Reply
 
Thread Tools Search this Thread Display Modes
 
Old 01-08-2017, 02:56 PM   #1
keb
Senior Member
 
keb's Avatar
 
City: Portland, OR
Join Date: Nov 2013
Posts: 150
Newer generation engines

Quote:
Originally Posted by Hobomack View Post

In our experience, reinforced by the advice of a major engine manufacturer, the current common-rail electronically-controlled engines in this size range are not prone to "carboning up" from uncombusted fuel because the fuel is metered so precisely to meet the power demand -- the concerns associated with operating a mechanically-controlled diesel at low demand are not applicable to the current generation.

Scott Helker
Helmsman Trawlers

I didn't want to hijack another thread regarding someones beautiful new boat delivery .... just a question. For those of us who are not diesel experts, when did the common rail electronically controlled engine become the standard for marine application? If one was looking in the used market, AND wanted to search only for boats that had this newer generation, what year would you start at? Or is there an easier way to identify these engines through model numbers commonly referenced on yachtworld?
__________________
Advertisement

keb is offline   Reply With Quote
Old 01-08-2017, 03:26 PM   #2
Guru
 
Join Date: Apr 2014
Posts: 1,288
I can not give you a year but most used boats are pre common rail. You would be looking most likely at a used boat five or less years old for engines with common rail. The technology is more pertinent to new builds and very recent boats. When I had my custom boat built in 2011 CR engines were readily available. Most of the boats on this site maybe( 95%+) do not relate to the common rail technology. If the boat has it and all the electronics are doing their job it makes a significant difference in how you can run your boat. You can even design a boat around the concept of multiple sweet spots of speed and my boat is exactly that. An old school diesel engine would not like that concept while a CR engine is right at home with different load demands.
__________________

eyschulman is offline   Reply With Quote
Old 01-08-2017, 03:36 PM   #3
Guru
 
drb1025's Avatar
 
City: Bellevue, WA
Country: USA
Vessel Name: Fiddler
Vessel Model: DeFever 46
Join Date: Oct 2012
Posts: 607
My boat was built in 2010 and it does not have common rail engines.
drb1025 is offline   Reply With Quote
Old 01-08-2017, 03:37 PM   #4
Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Country: USA
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 5,354
The Cummins QSB and QSC were hitting the market around 2005 (???). These are common rail. And they really do not seem to mind light load running. Super clean burning.

Volvo D4 and D6 have been out for several years, not sure when exactly. Also common rail.

Some smaller random offerings from Yanmar and Volvo, but I would avoid those.

I was initially spooked by computer engines, both common rail or other type electronic controlled injection. But they have proven quite reliable. Not so spooked any more.
Ski in NC is offline   Reply With Quote
Old 01-08-2017, 03:59 PM   #5
Guru
 
tadhana's Avatar
 
City: New England and Canada to Florida
Country: USA EAST
Vessel Name: Tadhana
Vessel Model: Helmsman 38 Pilothouse
Join Date: Jul 2011
Posts: 573
Quote:
Originally Posted by drb1025 View Post
My boat was built in 2010 and it does not have common rail engines.
What engines do you have?

The common rail diesel fuel system was first developed in the 1990s as the engine manufacturers began to address the increasingly tight emission regulations here and in Europe. The emission regulations have been tightened over time and the engine manufacturers have met them with increasing sophistication in managing fuel, air and exhaust. Read computers all over the engine. In our 2009 Cummins QSB 5.9 there is a circuit board under the valve cover at each injector. Small diesel engines had been exempted but the lower limit has been slowly lowered and now many of the small sized marine diesels (100 hp) have to meet the emissions regulations. The latest marine engines must meet Tier 4 regulations.
tadhana is offline   Reply With Quote
Old 01-08-2017, 04:03 PM   #6
Guru
 
drb1025's Avatar
 
City: Bellevue, WA
Country: USA
Vessel Name: Fiddler
Vessel Model: DeFever 46
Join Date: Oct 2012
Posts: 607
Jd 4045
drb1025 is offline   Reply With Quote
Old 01-08-2017, 04:23 PM   #7
Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Country: USA
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 5,354
Deere has some of their engines now with common rail, but not all of them.
Ski in NC is offline   Reply With Quote
Old 01-08-2017, 04:25 PM   #8
Senior Member
 
