I have a 2004 saturn L300 v6 I just replaced the engine about 1 year ago. Brought a used engine from some junk yard way but East and had Jose auto repair here in stockton ca put it in. Went and got my car after he did that and had no problems till now. I just noticed that my water reserve looks like a light color brown maybe like a milk shake but it my water reserve not my oil . Checked the oil and it's fine. Plus my car is not overheating at all not even before I noticed this so I have been told oil cooler but i need to know for sure cause I don't have a whole lot of money so when I go to get the part I need to know what to ask for.

 

The oil cooler is pretty deep under the intake manifold. It will be a major labor charge to replace the engine oil cooler. Consider carefully the value of the car and condition before repairing a used engine. Did they replace the water pump and timing components when they installed the used engine? Does the engine use any oil between changes? I would hate to see you spend a lot of money trying to save a problem child.

 

you know I don't know. Do you think it's the one on the back of the radiator?

 

The engine oil cooler is deep in the v- under the intake manifold.I have not had one leak yet, however I have only run two of the v6 engines. My experience is much deeper with the 2.2 L 4 cylinder engines in the L200s. I am currently running an Lw300 with the v6 but I am only at 120k miles so far. The thermostat is also buried under the intake on this engine. Please check labor quotes before proceeding with repairs, surprises are not welcome in my book.
Andy

 

Glycol will leave a buildup of stuff that looks like oil. Are you sure it's oil?

 

Sent some pictures