Threaded Mode | Linear Mode

2Nickels

Recently I had my stop engine light come on shortly after starting my engine. This led to a roadside repair in which I had to replace both the Turbo and Actuator. This is my second Turbo in 10,000 miles and I am looking to figure out why, what I need to prevent needing another on in a few miles and what I should be watching for.

The background on this is I have a 2009 Motorhome with a 2008 Cummins ISX 650. The engine has 55K on it and was entirely rebuilt at 23,000 miles due to the fact it had sat for a # of years along with a dropping valve matter on #6 I felt it best to rebuild the engine. At 45,000 miles the engine needed a Turbo and Actuator, then again at 55,000 miles.

Ahead of the stop engine light appearing I was driving and everything was running fine. The
"Hot Exhaust" light had come on and remained on for about 30 minutes. This was on while I was driving and I continued to drive the coach as I have done a number of times. Shortly after the light went out I pulled over for a break and when I pulled over I shut down the engine. The "Stop Engine" light appeared when I restarted the engine.

When the techs were installing the new turbo they commented that my tailpipe was very black/carboned up. I don't know what this means.

Any help/suggestions I can collect from the forum users is appreciated.

Rawze

the "hot exhaust" light means that it is doing a "regen" cycle... the exhaust and turbo and everything is going to get really hot.

If somebody shuts off the engine while its still really hot, it can cause serious damage to the turbo and/or its actuator. The oil flow and coolant flow suddenly stops and that 800+F temps on the manifold and housings will soak into the electronics and the turbo, carbonizing the bearings. It is a common problem, especially given the fact that most people who own newer equipment do not know any better.

IF SOMEONE SHUTS THE THE ENGINE OFF while the exhaust was still cooking hot due to a passive regen cycle, then that could be a major contributor of the problems that were described.

Also... With a suspected pre-mature turbo or other major component failure... SOMEONE NEEDS TO FIND OUT EXACTLY WHAT FAILED, and stop allowing mechanics throw parts at it. This especially on an expensive component like a turbo or actuator. Otherwise, a person will just keep throwing endless amounts of $$$ money at problems to no real avail.

- WHAT SHOULD HAVE HAPPENED .. When it failed the first time, if it was a pre-mature failure, ... is that the turbo/actuator should have been sent to someone like YTS turbo in griffin, GA., or some other high-end turbo shop so that it could have been inspected to see exactly what inside it failed. This almost always leads to the actual possible causes of WHY!

Your post hints heavily towards shutting it off with it too hot + maybe neglect from not running and servicing the engine enough?. But so far but it is anyone's guess, just from reading your post.

=====

(A personal rant and observation in general about RV's ) ..

THEN THERE IS THE "RV" FACTOR TO CONSIDER OVERALL TOO ...

Plain and simple... I am not a fan of these commercial engines being used inappropriately in RV's. Some of it can be blamed on the manufacturer, and some on the owner. - MOST ALL OF THESE TYPES OF "confined spaces", inappropriate shifting points in the "auto-Shitter" trannies they usually have in them, Owner/driver not knowing squat on how to properly drive the engine for longevity, not knowing squat on how to properly care for them, and all sorts of other abuses that happen. Combine this with VERY inappropriately geared drive trains, and some horrible need to make the engine waaay-Overpowered because of horrible drive-train and tranny designs, horribly geared for the application, so that it can be lugged into an agonizing, short-lived death its whole life, lugged below 1500RPM where this is an abuse of all its own!.

-- Most RV owners have no clue how to properly maintain one of these commercial engines that is meant for a truck. Neglect in several ways run amuk!. Most Don't actually do much past changing the oil on them, just like they would a typical car engine, not doing any kind of actual regular preventative maintenance to them.

I.E.> No tune-up work, not running them each week or so until fully warmed up to prevent "lot-rott" and rust, letting them sometimes sit for years at a time ... NOT changing the oil based on time, hours, and other factors.. but only on miles alone (which is also the kiss of death of one that sits a lot), Letting the whole engine get moisture buildup in it, Not replacing sensors yearly, or taking things apart to clean them, like the EGR, or emissions systems on them on a regular schedule, etc. etc.etc. - and all sorts of other abuses from severe neglect.

