Oil in the Coolant, even after changing Oil Filter Housing Gaskets

[BMWF36]

i have a 2015 435I GC. My car only has 35K miles and i changed the OFH gaskets in November. Yes, you could tell that they were bad. Unfortunately, two weeks ago i received a message that my coolant was low, so i open the hood and noticed that one of the hoses that connects the OFH and the thermostat was busted. so i proceeded to replace the hose, but when i drained the coolant i noticed oil in the coolant again. so i decided to replace again the OFH gaskets thinking that i did something wrong last time. i drained and flushed again all the coolant, but after doing all the work i am still noticing oil in the coolant expansion tank.

any ideas where else the oil could be leaking into the coolant lines?

the car drives perfect no problem at all, no code, no engine light.

Thanks!

[mandd]

Unless you used a chemical cleaner you will never get all the oil residue out.

This involves draining all the coolant, flushing the heater core and refilling with water and a chemical cleaner then running at idle with the heater on high for about 10 minutes.

After this drain system flush heater core and fill with clean water and run again for about 10 minutes, this is to remove the cleaner.

Empty system and fill with the correct ratio of coolant and water.

Mark.

[BMWF36]

Thanks. I will try it again.

[Joseph.N]

Keep in mind, the oil filter housing is an Oil-Coolant heat exchanger module.