My 1993 U225 with the Cummins 5.9 recently failed the Arizona emissions test. They only look at opacity. The standard is approximately 30; my engine read 63.
A Cummins service company here in Tucson asked how many miles I have on the engine; about 202,000. He asked if I had ever had it rebuilt; no (I seriously doubt that I need a rebuild). He then told me that the 5.9s were not rebuilt anymore; just changed out.
I did have some major work done on the road in 2019. A broken timing gear cover turned into a big job. I also had the exhaust manifold replace about a year ago.
Another diesel mechanic (small family business) suggests that I may just need to service the engine; oil, filters, fuel filters, air filter, etc., and/or replace fuel injectors. He is going forward with the service; we'll see how the opacity reads after that.
Any comment/suggestions?
Roger
Others much more knowledgable than I will comment I'm sure.
I would guess that of the things listed by the mechanic to replace, the only ones that might improve your tailpipe emissions are the new injectors and new air filter. If they are really "worn out" then your air/fuel ratio may be off, causing more "smoke" out the tailpipe. Like I said, this is just a armchair guess on my part.
Have you considered moving to a place that does not require diesel emission tests? 8)
First thing I would do is run some injector cleaner through it.
Then push the engine HARD to plow out as much soot as you can before being retested.
Agree on doing the routine PM part of what was suggested.
Clan oil and filters never hurt, and if you have too many particulates i.e., in the modern idiom you're "Rolling Coal," then having the fuel injectors serviced may be just the thing you need. One injector feeding more than another, or a poor spray pattern does affect combustion.
If someone has turned up the fuel pump for more power that could effect the test. A lazy turbo could also be a factor. Take Brett's advice first as that is the cheapest and requires no mechanical work.
As others have suggested, change oil, new air cleaner, injection cleaner and then drive the devil out of it. Sounds like you had the dreaded timing cover pin come out and it destroyed the timing cover. People rebuild Cummins B engines all the time. It is a parent bore engine so no liners but has a B50 life of 350K miles. Not ready for overhaul in most cases. No liners makes it a little more expensive as it has to be bored. Tons of parts available but Cummins is saying that the prices they charge per hour make it more economical to exchange the engine
You could also install a diesel CAT (converter) to drop the emissions. Go to a non factory shop that works on Cummins and ask plus go to a B engine forum and poke around. CAT options here: Catalytic Converters for Ram 2500 for sale | eBay (https://www.ebay.com/b/Catalytic-Converters-for-Ram-2500/33629/bn_19595989)
Pierce
How warm was the engine when you tested? Like Brett said put the amount of injector needed for the amount of fuel in your tank and run hard just before the test. My '81 makes a world of difference between warm and hot on the smoke.
As Racedad says, if the main injection pump has been turned up, it will smoke more. Your model may have the Bosch inline P pump. If so, check to see the top slot has not been filed to give more travel for more power. I can remember in the old days that many owners would do that.
Pierce
Pretty sure your U225 didn't come with a CAT so here is a weld in model for $230 plus shipping: Dodge Ram 5.9L 2500/3500 Diesel 2003-2006 OEM weld in Catalytic Converter | eBay (https://www.ebay.com/itm/Dodge-Ram-5-9L-2500-3500-Diesel-2003-2006-OEM-weld-in-Catalytic-Converter/254202980013?hash=item3b2fada6ad:g:K9UAAOSwBY1bW4uk)
Pierce
In checking pumps for your engine, it appears you have a VE pump so no slot. The P.O. may have installed a power pin: DDP First Gen Power Pin (https://www.xtremediesel.com/ddp-first-gen-power-pin) Is it possible to contact them?
Pierce
Engine temperature was 185-190F during test.
Service to be done tomorrow. Then I'll run some injector cleaner through it and see how it checks out. I don't think I can get the temperature over about 190F, unless I can hook up a heavy trailer and find a steep hill to climb.
Thanks to all for the input. I'll post results as they come.
That 190F is the regulated temperature and is exactly how hot the engine is supposed to be. What you need to make hot is the exhaust system, so a 25 mile run on the highway, "on your way to the inspection station" to burn out any loose fluff in the exhaust pipes is your goal.
If all else fails,take a ride on that airhead and spend one night in South Dakota,then you can register it there,that's one reason you see all of their plates.