Most RV's have those god-forsaken Auto-Shitter, engine abusing tranny in them + too tall of rears to boot .. That combination of components is hell bent on running the engine in as low rpm and high torque applications as it can. THIS IS PURE ENGINE ABUSE! Especially for an ISX. to make things worse, The driver/Owner is not smart enough to keep the RPM's above 1500 in a pull, or when a lot of throttle is needed, by overriding the tranny, or is clueless and tries to keep the RPM as low as possible like complete fool... running the thing down the roads at the lowest rpm they can torture the engine with.. etc.etc... == ENGINE ABUSE AND ENGINE FAILURES!. That ISX enigne needs to see 1500-1900 rpm's when pulling and a lot of throttle is needed. Most those RV"s are spec'd so goddamn horrible, most of them will never see more than about 1500RPM and then wonder why the engine ate its own guts out!.

NOW ... TO ADD EVEN MORE INSULT TO THIS!!!...

MOST RV OWNERS (and even the manufacturers are guilty of this, because more HP sells for more moneys) WILL GO ABOUT MAKING SURE THE HORSEPOWER SETTING/RATING IS AT RIDICULOUS HIGH LEVELS vs. the severely confined spaces, only fan cooled, etc.. horrible air-flow for the engine compartment and engine .. .. AND THEN WONDER WHY THERE HAVE REPEATED ENGINE FAILURES AND ALL SORTS OF OTHER "HOT-ENGINE" RELATED PROBLEMS THAT ARE ONLY SEEN IN RV'S (that stupid chordal valve problem from years back, only seen in RV's, that they keep talkin about in their echo-chamber world) , THAT IS NOT SEEN IN THE COMMERCIAL TRUCK APPLICATIONS.

This all while blaming it all on the engine and not the person who set the HP (or allowed it to be set) higher than the poor/confined application air flow/ only fan-cooled, etc. can reasonably handle.

-- I TEND TO BLAME THE OWNER .. for not knowing any better.. AND OR BECAUSE SOMEONE, SOMEWHERE ALONG THE CHAIN OF THINGS WAS HE#LL BENT ON MAKING THE ENGINE AS MUCH HP/'TORQUE AS THEY CAN because they are not smart enough to realize that this is flat-out torturing engine abuse as it is.. and they seeming just want to have nothing but problems?.

To sum it all up ...
The crux of most RV engine problems with these commercial engines.. CAN BE FOUND ... by its owner (and these manufacturers) looking it the mirror!.

The real question is what is the owner fundamentally going to do about it?. The manufacturers obviously don't give a damn about you, or the application, beyond selling that "big power" and "can go 80+ mph down the freeways like an idiot factors .. To them, that is what sells ... "climb that mountain at 75MPH in top gear.. that is how we abuse our engines! .. factor! .. And these RV owners are dumb enough to buy into all this garbage!. That is why they are spec's so horribly to begin with, won't go past about 1500RPM on the tranny without dropping it back to 1100, so that it can beat the liners out of it every time you do drive it!. AND THEN you got IDIOT OWNERS WHO WANT IT TO DO EVEN MORE.. AND MAKE IT ALL WORSE!.. Instead of turning that engine back down to what it can safely (back down to the 450HP/1650trq range) and reliably handle such confined environments + re-gear the RV so that it can go 63-65~ish at 1500-1600RPM's and have that goddamn Autos$it-box-tranny re-programmed to allow it to run above 1500, in the 1500-1900 range when actual pulling is needed!. - Guess WHAT!!>>> MOST OF ALL THEIR PROBLEMS WOULD BE SOLVED IF THEY ACTUALLY DID THIS!!... But Who am I but just some idiot making a rant, no one cares.

2Nickels

Rawze, I appreciate reading your thoughts that turning the motor off before allowing the system to cool down is likely the cause of my damage. Would it be best to install a Pyro to be able to see the exhaust temperature? What is a safe temperature to shut down the engine?

