn black and lower the efficiency of the engine".
In
other words it says to gun the engine several times while it is in neutral.
Like
others, we vary my speed between 1600 and 2200 for cruising and can cruise up
to 2400 rpm. We also run it at say 2800 for 5 minutes or so
periodically. However, I cannot find where Yanmar recommends this.
There are postings in this group (not yours) that say to run it full out for 5
minutes, even full out fo 30 minutes but I don't think that is advisable. Seems
that vibration is higher and it might be hard on the transmission and c drive
as well. Like most of us we vary the speed and run it harder at times but
we also do the "Racing" procedure that is in our manual.
Bob
and Suzanne, KAIMI #429
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