I noticed my previous Cummins smoked alot when starting out from a stop. I started using this Power Service Products product, and it immediately ended the black smoke after 25 miles. If it is posible, I would run this product before your maintenance service, and then drive at least 25 miles on the hwy. "It is the only product recommended by Cummins."
"DIESEL KLEEN +CETANE BOOST
A total injector cleaner and performance improver.
Diesel Kleen +Cetane Boost is loaded with cetane, detergent and lubricity improver to provide peak diesel performance."
"80-OUNCE (PART NO. 3080)
Add entire contents (80 ounces) to 250 gallons of diesel fuel. For maximum cetane boost and quicker fuel injector clean-ups, add entire contents (80 ounces) to 125 gallons of diesel fuel."
I have used the product ever since. It is available at Walmart in the larger 80 ounce size. If posible put the right amount of additive in your tank for the amount of fuel in your tank. As I remember the instructions say adding up to a certain %, posibly 50%, over the recommend amount is ok. I would follow the Power Products product instructions.
Diesel Kleen +Cetane Boost - Power Service (https://powerservice.com/psp_product/diesel-kleen-cetane-boost/)
We use it at every fillup,they also have a size that can do 1250 gallons,Fleet Farm has that size.
Another thing that will cause smoke is a leak in charged air cooler system. Check the hoses, connections and any cracks in the CAC itself.
A loss in power comes along with that but if it's gradual you might not notice it.
I use Diesel Kleen and have had good results. It's not an instant thing so best to add to fuel and then drive it. The more miles, the better.
Cetane rating is just the opposite of octane. The higher the cetane rating is, the easier the diesel explodes and a more complete burn is achieved. Cetane number - Energy Education (https://energyeducation.ca/encyclopedia/Cetane_number)
Pierce
And what Pierce failed to add was that low Cetane numbers contribute to knocking, because the knock in a diesel engine is a sign of delayed ignition.
Sorry you are having a registration problem.
Try getting tested after a couple of hours on I-17 working hard on hills to get everything very warm.
Also try to limit how far full throttle pedal opens throttle, to reduce max testing RPM.
Keep maint receipts to show you have made changes to improve things.
Is this a new coach to you or are you new to AZ? Where was it registered before?
Barry,
I'm in Tucson, so I'm quite a ways from I-17. I've owned the coach for about 9 years; the two po's also live here in Tucson. So, the coach and I are long-time Arizonans. This is the first time I've had a problem with emissions on the coach. The test here in Tucson for diesels is to run the coach on the dyno at 50 mph; so, not running at full throttle. I think this is a fairly new method. If memory serves, the last emissions test was done at 35 mph.
Roger
Roger they have been doing a similar test on the diesel pickup trucks in Nevada for years. 50 mph and load to 15hp. Few fail. Hope we never see MO tested
Scott
Are you sure that your location requires emissions inspection? Our address does, but friends a mile away do not.
ADEQ: VEC Address Locator (https://gisweb.azdeq.gov/arcgis/veiareas/)
"Emissions test required" shows on my renewal notices; and our zip code is in the Tucson metropolitan area requiring testing.
Update:
Had the normal service performed: oil, filters, etc. Then put a bottle (80 oz.) of Diesel Kleen in the tank with close to 100 gallons of diesel and ran the p-waddin' (my mom's term) out of it; about 40 miles at approximately 70 mph. And straight to the emissions station. Opacity dropped from 63 to 2.9; yep, 2.9. Amazing. Good for another year.
Thanks to all for the input/advice.
roger
Good job!!! Nice to have your checklist.
And you can see why I used a diesel additive before taking the cars from the boat to the lab. Can't afford to fail a $2000 test. Additives DO WORK.
Pierce
Thank you for reporting back great results and another tool for the box.
Amazon.com: Power Service Diesel Kleen + Cetane Boost - 6/80oz. Bottles:... (https://www.amazon.com/Power-Service-Diesel-Kleen-Cetane/dp/B00MG04HII/ref=sr_1_5?crid=9ZNGC5KOH1IB&dchild=1&keywords=diesel+clean+fuel+additive&qid=1616181969&sprefix=Diesel+clean+%2Caps%2C233&sr=8-5)
Scott
Thank you for documenting this. Those of us with non computer engines may need to prepare for the possible rule changes in California.