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2012 MP8 oil in the coolant

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Hello everyone 

As the title says I have oil in my coolant reservoir. Back in July I had the cylinder head replaced by my local Mack dealer. Also the number 2 piston and cylinder was also replaced. Reason was a broken valve. 

Within hours of getting the truck back on the road I had oil in the coolant reservoir. I went back to Mack and they said that it might be just some residual oil left following the job and that I should just keep an eye on it. Two weeks later a bunch of fuel in the coolant reservoir as well so I ended up doing the cups on e new reman head. When they did the cups they also did a flush and installed new coolant reservoir.

Couple days later the coolant started to get black and back to square one. I ran the truck for a while and then did a flush myself again and new coolant reservoir.

Needless to say the coolant is black again and I have the same problem. Oil is clean and the coolant level doesn’t increase.

Truck has now 1502 000 km. Hours around 15000. Original engine just on the third head and numerous sets of injectors and cups.

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Weve had this issue before  we ended up having to do ALL the orings in the system , OIL COOLER/ THERMOSTAT ect the fuel in the coolant ruined all the coolant orings!

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