Rear main seal would be leaking at the bellhousing, not in the turbo area. Clean the spillage with brake cleaner and monitor to pinpoint where it is coming from. I’ve just had my leaking turbo rebuilt as it was leaking badly, the cause was the thrust collar bearing on the cold side was worn. Worth checking your oil return pipe is not leaking, the gasket can break up causing a leak in that area

 

Okay thanks Parsnip,
I thought that area was also around the bell housing (pic 4, I am LHD) but I have also noticed a slightly louder whirring noise from the turbo so maybe I will be in a similar situation as you. I would rather it be anything but the rear main but I'll clean it off and take a good look. Any tips for getting a visual on the turbo oil inlet/outlet on the AWD models?

 

Clean it up and throw some dye in it. Make it easy on yourself.

 

Also on my drive this afternoon I noticed the whine was louder and I seem to have a reduction in acceleration. This makes me think it is most likely the turbo failing. Is the best way to check just taking off the plastic pipe that feeds into the compressor side and then checking for play on the prop?

Thanks again

 

Yes can pull intake or downpipe to check for play.

 

The leak itself is likely the turbo oil return line. The gasket is cheap and so is the seal for the bottom of the line, but replacing it requires dropping the angle gear.

If you DIY pay very close attention to the bottom seal when replacing, it’s notorious for folding over or not searing properly resulting in further leakage. Buy multiple seals, you’ll probably knick or break at least one when trying to get it seated properly.

 

Yeah I was looking into that return line seal and looks like a real PITA on the AWD. Do you think a leaking oil return would cause the turbo "whirring" noise I am hearing and loss of acceleration? Guess I'll make sure there is no play in the shaft before I try to do that replacement.

 

I don’t think the two are related unfortunately.

 

Yeah I am planning on getting deep into the inspection this weekend. Now that I think about it some more I realized that I am likely looking at a bad compressor side bearing/seal which is leaking oil out (pic 1 ) and I am not seeing blue smoke becuase the oil is leaking out the weep hole and diffusing in the air along the intercooler before being burnt off? Does that seem reasonable? I have never worked on turbos so I am still getting my head around it.

 

Its all speculation, reasonable, but still a guess until you dig deeper.
jack the car up on jackstands and get under , check the bottom of the turbo.
My turbo drain pipe coated the bottom of the car.
I diagnosed my turbo by putting my hand on it and starting it up from cold, I could clearly feel vibration.

 

I got into the inspection today and here is what I found:

Oil in the charge pipe and oil residue throughout intake piping:

(Pic of charge pipe with oil at lip of compressor outlet)

I put my hand into the compressor housing and tried pulling/twisting the prop. I could not feel any play (axial or radial) and the prop rotated easily without any noise/crunching when spun by hand.

The oil inlet and outlet on side of turbo/block. were dry so those are not contributing to the leak but you could see oil drips coming down on both the air in/out pipes on turbo compressor (though I am still not sure that those are the only source of oil)

I was fully expecting to find a damaged turbo after seeing all the oil in the air piping so now I am even more confused. Could the turbo oil seal be bad and still have no distinguishable play/slop?

(pic into compressor)

maybe this is more evidence for a bad PVC system as maybe it’s pushing too much oil into the inlet (but as I said before I don’t fail the glove test or dipstick smoke at idle)


I’m at a loss so any input is greatly appreciated!

 

its not rare to find oil in the air pipes.
The oil on the exterior of the turbo is often caused by a worn out rubber coupler pipe , the short rubber coupler
connects the air pipe to the top of the turbo, they become soft and leaks oil onto the turbo.

 

It’s pcv oil.
Replace the system and update the banjo bolt on the intake manifold to 31325709

 

UPDATE: Okay so I was wrong about the original turbo being okay. I took it off the car and found a ton of axial shaft play so it went in the bin. I picked up the exact same turbo with no play off a XC70 from a local volvo legend in my area for $140. I replaced the PCV and replaced the turbo and am back on the road as of yesterday with noticably more power.

In case anyone wants my two cents on the procedure for my AWD 2.5T V70 here are my main takeaways:

PCV
1. Get a crowsfoot wrench for the lower left intake manifold bolt. I fiddled with the wobble extensions for a long time before I realized it wasn't going to work. Not sure if there are slight differences between models but my thermostat housing was more in the way than the other pics/vids I saw.
2. It helps a lot if you have someone to hold the intake up while you thread in the banjo bolt, and as ScottishBrick says above make sure you update it to the recent model 31325709
3. When you get the oiltrap off the side of the engine the lower port will be plugged up with gunk. I saw a lot of people try to use compressed air but I found you want to do the opposite and use a shopvac. I blasted it with seafoam for a couple of days and picked away at the port entrance. I used a long ziptie and continuously fed it through while also using the seafoam and shopvac occasionaly. I kept doing this and eventually heard the shopvac clear the main bloackage and I could push the ziptie all the way though. Doing it this way also means less gunk pushed into your pan.
4. When you go to replace your injector seals I found it was easier to cut the o-ring insead of feeding it over those brittle plastic pintle caps. If you try to force it over one of those caps they will probably break becuase they are not meant to be loaded in that direction. Just cut the o-ring (careful not to contact sealing surface) pull it off and then feed the new o-rings over the pintle cap.

