ISX450 coolant issues

[Rawze]

(04-21-2020 )Chubbs68 Wrote:  Evening everyone I have 13 386 that I have always smell coolant but never find at one point the coolant went brownish black then last year head gasket went out decided to do a in frame 600 hp upgrade. Still could smell it would lose about a gallon between services (10,000 miles). I mainly smell it on the passenger side under door and inside cab but no coolant inside cab so assuming heater core is good just did a service and coolant is getting dark again it doesn’t smell burnt my mechanic is baffled anyone got suggestions . Thanks all

sounds like your mechanic might be an idiot!. There are proper procedures for finding and solving this stuff. It is not rocket science ... stop guessing and wasting money!.

- A gallon every 10k miles ? -- That is a lot of coolant loss. - How fast you think I could find that coolant leak?.--- in my own driveway!!!

PRESSURIZE IT TO 20 PSI AND LET IT SIT OVER NIGHT!!! -- FIND THE DAMN LEAK(S) -- FIX THEM .. AND IF YOU SUSPECT COOLANT GETTING IN THE OIL PAN OR COMBUSTION GASSES INTO THE COOLANT .... PULL THE OIL PAN OFF IT WHILE YO DO THE TEST!

-- On another note ... One of the other common issues with black crap getting into coolant tank from an ISX is the oil cooler going bad. <- THIS IS ALSO WELL KNOWN!. -- Is it oil? -- Is it FUEL? -- or combustion gasses?. or is it something else. -- HAS ANYONE bothered to send the coolant off to a lab for analysis instead of blind guessing it like a fool? -- Anyone send the oil off?

-- Anyone check the transmission to see if the heat exchanger is going bad?-- Does the tranny have a coolant type heat exchanger?

-- Like i said .. not rocket science.

also --- WHAT ARE YOU CALLING 600hp upgrade?--- Something sounds fishy to me on this, as taking a mid-tier CM2350 engine and making it 600hp entails all new injectors, new cam, Turbocharger replaced with the one with the bigger exhaust impeller 400-series (or if I were doing it, would be a changeover to a 500-series VGT), and the new bottom-end piston-liner kit too. <- Very expensive to do correctly once you price up all new injectors (old ones most the time cannot be turned in as cores either, since they are different), overhead cam costs, replacement turbo costs, etc.l are all considered. -- I hope your mechanic was not a dumbarsse and only put just the bottom end/overhaul kit in it only then thinking he was doing something good to it. -- MOST of the mid-tier changes are int the top-end,.. not the bottom end (although both are required).

WAS the head replaced .. with a brand new EOM replacement head? -- Or a certified reman by cummins? -- or something else (aftermarket or was re-machined, etc)?.

Last but not least ... your mechanic not too smart for doing this unless he has some big ballz and deep pockets! --- all warranty from cummins is void when someone does not install the same tier components -- Were you even aware of this risk? -- Did he explain it to you up front that there would be ZERO FACTORY WARRANTY ON ALL COMPONENTS for defects, etc?? -- Totally Doubtful!. -- Hope he is the one going to be standing behind it for the next year if there are any defects on any of those components? <- Was this even considered? - I am thinking that it was not.

If they actually made that many mistakes... was that mis-informed of what it actually takes to change the engine tier and all its associated costs,.. and only changed the bottom end components like a fool + is unable to find coolant issues .... -- I FEEL SORRY FOR YOUR ENGINE AT THIS POINT! -- because you now will need a custom-made program to run it if that top end, cam, injector(s), turbo were not also upgraded at those high costs ++ and it point right back to what others are implying .. if he was that dumb ... almost assuredly .. your coolant issue could very well likely be a bad head gasket again... DUE TO INCOMPETENCE IN PROPERLY REBUILDING THE ENGINE PROPERLY!

Just pointing out what screams at me so far ... Hopefully I am wrong and your problems are not this severe,.. but I have my serious doubts on that engine being even half-way right if someone did half-an-upgrade to try to make it 600hp by only changing bottom end components ... and then likely followed up by not properly counter-boring it, etc.. + made all the other mistakes that are seen over and over on here every year by people and shops just like you describe.

-- these are the things that ran thru my head after reading your post, harsh as they may seem.