Oil Analysis - Head Gasket Problem?

[woodman60]

I've read many of the 4th Gen V6 head gasket threads, but wanted to start a new thread with my specifics. I've had my 2005 for a couple of months now and this is my first oil change.

I have no rough running symptoms or engine codes. No significant loss of coolant. No white smoke in the exhaust.

Despite that, my Blackstone analysis suggests coolant in the oil. Am I on borrowed time? What else should I do to diagnose this? Compression test?

Runs like a top with 192K, but the head gasket discussions have been freaking me out...now this. I'm on the verge of investing in significant suspension rehab/upgrade, but don't want to do that if a $3-4K repair bill is in my future.

 

[mannydantyla]

It looks like it, yes.

For what it's worth, my last vehicle was a Jeep XJ and I was having overheating issues I couldn't figure out. So I sent an oil analysis in to those guys. They showed that I had coolant in the oil because they found Potassium and Sodium in there (at smaller levels than yours but only a few hundred miles on the sample). No other tests showed positive for a head gasket leak though (compression was good, it passed the combustion-gases-in-coolant test, no signs of coolant in oil or oil in coolant other than the oil analysis)

I took the head off and the head gasket was not blown but it looked like maybe combustion gases were escaping past it. I took the head to a machine shop and it was warped. I fixed everything, put it back together with a new head gasket, and it was perfect and I drove it in the middle of July for 10 straight hours. Later that trip I was going too fast up a very steep mountain pass for a 21-year-old vehicle and it overheated pretty badly. After that I couldn't drive faster thant 65mph without it running hot and risk overheating. When I finally got home, I took the head off expecting the new head gasket to be blown but it was perfect and the head was not warped. I put it back together again with a new head gasket but it still runs too hot on the highway. So I said "screw it!" and bought a 4Runner

So, I'm not sure that story will help - maybe it will illustrate how very difficult it is to diagnose a small head gasket leak. I think an oil analysis is the "pickiest" test you can do. Maybe it's too picky though and can cause a false positive. But there is a sign that there is something wrong with your head gasket and that warrants further investigation. If compression is good (test with the engine hot), it passes the combustion-gases-in-coolant test, you're not loosing coolant and/or it's not turning brown or getting milky looking.. then I would change the oil, drive a little more and send in a new sample. No additives, no weird oil. See if they still think you have a HG leak.

The good news is the rest of your oil analysis looks great! Maybe there is no contamination or at least you caught it before it could hurt the engine. In my case, the metals found in the oil sample where alarmingly high even for a 250k+ engine.

 

[woodman60]

Sounds logical. I did not know what oil or additives might be in there since I didn't own it when they went in. I'm planning to run the exhaust gases in coolant test and compression and go from there.

 

[Keros]

A leakdown test may also prove a problem within the cylinder.

However, a leakdown could indicate a problem with the rings, valves, or headgasket. There'd be no way to know where the leak is.

It's a pretty obscure test:

https://en.wikipedia.org/wiki/Leak-down_tester

 

[mannydantyla]

However, a leakdown could indicate a problem with the rings, valves, or headgasket. There'd be no way to know where the leak is.

I don't think that's true, actually. I've never done a leakdown test myself, but I have always been under the impression that it was a far better test for finding the source of a compression leak than a compression test itself. If you hear air coming out of the tailpipe, it indicates a leaky exhaust valve. Air coming out of the throttle body or carburetor would point to a leaky intake valve. Air coming out of the breather vent or PCV valve fitting would tell you the rings and/or cylinders are worn.

If the air leaks into a neighboring cylinder, that cylinder will likely have a valve open where the air would escape, and that could be a false positive for a leaking valve.

But we're getting way ahead of ourselves here. OP needs perform the basic tests and go from there. Definitely don't jump to the conclusion that anything is wrong with his engine unless there is a well known defect or something, and I don't know these engines as well as others (just joined this community) but iirc there is no defect. Not like Suburu engines, for example.

 

[Elan750]

I also have an 05' and also got the same analysis. 150k. Its been a year now and ive only had to add about 6oz coolant in the year. I plan on pretending it never happened.:wink2:

 

[ZiaMan]

If you want a second opinion, I would send a sample to Terry Dyson, who is THE MAN with used oil analysis.