My 2007 OUtback wagon 2.5 l smokes as soon as the engine gets warm.

I have located the source: motor oil is between the Right exhaust manifold and its surrounding heat shield. I have watched from below: once the manifold is hot, fumes of vaporized oil rise from between the manifold pipe and the heat shield around it. Awful smell & smoke. It's less of a problem after driving for a distance. I dont know what is leaking oil so that it can trickle down around the manifold pipe. New valve covers. No signs of bad head gasket, although I worry this could be the source. oil pan is a little moist towards rear, but I dont think that could spray oil over to the manifold. Any ideas? Would hate to replace head gaskets only to find another source. Jim

First thing to do is wash the engine top and bottomm. Next lest change the PCV valves.

 

What brand gasket did you use?

 

Did you change the spark plug bucket seals?

HG oil leaks. Very common. Virtually every one I look at has some amount of seepage.

 

GD

Hg leak yes possibly, but not one to jump to major conclusions here without a few more answers.

So if it is the HG and there are no other signs of a problem (no oil in coolant, no coolant in oil) does this guy have to go and change the HG anyway to be on the safe side or just keep driving it?

 

Is this a time bomb? could the HG fail suddenly and result in anoveheated engine?

No - the external leakage just keeps getting worse.

 

GD

The source of the smoke, is it at the front of the engine, or the rear?

 

So if it is the HG and there are no other signs of a problem (no oil in coolant, no coolant in oil) does this guy have to go and change the HG anyway to be on the safe side or just keep driving it?

 

Is this a time bomb? could the HG fail suddenly and result in anoveheated engine?

 

Not on these. The 05+ engines don't usually leak coolant, just oil. Subaru HGs almost never mix coolant and oil. Not unless you overheated the hell out of it already.