Have noticed a puff of black smoke when starting up from a stop lately and at idle the exhaust stinks. It's getting worse. Today drove 150 miles, some of it in the mountains and when pulling into town, it smoked at each green light after a stop. Background: Engine ISM450 with 88,000 miles, oil changed 300 miles ago, fluid temp/levels all good, air sensor in the green, idle is set at 650rpm, no turbo blanket, OEM muffler, altitude 3500' or so. Any ideas? Valve adjustment due? Woody.
I would dump 2 quarts of Diesel Kleen in the tank first.
You could have an air leak in the piping from the turbo through the inner cooler up to the intake. Look for a bad plenum connector hose. With that few of miles I would think something other than the turbo unless it has ingested something from a bad air cleaner. It would be good to check your valves especially for being too tight. Which on that engine isn't that big of a job.
If you were pulling in the mountains did it seem to be lacking in the power department?
Mike
Pull the intake hose off the turbo and take a look at the blades. Are the edges of them eroded away? If so you have some dirt ingestion, find the source. In addition recommend checking for exhaust leaks at manifold to head connections, base of turbo where it bolts to the exhaust manifold. Exhaust leaks in this area will have a major effect on turbo boost. One thing that can help locate these leaks is to view manifold/turbo base when someone cranks up the engine from cold. Best done from above with the bed securely propped into position! Do you have a stock muffler or a resonator?
Running at altitude is quick to reveal restrictive fuel filters, might be a good time to change them.
Thanks for the replies guys. I put 2 quarts of Diesel Kleen at last fuel up 300 miles ago, and it is a stock muffler. I'll check all the items mentioned in the next few weeks, fuel filters less than a year old, and will order a new air filter as I think this is at least 10 years old.
Black.smoke generally means overfueling until the engine reaches an equalibrium rpm/load. Are you synthetic oil, it help keeps turbo bearings from coking up and dragging. Thermostat stuck open may not let engine get hot enough to fully burn fuel.
Think I would check that 10 year old air filter.
I somehow missed that. Pull that antique out and discard, hopefully it's only plugged and not breached.
Dino oil. Temps are normal and cooler/fan is working okay. New Donaldson air filter on order. I'm leaning towards a resonator replacement for the muffler if anyone thinks this would help.
The resonator will make your turbo spool up much faster, this helps prevent smoke when taking off from a stop at altitude. Well worth it, lots of statements that they increase hp and mpg, can't comment on that. They sound boss.
If you have any other filters that are as old as the air filter,please change them whether they need changing or not.
Seems like some of the Cummins engines had a bypass relief valve for fuel overpressure back to the tank that was trouble prone.. If it's blocked it may overfueling.
All diesels with tank return lines have a pressure relief valve in the fuel system. Bosch P series may have it on the back side of the main injection pump. Not likely that it is plugged as it's a steel ball held against a seat by a spring. The problem they sometimes have is leaking into the return line and not allowing enough pressure in the body of the injection pump. This can cause partial fuel starvation and loss of power as well as causing premature wear to the pump. The fuel filters will keep harmful particles and algae out but seen through a microscope, tiny valleys get worn on the ball and the seat. Pretty easy to replace.
Here is a sample of what they look like: cummins cups pressure relief valve - Google Search (https://www.google.com/search?sxsrf=ACYBGNSHRC9ZIDjclXLkYplTys36eP5LMA:1569161596461&q=cummins+cups+pressure+relief+valve&tbm=isch&source=univ&sxsrf=ACYBGNSHRC9ZIDjclXLkYplTys36eP5LMA:1569161596461&sa=X&ved=2ahUKEwjRmbW8zuTkAhUKlawKHcC0BJMQsAR6BAgGEAE&biw=3170&bih=1657)
Pierce
Also check pressure from lift pump. They have a fairly high incidence of partial or total failure. Low pressure may cause one or two injectors to overfuel while the others have limited pressure.
P
Thanks, y'all. I'll check all these things you guys have recommended. Getting a new Donaldson air filter put in next week as well as took the turbo blanket and resonator plunge. Will test drive afterwards in a week or so, and report back. Woody.
You will be so excited you might not be able to type a response until you stop drooling...might be a while..