ISX oil leak

[TallBoy441]

I have a 06 isx cm870 that has started leaking oil all of a sudden. It appears to be coming from somewhere from around where the fan hub mounts to the motor. I’ve cleaned the motor up several times & haven’t been able to pinpoint where it’s coming from, due to everything being in the way. Right now it’s leaking about gallon a week & seems to leak a little more when pulling heavier loads. Truck has just over 1 mil miles. Anyone got any ideas of the possible cause ? I need to get this taken care of, as it’s making a mess all under my truck with the fan blowing it everywhere.

[RyanC]

Clean it up really good, and if possible disconnect the fan so it doesnt turn on. The run the engine at high idle and lay underneath and watch. If you cant turn off the fan just do the same thing but I would wear a face shield.

[Rawze]

Not saying this is your problem, but it is common ...

at a million+ miles, i would put my faith heavily into it being the cam bearings worn out, and the cam seals leaking behind the gear cover. -- just the first thing that comes to mind any ways, old heads that get worn out tend to leak behind the gear cover at the injector cam or valve cam as the bearings start showing copper.

Look for oil running down at the back of the gear cover where it meets the block just above the air-compressor. -- if it is wet there, then its a high possibility.

what usually comes next, if ignored long enough is a spun bearing in the head, Usually the one near the gear pump, where the engine brake harness connector is. If this happens, then you will loose the cam as well, sometimes rocker(s) too, and is a preventable couple thousand$$$ expense otherwise.

[Waterloo]

Go up to Autozone, or get on Amazon, and order the oil dye to trace the leak. You will need a few bottles, and the black light kit to see where the leak is coming from. It works.

[Chamberpains]

RyanC has it right. Gotta clean it and run it with the fan off. This can be as dumb as the oil fill tube got loose and is leaking or the blow by tube spitting a bit and the fan is blowing everywhere. I've also seen things on the back side of the front gear case leaking and the fan pulls the oil to the front side. Cam crank sensors leaking, valve cover leaks, air compressor mounting leak, cracked gear case, water pump gasket leak... There's a lot up there.

[TallBoy441]

   I cleaned the motor up good and the majority of the oil appears to be coming from around the crank seal area, there’s also some minor seepage from around the injector & valve cam seals. I ran the overhead today to get a look inside, as this is the first time it’s been open in about 260k. Every looked pretty good to my eye, but I’m not professional. I’m gonna try to upload some pics and see what you guys think or may see something concerning that I missed.

[Rawze]

need to do a couple three oil changes at about 3,000 mile intervals and get some of that soot buildup out of it.

[TallBoy441]

(08-11-2019 )Rawze Wrote:  need to do a couple three oil changes at about 3,000 mile intervals and get some of that soot buildup out of it.

Yes, that’s for sure. I’m going to tear it down in the next week or two and reseal everything in the front. Got to get crank pin & wedges ordered. I found a kit with all the blocking plates to stop the soot. Anything else that has to be done after there installed ? Also, do I need to pull the cams & inspect the bushings while the gears are off ? If so, how much more work will be involved, any special tools ?

[Rawze]

if you install any plates, you will need Unilevers or mommaburt to make a custom program. Otherwise, it will have a turbo derate all the time.

Also, a lot of those "kits" are not so good quality. I have seen many that come apart, crack, burn through, etc. after a few months or a couple years and take the turbo or engine out along with them.