Turbo
1. There are a lot of varrying opinions about doing the turbo swap with the Angle gear on. I left my angle gear on and found it was fine. The only real pain point of leaving it on is getting the turbo drain pipe on. I practiced putting the pipe in with no gasket a few times and when I felt comfortable I put the gasket in warm water to soften it up, coated it in oil and forced the pipe in place. With the angle gear in it is more difficult of course but you do have space to get your arms up on both sides so it is not terrible. The main issue was getting the two torx bolts alligned back in place but with something forcing on the flange and antoher hand trying to start the thread you should figure it out.
2. Make sure you purge air out of the oil feed line by cranking the engine with the fuel pump and injectors disengaged. I left my banjo bolt loose and made a mess but I wanted to make sure the oil feed line was getting oil becuase when I took off my old turbo it looked dryer than I was expecting (maybe becuase the PCV pressure??).
3. Check your old downpipe gasket and match for the new gasket, I bought the wrong one initially (there is a circular ring version and then a metal flange version)

 

UPDATE: Okay so I was wrong about the original turbo being okay. I took it off the car and found a ton of axial shaft play so it went in the bin. I picked up the exact same turbo with no play off a XC70 from a local volvo legend in my area for $140. I replaced the PCV and replaced the turbo and am back on the road as of yesterday with noticably more power.

In case anyone wants my two cents on the procedure for my AWD 2.5T V70 here are my main takeaways:

PCV
1. Get a crowsfoot wrench for the lower left intake manifold bolt. I fiddled with the wobble extensions for a long time before I realized it wasn't going to work. Not sure if there are slight differences between models but my thermostat housing was more in the way than the other pics/vids I saw.
2. It helps a lot if you have someone to hold the intake up while you thread in the banjo bolt, and as ScottishBrick says above make sure you update it to the recent model 31325709
3. When you get the oiltrap off the side of the engine the lower port will be plugged up with gunk. I saw a lot of people try to use compressed air but I found you want to do the opposite and use a shopvac. I blasted it with seafoam for a couple of days and picked away at the port entrance. I used a long ziptie and continuously fed it through while also using the seafoam and shopvac occasionaly. I kept doing this and eventually heard the shopvac clear the main bloackage and I could push the ziptie all the way though. Doing it this way also means less gunk pushed into your pan.
4. When you go to replace your injector seals I found it was easier to cut the o-ring insead of feeding it over those brittle plastic pintle caps. If you try to force it over one of those caps they will probably break becuase they are not meant to be loaded in that direction. Just cut the o-ring (careful not to contact sealing surface) pull it off and then feed the new o-rings over the pintle cap.

Turbo
1. There are a lot of varrying opinions about doing the turbo swap with the Angle gear on. I left my angle gear on and found it was fine. The only real pain point of leaving it on is getting the turbo drain pipe on. I practiced putting the pipe in with no gasket a few times and when I felt comfortable I put the gasket in warm water to soften it up, coated it in oil and forced the pipe in place. With the angle gear in it is more difficult of course but you do have space to get your arms up on both sides so it is not terrible. The main issue was getting the two torx bolts alligned back in place but with something forcing on the flange and antoher hand trying to start the thread you should figure it out.
2. Make sure you purge air out of the oil feed line by cranking the engine with the fuel pump and injectors disengaged. I left my banjo bolt loose and made a mess but I wanted to make sure the oil feed line was getting oil becuase when I took off my old turbo it looked dryer than I was expecting (maybe becuase the PCV pressure??).
3. Check your old downpipe gasket and match for the new gasket, I bought the wrong one initially (there is a circular ring version and then a metal flange version)

the 2 bolts holding the oil drain pipe from the turbo are the bane of that job.
I would probably pull the angle gear if I did it again.

 

Even with fresh and fully functioning PCV there will be oil traveling through air intake, because of bore taper and worn piston rings in old engine.

 

Even with fresh and fully functioning PCV there will be oil traveling through air intake, because of bore tape and worn piston rings in old engine.

Yup for sure but I wouldn't use that as an excuse not to do a PCV though. My lower port was completely blocked up. If you see lots of oil in the intake and you are not sure when the PCV was done just do it anyway. I was passing the glove test and dipstick test so those are not always a 100% accurate indicator of when the system has gone bad I guess.