Bad Head Gasket?

[onewhippedpuppy]

I'd like confirmation from the braintrust here, haven't had to deal with this before.

2007 Pathfinder V6, teenager car with 155k, owned it for 5k, clean one owner with no maintenance history. No overheating issues, but the coolant is a milkshake with a distinct oily feel to it. Coolant is slightly low in the expansion tank, and definitely bubbles with the radiator cap off, enough so that I can't run one of the testers that checks for exhaust gas because it just contaminates the tester. Oil looks good, slightly off of full on the dipstick but it's been almost 5k since we changed it. No outward signs of an issue, it still runs great.

So, any other options I should consider? I haven't pulled spark plugs and ran compression tests on each cylinder, that's my next step.

[yel911]

White smoke out the exhaust.

[onewhippedpuppy]

Originally Posted by yel911

White smoke out the exhaust.

Nope, none obvious.

[sc_rufctr]

It may not be the head gasket.
Does the engine have an oil cooler, cooled by the coolant system? ()

The oil coolers can fail leading to oil in the coolant system.

cool coolant cooled... cool coolant cooled... cool coolant cooled... cool coolant cooled...
cool coolant cooled... cool coolant cooled... cool coolant cooled... cool coolant cooled...
cool coolant cooled... cool coolant cooled... cool coolant cooled... cool coolant cooled...

[drew1]

Automatic Trans, if cooler is in radiator could be it.

[wswartzwel]

Nissan had an issue with trans coolers... they would also get coolant into the transmission and cause transmissions to fail.

[fastfredracing]

I have done a handful of head gaskets on that motor . They all showed coolant loss, overheating, and white smoke out the exhaust . My tester also lit up , showing carbon in the coolant .
Im with everybody else, Id be looking at coolers first . I cannot honestly remember if that has an external oil cooler or not . I think it does for some reason. Oil filter mounted like Honda uses ?

[sc_rufctr]

Part number 1.... If it is that an easy & inexpensive fix.

[fastfredracing]

Originally Posted by sc_rufctr

Part number 1.... If it is that an easy & inexpensive fix.

That is what I had pictured in my mind . I would start there. Hard part is getting the cooling system clean again . Every hose will be softened and eventually fail

[onewhippedpuppy]

Thanks guys, seems like that might be a culprit. I assume 1 and 7 are the coolant connection?

I was also a little perplexed because it doesn’t seem to match the typical head gasket failure mode. My only pause is the fact that there are bubbles in the coolant system, but I suppose that could be air introduced by the leak to the oil system?

[fastfredracing]

And, while I am sitting thinking. before you shotgun any parts at it, Investigate those bubbles in the rad.
I would drain it down maybe 3-4 inches, so that you can then use your head gasket tester without picking up Nestle's quick milkshake in it. I am assuming you are using one of those testers that draw up the gasses through blue dye used where the cap goes ?

[onewhippedpuppy]

Fred that’s exactly it. I was thinking of just using it in the overflow, any reason that won’t work?

[Dansvan]

Get it to operating temp, with radiator cap off, put a balloon or latex glove sealed around cap opening. IF it inflates and blows off rather quickly, well, there you go.

[onewhippedpuppy]

Tonight I got it up to operating temp and tested at the overflow, which appears to be pressurized btw, and no sign of hydrocarbons. To be safe I’ll probably drain a good amount more coolant out tomorrow night and try to repeat the test right at the radiator. The oil cooler is about $400 so I don’t want to throw good money after bad. Again I’m having a hard time thinking head gasket, it warmed to a steady temp just under 1/2 on the gauge and didn’t move, didn’t smoke, didn’t stumble, etc.

[john70t]

(aw geez guys, at least the water pump is lubricated)

[sc_rufctr]

"The oil cooler is about $400 so..."