Soot in overflow tank

[miker61002]

I had a leaky EGR cooler, and I was going through about 1/2 to 2/3 gallon of coolant per day (roughly 500-600 miles). The EGR valve was also replaced. Flushed the system and recharged. The mechanic noted soot in the overflow tank, and, even though there are NO external leaks visible, I'm still using coolant. Does anyone know what my issue could be?

The truck SEEMS to be pulling O.K., but, under 30 psi or so boost, I can hear a slight whine (kind of like the ignition noise 4-wheelers in the 70's had). The oil doesn't show any coolant contamination (by sight or smell).

Engine data No: 79229273 Family: 6CEXH0912XAH CPL 8519

TIA.

Michael

[tree98]

This an 870,871,2350, or X15?

[marek4792]

(07-13-2020 )tree98 Wrote:  This an 870,871,2350, or X15?

Pretty sure that's an 870 CPL

[Waterloo]

Drop the pan and check the liners for coolant... An 870, it may be that time.

[tree98]

1/2 - 2/3 gallon of coolant a day is a lot. You would definitely see that in the oil. If your burning it you should see it in the exhaust since you don't have a dpf(cm870) to gobble the smoke. You gotta have some other symptoms ?? There's only 3 places it could go, in the cylinder and burned, in the oil, or on the ground.

[miker61002]

(07-13-2020 )marek4792 Wrote:  

(07-13-2020 )tree98 Wrote:  This an 870,871,2350, or X15?

Pretty sure that's an 870 CPL

Yes, it's an 870. The mechanic that did the R&R on the EGR Cooler said the system might be thirsty for a little bit until I work the motor hard enough to open the T-Stat...I did about 450 miles on the I-81 today, so I'll see what it looks like after being off all night... will advise.

[Waterloo]

Have you inspected the crankcase filter for contamination?

[tree98]

(07-14-2020 )Waterloo Wrote:  Have you inspected the crankcase filter for contamination?

870 doesn't use one.

Your "mechanic" sounds like a complete idiot. You shouldn't be losing coolant until the thermostat opens. If the cooler was the problem and he fixed it correctly it wouldn't be leaking at all and you shouldn't be losing any coolant.

[Rawze]

(07-13-2020 )miker61002 Wrote:  ...The mechanic noted soot in the overflow tank
...

First of all, if there is contaminant in the overflow tank, a simple coolant sample sent to a lab would reveal what the buildup is. -- A black or dark ring in the overflow tank most of the time is not soot,.. but oil residue (mixed with soot because the oil in the engine was black). - If this is the case, then the most common cause of this is the oil cooler above all else on an ISX. Oil (and therefore soot too) makes a dark ring in the top of the coolant tank. Posting some pics here on the forum of what was seen would help too. <- when the oil cooler starts to fail and leak, oil gets into the coolant,.. not the other way around. Coolant does not get into the oil because the oil pressure is always much greater than the coolant pressure when the engine is running.


(educate yourself so you can question your mechanic.. your lively-hood and engine relies on your education these days against bad or lazy mechanics)...

next: Where is your mechanics brains at? -- your posts so far imply that he may not be that bright on all things ISX, and here is why...

* First of all,. .. after the egr cooler was replaced, the so-called mechanic ... ehemmm,.. should have filled the coolant system while pulling a hard vacuum on it to absolutely ensure there was no air trapped in the system. This is standard procedure ON ALL WET-LINER ENGINES for a reason. This is what cummins also heavily recommends. This is also what I do when someone comes here and the coolant is drained and re-filled for any reason.

your statement of making the "thermostat opens up" scenario -- is a tell-tale sign that this was not done. - There should be no "burping of the system" to get hot,.. you risk warping a liner or destroying your engine doing this if not done VERY VERY CAREFULLY,.. and is bad enough if you did it yourself and did not know any better .. but a mechanic?-- a professional mechanic that your paying good money for ?--- ANY PROFESSIONAL SHOP -- TO PROTECT THEIR CUSTOMERS ENGINES AND TO PREVENT LIABILITY should absolutely be pulling a vacuum on the coolant system whenever it is drained for any reason... To prevent engine failures ... to protect their customers interest... TO PREVENT A LAW-SUIT of your $40,000 engine happens to be the one engine that failed as a result of sheer laziness or negligence!!


