what causes oil to leak into the radiator?

Answer 1

blown engine gasket?

oohhhh nooooooooo

$o $orry

Answer 2

Most often a leaking head gasket. Head gasket rarely "blow" as you hear "blown head gasket" unless you are running 8,000-13,000 RPM's like in drag racing and "Top Fuel" cars. The cylinder head will gradually warp (fraction of a millimeter) and the combustion pressures will push oil or exhaust gasses into the water jacket (coolant). If gasses are getting into the water jacket, you'll know very quickly as the pressures will cause an over flow of your radiator bottle.

The other two items that will cause oil to get into the coolant is that there are "oil coolers" inside of your radiator. The transmission cooler is typically on the passenger side of the radiator and, if your car has one, the motor oil cooler is on the driver side of your radiator. Rarely these internal "coolers" will rupture and either transmission fluid or motor oil will get mixed up with coolant. I know the Cadillac's have both internal "oil coolers" inside the radiators.

It does require some extra care to flush out an engine cooling system that has had oil inside of it. Hot water and some kind of soap (like dish soap) needs to be run through it or just fill it up with plain water and drive it around awhile and then drain it again and then fill it again and repeat until the water looks fairly clean when you drain it again.

Good Luck!

Answer 3

Could be a number of things, blown head gasket is one possibility, and the most likely, but then again, depending on make and model and if automatic transmission or not, if the transmission oil cooler is built into the radiator, there might be a leak in that area where tranny fluid is getting in the water.
A radiator shop could test to see if that is the problem.

Answer 4

If it s engine oil, possible causes are blown head gasket or crack between the coolant and oil passages in the cylinder head.
It s also possible to get transmission fluid into the coolant on most modern automatic transmission equipped cars. Most all modern cars utilize a transmission cooler located inside the radiator. If this cooler develops a leak it will fill the coolant (low pressure) with transmission oil (higher pressure) when the vehicle is driven.

Answer 5

Faulty water pump/broken head gasket/cracked head/cracked engine block...it's probably the water pump, but any of the parts I listed could cause this type of problem.

Answer 6

Let me guess. GM vehicle with a 3.1 or 3.4 engine. If so the intake gaskets.

Answer 7

cracked block or blown head gasget. How bAD DID U OVERHEAT IT....

Answer 8

Could be a headgasket problem.

Answer 9

blown head gasket....not good.