Hi guys!

I took a photo from my baby LR3 coolant overflow tank.




What is it?

The oil dipstick looks good.

 

Why is it empty?
Are you experiencing physical symptoms?
What about the back of the oil fill cap?

 

Looks like oil in your coolant reservoir. Not good.

 

I agree, that looks like oil.

 

Why is it empty?

on the photo is a part of coolant overflow tank. My coolant level is steady. I don't lose any coolant.

Are you experiencing physical symptoms?

no physical symptoms

What about the back of the oil fill cap?[/QUOTE]

back of oil fill cap is clean and dipstick is clean, the oil is clean



I changed the radiator a year ago and it's under warranty.

I think it's either the engine oil or the transition oil in my coolant.

I've owned this car for 10 years and it has 180K miles. Never changed transmission fluid and filter.

Please help me diagnose. Thank you for all ideas.

 

Oil in the coolant "could" be from a leaking head gasket, or a cracked block. Either way, it is not a good sign. Watch for coolant to get low, or oil to get low, and maybe do a check for exhaust gas in the cooling system. Or someone dumped an additive (or oil) in the coolant. A coolant flush may be a good idea to start with.

 

Wait... so there is coolant in there? I thought it was empty also. You are not used straight water, are you?

 

How to tell the difference between engine oil and transmission fluid in the coolant?

 

yes, there is coolant there, but I added a little bit of water on top just to see the level.

For some reason, I don't remember why, when I was flushing the radiator my coolant and water (50/50 mix) didn't mix well and I have water in the overflow tank.

 

Resolution:

1) it was cracked oil cooler ( $50) and super easy change
2) cleaning the brown sludge is a pain and takes time. I used Simple Green PRO with instructions on their website https://simplegreen.com/cleaning-tip...tive/radiator/