Q: My car inadvertently got coolant into the engine through a broken seal and . 1.5 gallons. What is the worst i can expect to happen

asked by on February 22, 2017

I have a 2012 C250 Mercedes. Somehow during a service process, a seal was broken along with the timing belt and my car lost about 1.5 gallons of coolant over 1 week. During that time, I drove at speeds over 55mph (interstate)... and yes, at one point, the car temp hit 120... I immediately parked my car and returned it the following day to the dealership. The oil was noted as being milky and was changed 4 times according to the mechanic. Supposedly the car was repaired again, but I have friends that are stating my car possibly has metal fatigue and the engine might have problems down the road. One friend suggested looking at the oil pan, but other than checking for shavings, what would that tell me. The car has not been driven since the repair job... too scared to drive it. So is the engine going to potentially fail? What would the oil pan tell me beyond the shavings?

My car has 71420 miles.
My car has an automatic transmission.

Hello, and thank you for writing in. With such dramatic failures and so many opinions, it is easy to become confused and worried. Checking the oil at this point will not tell you much. Any metal shavings that have come from the engine have been cleaned out with the 4+ oil changes that were done. Drive the car 30 miles and that will be a relevant test. Overheating is the one the worst things you can do to the engine as a whole, but it sounds as if you were able to gain control over the situation quickly. It’s repeatedly overheating, or overheating to a point where mechanical damage is done that you need to be careful with. 280 degrees Fahrenheit will destroy the engine. It is impossible to tell if the engine is going to fail tomorrow or in 10 years. What we do know is that you have fresh oil, fresh coolant, a new timing belt, and a new head gasket. This makes you better off then most vehicles driving down the street. If the vehicle is running fine, carry on per usual. If there is any cause for concern or troubling symptoms, contact our service department for a second opinion and all over safety inspection.

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