Q: 99 F250 V10 oil in coolant

asked by on February 22, 2017

99 F250 V10 had oil in coolant, it look thick and tan colored on top of the coolant. Trans fluid and oil look normal. First sign of the trouble was pressure built up and blew hose off heater core Sunday.

So we put the hose back on heater core and changed out the oil cooler. The old cooler showed clean coolant going in and oil mix coming out. We Flushed radiator one time with dawn, probably not enough because still had some oil in it, but drove two days no trouble, but it started to overheat this am and I shut it down. plan to flush radiator several times tonight.

Engine running strong all along.

Will the oil in the coolnt damage other parts like thermostat, water pump, heater core or radiator cap?

Any other suggestions?

Thank you.

My car has 250000 miles.
My car has an automatic transmission.

You will need to flush system out a few times and then make sure to flush out all the dawn you are using or the dawn will foam up. You should replace the radiator cap if you cannot clean out all the oil sludge from it. Other than that the oil should not harm any other cooling system component. You may have to replace the thermostat if it does not open up and close properly.

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