How do you know there's oil in the cooling system?
If the coolant is just brown it could mean that its old coolant, and you could start with the simplest and cost effective thing is a coolant flush.
If after that and you discover your coolant is still brown, then it means your oil cooler lines may have a leak and is going into your coolant, or a blown headgasket or possibly a cracked head/block. I would put my money on the headgasket though.
There are tubes that run from the block into the head that carry oil and coolant. This is to cool and lubricate the head and valvetrain. In order to keep the coolant and oil in their correct tubes, there is a gasket between the cylinder head and block. It has holes cut into it that match the cooland/oil passages and allows it to pass while sealing around it. If your engine has run hot (the usual cause for a blown headgasket) it warps the head an leaves a gap between the head/block. When this happens the pressures inside the cylinder escape through the weaker gasket material, and usually break the seal on the oil/coolant passages.
Goodluck.
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Sunday, February 21st, 2010 AT 2:47 AM
