ERG, Oil Cooler or Head Gasket? What do you think?

[johnobie]

EGR Cooler or Oil Cooler or Head Gasket ? What do you think ?
EGR Delete through ECU, catch can.
Cooling system/expansion tank flushed out twice, Brown/Orange Hoat scum no blackish scum.
Replaced radiator and all hoses pressure/vacuum test.
Over 10 week blackish SOOT build up in coolant tank no diesel smell, coolant loss 100 ml
Drive up Mt Tambourine engine temp 98 deg
DPF burn temp okay data log
Combustion gases test not positive ?

[Grippy]

Coolant temp of 98 is fine, mine, reaches that, then the fan kicks in and brings it back to 89 or so.
100ml of coolant is next to nothing. Bit of black sludge in these oil burners is normal.

[johnobie]

Thank you

[drover]

I don't know about the black stuff, I would be keeping an eye on it, the original
sludge was from the stuff Jeep put in to "condition" the coolant or some such rubbish, leak seal I always thought......... as to what I'm not sure, Soot first comes to mind, oil mixes and rarely is black unless in large doses ............. would have thought EGR system would be lower pressure than coolant, manifold vaccum, so coolant in EGR not soot in coolant ?????????. hose residue ??????

Monitor everything and see ........... take engine cover off so can view things easier and if possible get a fridge carton, open it up and lay it under the vehicle, quick visual on any snail trails.

[johnobie]

Thanks for the reply and help.

[johnobie]

Yes the blackish scum soot is internal combustion engine in coolant it seem to be a minor head gasket leak.
I used Nulon Permanent Head Gasket Repair with DuPont™ Kevlar® fibre & liquid resin provides the ultimate strong long lasting fix. Formulated to permanently seal it seem have done it job

[bjm]

My pick would be oil cooler leak .Obviously you would have done a cooling system leakdown test!