2010 2.0 Diesel oil leak by steering motor

[jkhackney]

Hi,

My wife has a 2010 2.0L diesel TDI (Legacy V) with 189,000km which has always been dealer-serviced. Last service 187,000km in May.

I took it to inspections for her last week and an oil leak was found under the engine, which is coating the steering motor/gear and tie rods.

The cylinder heads are clean, as is the area around the bellhousing and transmission. The leak seems to start at the oil pan gasket . In May, the dealer made no mention of an engine oil leak, so I suppose that the leak started since they did the work.

The engine oil level on the dipstick is 2cm above the "max" reading !! Could this be enough to cause the leak? And would the leak stop again if I drained the oil and replaced the correct amount? Would I need to re-set the computer (for the diesel particle filter) if I did this?

There are no indications of a blown head gasket that would leak coolant into the oil. The oil is not brown/green but the normal black color. No coolant is missing. Would a warning light indicate a head gasket issue?

I assume, now, that it's simply overfilled. Does anyone else have a hypothesis I should test (and how to test it)?

Thanks

Jeremy (in Switzerland)

[idosubaru]

pictures of the source of the leak are best.  Can you post pics?   Second hand info and descriptions of the oil leak path, rather than detailed focus on the source of the leak is often confusing.

Need to verify the source. Look for the highest and most central indications of the leak.  Where the oil falls down below isn’t nearly as helpful. 

The “overfill” is not the cause of the leak.  People have freaked out about high oil level for decades and it never causes leaks. It’s even common to purposefully overfill without issues.  If it was egregiously overfilled, maybe, but that doesn’t sound like the case here. 
 

online Subaru dealers have exploded view diagrams you cam compare to what you’re looking at as well to help identify leak sources.  Or you can screen shot a diagram and circle where you think the leak is - but a picture is way better since oil leaks can Combe confusing if you haven’t diagnosed and repaired them before. 

Edited November 30, 2019 by idosubaru

[jkhackney]

Woops, before reading your helpful response, I cleaned, drained, and re-filled it without taking photos.

The transmission oil is new and clean, and the oil on the engine was black. So I'm sure it's leaking engine oil.

The highest point of the stains was the oil pan / sump gasket.

The engine oil smells like diesel and it's conceivable that short trips have diluted it. I re-filled it with the oil I drained, and 750mL was left in my bucket when it was at the "high" mark on the dipstick. I tried placing a drop on a piece of paper to observe the oil and diesel separating, but I can't see definitive signs. That method probably needs experience to be useful. Or, it may just be a trace of diesel in the oil?

After a 30 second idle there aren't any drips. I'll drive it for a day or two, keep an eye out for oil on the bottom of the engine and on the oil level at the dipstick, and if anything interesting happens I'll post it here.

I'll find one of those online diagrams to understand what I'm looking at.

Thanks

Jeremy

 

 

 

[montana tom]

I'm jealous Jeremy;

They won't let us have diesel Subaru's in the US !     What kind of mileage do you get ? 

[jkhackney]

Hi Tom,

Sad, I do know that. What's the issue in the U.S.?

I put on a Thule rack which howls in the wind. Since we got it in 2015 I think(?) we've done 19k km (12k mi) and average 5.0L/100km or 48mpg U.S.  This is city/flat Autobahn and pretty hefty mountains, in all weather with up to 4 people inside. Just cruising on the flat Autobahn at 50mph it can average nearer to 50mpg, as if it were a much smaller car. I've never had a diesel or a turbo before, so the acceleration above 2000rpm is incredible for me. Six gears is cool.

Today it passed its re-inspection after I cleaned off the oil and let it sit all weekend to see if another drip started. I think there might have been one trying to come out of the electrical sensor-looking device on the left side of the block, just above the steering motor/gearbox and oil pan. It's a round black plate 2" diameter held on with 2 cap screws (5mm allen key) and it has a white wire coming out of it. I tweaked each cap screw a hair tighter, wiped the wannabe drip off, and it was totally dry two days later. The drip could have been brake cleaner mixed with oil from my earlier cleaning though ...

My problem may be a very small leak that accumulated oil for a long time, making it look dramatic.

I had tried to remove the turbo intercooler to inspect it better, but couldn't get the hoses off (didn't want to break the plastic one!!!). Is it just a matter of persistence to get the hoses to pop off? I was thinking of a worst case since the oil volume was so high: turbo leak --> diluted oil --> leaking oil

I'll update this thread if it/when starts leaking again.

Jeremy