BIG CAT's Avatar
 
City: Kiln,MS
Country: USA
Join Date: May 2016
Posts: 457
The use of common rail fuel systems varies from engine to engine and from one mfg to another. Cat only has 3 engines that use common rail fuel systems. Most all the others use cam shaft actuation with electronic control.
BIG CAT is offline   Reply With Quote
Old 01-08-2017, 04:28 PM   #9
Guru
 
tadhana's Avatar
 
City: New England and Canada to Florida
Country: USA EAST
Vessel Name: Tadhana
Vessel Model: Helmsman 38 Pilothouse
Join Date: Jul 2011
Posts: 573
This JD 4045 were probably previously under the displacement limit for the emissons regulations and the regulations did not aply to them. The lower displacement limit now covers most 4 cylinder engines.
tadhana is offline   Reply With Quote
Old 01-08-2017, 04:31 PM   #10
Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Country: USA
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 5,354
Cat has historically made their own fuel injection equipment while other mfr's buy theirs from Bosch, Denso, Stanadyne, etc.

When CR came to the market Cat may have gotten into a patent pickle. The probably could not make their own CR system without infringing. They certainly have been slow to adopt. I think the only smaller engines they offer with CR are built entirely by another company in the EU and painted yellow. I think some of their large engines are CR, but does not apply to this market.
Ski in NC is offline   Reply With Quote
Old 01-08-2017, 04:48 PM   #11
Guru
 
drb1025's Avatar
 
City: Bellevue, WA
Country: USA
Vessel Name: Fiddler
Vessel Model: DeFever 46
Join Date: Oct 2012
Posts: 607
Quote:
Originally Posted by tadhana View Post
This JD 4045 were probably previously under the displacement limit for the emissons regulations and the regulations did not aply to them. The lower displacement limit now covers most 4 cylinder engines.


JD now offers the 4045 with common rail.
drb1025 is offline   Reply With Quote
Old 01-08-2017, 05:06 PM   #12
Guru
 
djmarchand's Avatar
 
City: Litchfield, Ct/Punta Gorda, Fl
Country: USA
Vessel Model: Atlas Pompano 23
Join Date: Aug 2012
Posts: 4,829
Ski has given a good summary of who makes CR engines. But I want to challenge the premise that this whole thread is based. That is that common rail engines allow them to successfully be operated at light loads.

Let me paraphrase Tony Athens for the umpteenth time: "I have never seen a marine propulsion engine harmed by running at light load". He first said this before CR engines existed in the marine world.

Yes, I do believe that CR helps an engine to run at light load, but it isn't essential. CR pushes fuel through the injector tip at thousands of psi, not the hundreds (anyone know what it really is?) of mechanical engines so the fuel droplets are much smaller. Also some CR systems with piezo injectors operate with several pulses per combustion event so diesel is fed in a more controlled way into the combustion zone.

These features have had more benefits to emissions and quiet, smoke free running than on low load capability.

And CR does not have a big effect on efficiency. Ski posted an analysis he did on boatdiesel a few years ago comparing two Cummins engines of similar horsepowr, one a CR and one a modern mechanically injected engine- the QSC and the 6CTA I think. The mechanical engine was more efficient at some rpm/load ranges than the CR.

David
djmarchand is offline   Reply With Quote
Old 01-08-2017, 05:09 PM   #13
Guru
 
BandB's Avatar
 
City: Fort Lauderdale
Country: USA
Join Date: Jan 2014
Posts: 17,431
Quote:
Originally Posted by BIG CAT View Post
The use of common rail fuel systems varies from engine to engine and from one mfg to another. Cat only has 3 engines that use common rail fuel systems. Most all the others use cam shaft actuation with electronic control.
It's by manufacturer and size. MTU was the leader introducing them as standard on their 4000 series in 1996. With most manufacturers they started on the larger engines as the smaller engines were not subject yet to the same requirements.