Your comments about RV's is interesting. I too feel many don't drive their RV's properly and treat them cruising in a Cadillac (so to say). In my case, I do watch my RPM's and work to keep the the power/torque band best as possible to ensure there is no lugging of the engine. It's not as simple as it may be with more gears to chose from but either way I work the driveline.

Rawze

(12-06-2021 )2Nickels Wrote: Rawze, I appreciate reading your thoughts that turning the motor off before allowing the system to cool down is likely the cause of my damage. Would it be best to install a Pyro to be able to see the exhaust temperature? What is a safe temperature to shut down the engine?

Your comments about RV's is interesting. I too feel many don't drive their RV's properly and treat them cruising in a Cadillac (so to say). In my case, I do watch my RPM's and work to keep the the power/torque band best as possible to ensure there is no lugging of the engine. It's not as simple as it may be with more gears to chose from but either way I work the driveline.

If you install a pyro on the outside of the manifold, like in my viodos about installing gauges shows, so that you can monitor the manifold temps and not the exhaust temps themselves.. .. Then you can see when it is safe to shut the engine off. When the manifold temp is below 300-F or so, its safe to shut off the engine. .. andif the manifold is getting upwards of 950+F in a hard hill climb, etc.. .. Then it is time to back out of it, slow down, use a lower gear and higher RPM's to move more air thru the engine to cool off the engine, turbo, and exhaust systems.

JimT

(11-29-2021 )2Nickels Wrote: When the techs were installing the new turbo they commented that my tailpipe was very black/carboned up. I don't know what this means.

That depends. If they are talking about the section of pipe immediately connected to the turbo then that's somewhat normal. If they are talking about the very end of your tail pipe then that's bad. On a 2008 engine you have a DPF that collects the soot. This is what needs to be "regen'd" periodically when too much soot has built up. If soot is making its way past the DPF and out the tail pipe then your DPF or DOC might be no good. IF the DOC and/or DPF are no good this could also be affecting the turbo.

On the engine side of things, if the pipe post tubro is collecting an excessive amount of soot then you could have moisture in the exhaust, possibly oil or coolant (could be from the engine or at that location it could have come from a failing turbo too), OR you could have a problem with the "7th" injector, AKA the dpf doser injector. This part, located just after the turbo, injects fuel into the exhaust stream during DPF regens. It's how the system is able to raise the DPF temp high enough to burn off the collected soot. If this injector is leaking then it could be the cause of the excess soot build-up. It would also slowly coat the DOC and DPF with fuel, degrading their performance and lifespan, clogging up the filter and reducing exhaust flow (thereby increasing back pressure on the turbo) as well as eating/washing away the precious metal coating on the DOC which is needed to create a catalytic reaction during a regen.

Finally, you could have an engine issue creating excess soot in the exhaust. This in turn leads to DPF clogging, excessive backpressure, frequent DPF regens and lots of extra stress on the system (including the turbo). Maybe a sensor reading incorrect, a bad/sticking EGR valve, failing EGR cooler or some internal engine issue. Most likely it just needs an "EGR tuneup" (that's a Rawze term, search this forum and youtube for more details, instructions and videos). Simply put, replace common sensors, clean soot buildup from the EGR and air intake systems and clean any buildup from the dpf doser injector.

The above are all possible contributing factors to your turbo failures. More investigation would be needed to narrow down actual factors. Best bet is to start with an EGR tuneup. Make sure the engine is able to run at its best. Then work your way back. You can disconnect the exhaust pipe from the rear of the turbo and run the engine to visually check soot level. Also, hold a piece of paper in the open exhaust stream to check for the presence of any kind of liquid (coolant or oil) in the exhaust. Inspect the DPF doser for leaks and soot buildup. These are good starting points.

search through the forum, there's tons of dpf, doc and egr related info on here. You'll find plenty of ppl on here willing to help you, as long as you're willing to help yourself.

JimT

(11-29-2021 )2Nickels Wrote: The "Stop Engine" light appeared when I restarted the engine.

Did they read the active and inactive codes and tell you what they were? It would be helpful if we knew what codes were present at the time this happened and exactly which code triggered the stop engine light. I know, it's probably too late to ask, but that's the kind of info that helps.