Engine Repair (A1)Question 15 of 120
Coolant is leaking internally and the engine oil appears milky. The MOST likely cause is:
a.A worn timing belt
b.A clogged air filter
c.A failed head gasket or cracked block/head
d.A stuck thermostat
Explanation
A milky, tan appearance in the oil indicates coolant contamination, commonly from a head gasket failure or a crack that connects a coolant passage to the oil. Continued operation damages bearings. Pressure and combustion-gas testing help pinpoint the leak path.
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