All CAT Tier 4 engines will be common rail.
BandB is offline   Reply With Quote
Old 01-08-2017, 05:50 PM   #14
Veteran Member


 
City: Oxnard, Calif
Country: Oakview, Calif
Vessel Name: Local Bam=nks
Vessel Model: Custom 36Ft Wilson Sportfisher
Join Date: Nov 2008
Posts: 54
Low Speed Running

Quote:
Originally Posted by BandB View Post
It's by manufacturer and size. MTU was the leader introducing them as standard on their 4000 series in 1996. With most manufacturers they started on the larger engines as the smaller engines were not subject yet to the same requirements.

All CAT Tier 4 engines will be common rail.
My direct experience with CR engines ( since early 2005-ish) leads me to believe that they indeed do better than mechanical engines running at low power settings in relation to there max power ratings or HP used per liter of displacement..

The reason is simple--Each RPM/load setting can be better optimized as to all the things that affect proper combustion.. On a mechanical engine, all you can do is basically set the pump to maximum power efficiently and everything else is a best compromise.. Luckily mechanical fuel injection is well seasoned as to design and as noted, CR engines do not always show a better BSFC in many cases, but not all.... Recent advances in ECM design
has let to some decent BSFC efficiently gains in the mid-range HP power settings on the Cummins products, most notably the QSL9 and the 6.7 Tier 3 products.

Long term cruising at 10-15 HP per liter seems to have zero negative effects as I now have plenty of these engines in the field will well over 15000 hours and at least a have about dozen at over 20,000 hours now. Of course, some of these boats had mechanical engine that went 20,000 hours++at low power setting to in the 10 years before and they came out running good..

Time will tell, but so far so good.

Tony
__________________
Tony Athens
https://www.sbmar.com

"For All things Cummins That Make Sense & Cents"
Tony Athens is offline   Reply With Quote
Old 01-08-2017, 07:07 PM   #15
Senior Member
 
BIG CAT's Avatar
 
City: Kiln,MS
Country: USA
Join Date: May 2016
Posts: 457
Quote:
Originally Posted by djmarchand View Post
Ski has given a good summary of who makes CR engines. But I want to challenge the premise that this whole thread is based. That is that common rail engines allow them to successfully be operated at light loads.

Let me paraphrase Tony Athens for the umpteenth time: "I have never seen a marine propulsion engine harmed by running at light load". He first said this before CR engines existed in the marine world.

Yes, I do believe that CR helps an engine to run at light load, but it isn't essential. CR pushes fuel through the injector tip at thousands of psi, not the hundreds (anyone know what it really is?) of mechanical engines so the fuel droplets are much smaller. Also some CR systems with piezo injectors operate with several pulses per combustion event so diesel is fed in a more controlled way into the combustion zone.

These features have had more benefits to emissions and quiet, smoke free running than on low load capability.

And CR does not have a big effect on efficiency. Ski posted an analysis he did on boatdiesel a few years ago comparing two Cummins engines of similar horsepowr, one a CR and one a modern mechanically injected engine- the QSC and the 6CTA I think. The mechanical engine was more efficient at some rpm/load ranges than the CR.

David
as far as injection psi. its could be as low as 2k for a old pre-combustion chamber fuel system to 28k for the c175. the c175 is the only large common rail engine cat makes as of right now. the other 2 are the c4.4 and c7.1 and the top out at around 14k psi.

as for running at light loads. the only issue that typicality happens is slobbering. most all of the new(last 5 years) engines below the 3500 series have very little issues with slobber. the old stuff was a different story. the ring pkg(keystone's) didn't seal well below about 30% load. in a boat you probably would be running at or above that mark most time. but with standby generators we see it a lot. the 3304 and 3306 were notorious for high oil consumption we ran with light or no load. but if you loaded them up good and put some heat in the hole they had a normal amount of consumption .
BIG CAT is offline   Reply With Quote
Old 01-08-2017, 07:16 PM   #16
Senior Member
 
BIG CAT's Avatar
 
City: Kiln,MS
Country: USA
Join Date: May 2016
Posts: 457
Quote:
Originally Posted by BandB View Post
It's by manufacturer and size. MTU was the leader introducing them as standard on their 4000 series in 1996. With most manufacturers they started on the larger engines as the smaller engines were not subject yet to the same requirements.