WHY?:

Most lazy-mechanics out there would argue that is not a big deal .. except -- THE ISX IS A WET-LINER ENGINE!!!--- and ALL wet-liner engines have a serious weakness against any air trapped in the coolant system. THIS IS ESPECIALLY A PROBLEM whenever an egr cooler is replaced, as the trapped air is almost always in the egr cooler and around the liners after replacing it. Even so, I have seen engine failures when someone replaces transmission coolers, radiators, especially egr coolers,.. etc... - It is simply standard practice to pull a vacuum and sheer ignorance (or laziness) NOT TO on any wet-liner engine.

I see between 1 and 4 engine failures every single year for NOT PULLING A VACUUM on an ISX after draining and re-filling the coolant system,.. so not only is that repair shop using bad practices in just pouring coolant back into your truck and just asking for a law-suit from some one who's engine they destroy... but have gambled this with YOUR ENGINE TOO!-- <- Hence the other person on the forum here implying that your mechanic is an idiot and you should fire them.

-- I.E.> NOT pulling a hard vacuum on the coolant system when refilling it to remove the air pockets -- IS A SERIOUSLY RISKY MOVE!,.. so therefore you should never have to 'Wait till the thermostat open up' kind of any bulls#it,..unless you want to gamble with your engines destruction too. --it is that serious of a matter, and I would have been demanding they pull a vacuum on the coolant system to burp it before it was ever cranked up if I had taken my truck to those clowns as soon as they said that it needed driving and topping off again!.

-- NEXT-- you say you were loosing coolant at a high rate... -- the shop replaced the EGR cooler,,.;..that is great, maybe that was the problem,.. but AFTER THEY FILLED THE COOLANT SYSTEM ..AND PULLED A VACUUM ON IT TO BURP IT.. --- DID they continue on and pressurize the coolant system to 20-PSI and let it sit for an couple hours or so to ensure there were NO M ORE LEAKS>??

(oil or soot in coolant)...
--- STOP GUESSING --->---

TAKE AN OIL SAMPLE and send it to a lab to see if you are getting coolant seeping into the oil if you suspect liners, or head gasket, .. etc.. and for good measure at the very least if you have ANY suspicion that coolant could be getting into the oil.. AND AS WELL--- WHENEVER AN EGR COOLER FAILS-- the oil needs replacing right away as well. This is standard procedure and it is also mentioned on Quickserv for the ISX as part of an EGR cooler replacement procedures. -- BECAUSE --- unless there is a block-plate on the intake manifold for the egr piping (deleted engine) ... The engine ends up with just enough coolant getting into the oil as it goes thru the egr cooler, into the intake, and thru the cylinders, via past the rings.... to contaminate it, and the more you run it like that,.. the worse it gets. <- Cummins says this ... and it is bad practice for any shop NOT to change , or tell to have chenged the oil right away afgter an egr cooler failure and replacement.

An oil sample should be used to reveal any serious detection of coolant intrusion into the oil... anybody at all bother to do this?-- I doubt your mechanic did, .. and you as a driver likely did no know this... - Again,.. either ignorant mechaninc?,.. or lazy mechanic? -- take you pick.

again,... your mechanic should have informed you what your options were, and not just made stupid comments based on a bunch of guesses and assumptions.!-<- again,.. lazy or ignorant,.. take you pick! -- which one was it?


-- Educate yourself... That is the key to solving your problems,.. because no mechanic is likely going to the right things for you!. - it is your business your screwing over and no one else's if you do not do things right or rely on lazy mechanics that cannot even be bothered to pull a proper vacuum on the coolant system when they do major work to a wet-liner engine.


At this point...

- Get yourself a radiator pressure test kit... get the coolant system pressurized to no less than 20-PSI (5 psi over its operating pressure)... Let it sit for a few hours, or over night... FIX ANY LEAKS FOUND!.

-- i would say to send a coolant sample to a lab, but likely, they replaced the coolant, and it may be pointless on new coolant, as it may not have been run enough for a lab to see what the contaminant is yet.


--=====--

ALSO: you have a CM870... you established that ... how many miles? some back history,.. etc.etc.etc..