Diesel Particulate Filter Not Regenerating

[Ted and Fran Klimowski]

Traveling on I-75 in southern Ohio, our 2008 Beaver Contessa with a 425 Cat started slowing down, check engine light came on and the aspirator icon appeared on the dash.  Speed kept dropping until the engine final said shut down, right in the construction area of the x-way.  

After arranging to be towed in we are now at the Freightliner Service plant, closest business that said they could service us.  After running computer diagnostic a new fault came up - Mass Air  problem.  Whatever that means.  

Anyone have any ideas or experiences?

Ted and Fran Klimowski, tklimowski@comcast.net

[Wayne Baumann]

Yes, their are about 20 other rigs that have the same problem, and have been working with Cat. Will try to send you a contact tomorrow.

Wayne Baumann

[Wayne Baumann]

Ted,

Email Gil at:

trawlergil@comcast.net  about the engine problem.

Wayne

[LEAH DRAPER]

There is a google website with all the latest information from others experiencing the same or similar problems.
 
See:  http://groups.google.com/group/cat-c-9-community/topics.

Leah

[Richard And Babs Ames]

http://www.catrvclub.org/

The Cat RV Club has a yahoo forum and some contact numbers for CAT that may be helpful.

[Richard And Babs Ames]

Call the cat rv hotline. 877-777-3126
Sent from my Verizon Wireless BlackBerry

This was sent on the CAT RV Club Yahoo Forum

[Larry Fisk]

Is this an issue on my 2005? I haven't heard of this one before...

[LEAH DRAPER]

MY UNDERSTANDING IS THAT IT ONLY AFFECTS THE 2007 ON ENGINES.

[Richard And Babs Ames]

The engines built to the 2007 emmission standards have a particulate filter that filters the diesel ash from the exhaust gases and then burns the ash up to clean the filter. Engines built prior to the 2007 emmission standard do not have the device. The heat output of the exhaust when the particulate filter is burning required exhaust redesign.  

Effective 2010 even stricter emmission standards were effective and CAT made the decision to stop production of over the road engins instead of trying to meet the new emmission standards.  

[Gil_Johnson]

Ted,

You should have just received an invitation to join the Google group.  Although your specific symptons seem to be different than the problem many of us are having with the 2007+ engines, you may want to review the information in group site to see if you should be included in our discussions with CAT.

Richard,

You are correct that the 2010 emission standards are stricter.  The good news is that the engine manufactures had more time to design their engine systems to be compliant.  Almost all 2010 diesels use a urea based fluid to reburn the soot.  CAT used diesel reburner on the 2007+ engines.  These fluid injection systems are not new as I believe Mercedes has used them for years.  CAT has also made a commitment to enter the over the road market again, this time with their own truck that's jointly developed with Navistar.  That seems like a strange courtship given they are engine competitors.  Anyway, we'll see how this plays out.

Gil

[Larry Fisk]

Ok, thank you for the explanation. That explains the upset truck driver at a Flying J truck stop I was at. He was asking for the urea additive for his truck and they were out of it. He was not happy....

[LEAH DRAPER]

If Urea can be purchased at truck stops, I am "assuming" that must be doing something good for the DPF.  Pardon my lack of knowledge, BUT do they add it to the fuel??  Or WHAT?  Have any Beaver C9 owners ever done this?  Has it helped with the DPF problems that some have had thus far?

Leah

[Gerald Farris]

Urea is used in all U.S. highway HD diesel engine emission systems except the ones that are built by Navistar. The urea is used to control NOx (oxides of nitrogen). The reason that Navistar does not use urea, is that their system uses EGR (exhaust gas recirculation) to control NOx.

The urea system has it's own storage tank and injection system to spray a very fine mist into the exhaust stream where it releases ammonia that combines with the NOx to produce nitrogen and water vapor to harmlessly exit in the exhaust.  

Urea is not used to benefit the DPF system, but is used for NOx control. So if you are considering adding a urea injection system to help your DPF, don't.

Gerald

[Gil_Johnson]

Gerald is right on.  I doubt one could be added anyway given the fact that the engine's computer would have to command the urea injection system.  I'd add that altough not specifically intended to aid the DPF, I understand that urea injections systems don't have the diesel fired DPF cleaning system.  I could certainly be wrong, but I thought that's what a Cummins Rep told me as we looked at the rolling chassis at the Hershey RV show.

Gil

[Gerald Farris]

Gil,
The urea or DEF (diesel exhaust fluid) is injected into the exhaust after the DPF (diesel particulate filter) on all of the systems that I have seen and therefore can not help in regeneration of the DPF.

There are several methods used to regenerate the DPF. The most common one is the injector and igniter in the exhaust located right after the turbocharger, however some engine makers have learned how to use the injectors to supply a short burst of fuel on the exhaust stroke to elevate the exhaust temperature enough to cause regeneration. "Passive regeneration" can also be achieved when the engine is under a heavy load and the exhaust temperature is elevated, and EGR can be reduced to increase exhaust temperature since the increase in NOx that will occur with less EGR will be corrected by the urea system. But however the manufacturer accomplishes regeneration, it is not with urea directly.

Gerald