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Q: Engine pouring oil into radiator

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My Mazda blew a head gasket, so I had to install a new engine. When I started it up with the new engine in the truck it poured all of the oil out of the engine into the radiator! I tried putting in another new engine and it did the same thing! Help! Do you have any ideas on what’s happening and how to prevent this?

The only way this can logically happen is if an oil line from the engine is being connected to a failed "oil cooler" inside of the radiator. The engine oil is under far greater pressure than the coolant in the radiator, so the "leak" inside the radiator is one-way. Most often, this oil cooler is used by an automatic transmission not the engine. Double check any oil line from the engine being routed to the radiator end tanks. A certified professional from YourMechanic can come to your car’s location to inspect the oil leak to verify the problem and advise you on corrections.

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