Fuel dilution and water - Oil Analysis

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Nardulli

GOLD Star
Joined
Jul 12, 2025
Threads
8
Messages
111
Location
St Louis, MO
Hello All,
Well, there's trouble. My 100 performed flawlessly during my late October Death Valley run. Finally got the rig trucked back to St Louis. Brought it in to my shop and did an oil change. Yikes The oil was brown-ish. Took a sample, see results below.

I had installed an aftermarket radiator when we did the timing belt job. It has a very small leak. Too small to require the addition of coolant. I just received a new OEM rad, which we will install asap.

Here's my question: my experience leads me to think head gasket. Once I have a sealed up radiator, I can pressure test the system. The one area of the engine that I have not touched is the complex coolant bypass system. Other than head gaskets, are there any systems on this engine the failure of which can lead to coolant migrating to the oil?
 

Attachments

But there's no significant level of sodium or potassium? Typically these would be present if it was coolant contaminating the oil.

I wouldn't jump to blown HG. Could just be condensation? Check or just go ahead and replace your PCV valve and hoses.
 
Back
Top Bottom