All CAT Tier 4 engines will be common rail.

there are tier 4 final and tier 4 interim engine's out right now that are not common rail. they will remain that way for the foreseeable future. cat is working on common rail for some engine's but not all. my hope is trump can pull back the epa regulations to allow mfg time to develop the systems before they hit the market. imo the tech is not where it needs to be from a reliability and cost effective stand point.
BIG CAT is offline   Reply With Quote
Old 01-08-2017, 07:31 PM   #17
Veteran Member


 
City: Oxnard, Calif
Country: Oakview, Calif
Vessel Name: Local Bam=nks
Vessel Model: Custom 36Ft Wilson Sportfisher
Join Date: Nov 2008
Posts: 54
Marine emissions

Just an FYI............ This forum and thread is talking about MARINE propulsion engines in sizes applicable to boats generally in the 20-100 ft range, with 95++% of them in the 30-45Ft range. Tier 4I or Tier 4 final IS NOT applicable to any marine propulsion engines in this size range.

Let's not confuse what this is about with engine designs or emission certifications that are not part of what this is about. ------------MARINE CERTIFICATIONS for EPA Category 1 propulsion engines.

Tony
__________________
Tony Athens
https://www.sbmar.com

"For All things Cummins That Make Sense & Cents"
Tony Athens is offline   Reply With Quote
Old 01-08-2017, 08:19 PM   #18
Master and Commander
 
markpierce's Avatar
 
City: Vallejo CA
Country: USA
Vessel Name: Carquinez Coot
Vessel Model: penultimate Seahorse Marine Coot hull #6
Join Date: Sep 2010
Posts: 11,415
Common rail? Never heard of it before except when wiring my model railroad (operating on two rails) in the 1960s in 12-volt.
__________________
Kar-KEEN-ez Koot
markpierce is offline   Reply With Quote
Old 01-08-2017, 10:34 PM   #19
Guru
 
Join Date: Apr 2014
Posts: 1,288
I have had 4 seasons experience with twin CR JD 6068 at 330Hp rating. Most of the time they are run at low loads. I have even gone one step farther by under propping and at max rpm get no more than 80% load. The boat runs sweet with zero smoke at all speeds up to 19K+ and I have no worries about over loading. I consider my actions as a form downgrading the engines from recreational type 4 rating to something less without the chip. I know most on this site will not be dealing with CR engines but for those looking at boats with them I am with Tony Athens and tell you to ignore some of the old school negative hearsay. As a teen ager I was a hot rodder and it is plainly apparent to me that almost any family car with modern electronic motors run so much better than what I used to play with and CR appears to be a positive improvement.
eyschulman is offline   Reply With Quote
Old 01-08-2017, 11:11 PM   #20
Guru
 
twistedtree's Avatar
 
City: Gloucester, MA
Country: USA
Join Date: Jan 2013
Posts: 4,937
I've had nothing but great results from CR engines. They start right up, run clear all the time, minimal smell, quieter, smoother.... what's not to like.

My main is common rail (JD 6090), and the wing is not (JD 4045) with different tier ratings. I was confused why one engine needed to meet the then-newer EPA spec (I don't recall which one, but I think tier III), and the other didn't. So I dug into the requirements and its phase-in was based on the HP/liter rating on the engine. So higher output engines, as in higher hp/liter had to meet the new regs first, followed by lower output. This generally translated into pleasure rated engines first, and continuous duty engines later. My 6090 triggered the requirements at around 35hp/liter, but the 4045 didn't at just under 20hp/liter, hence the difference.
__________________

__________________
www.MVTanglewood.com
twistedtree is online now   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 09:51 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012
×