Updates.
In earlier updates i changed the lower part of the turbo return pipe due to oil leaking onto the manifold. Not enough for massive concern but enough to cause a whiff of oil when pulling up at traffic lights.
When lower part of oil return pipe was replaced, noted chemi metal all over the top part from a previous bodge. Replaced lower pipe and little difference and still weeping a bit as i reused the old gasket.
The problem with diagnosing this leak is visibility is terrible from top and bottom.
This is the view from the bottom when on a lift.
Access looks ok in pic but subframe is right in the way.
Exhaust and driveshaft, and gearbox too.
In reality its a right carry on to gain access to inspect and even harder to change parts.
Close up of return pipe join separating the two pipes with phone wedged in.
As seen wet with oil. I tried to borescope the return area, but was inconclusive to what was the source of the leak as again, access terrible.
To check turbo i took the pre cat lambda out and used the borescope to inspect the turbine wheel to see if it was weeping oil and any oily deposits, to see if the rear turbine seal was leaking.
Looked pretty dry so assumed OK.
Came to the conclusion that the leak was either the top part of the oil return pipe or the top return pipe gasket. The top hard pipe can crack and is right above the exhaust manifold so was a candidate.
As above access is terrible so quickest route was to take the cold side of the turbo off which is not too bad to do. Half hour and the turbo core is out.
With turbo removed i was still not 100% if it was the gasket, oil return pipe or core leaking as basically oil all over. The top part of the oil return pipe had tons of burnt oil on the outside and a dent in it for some unknown reason as somebody has been in the area before.
Turbo after clean up.
Took a gamble on it being the gasket leaking and dripping onto the manifold.
I had a spare top return pipe in good nick, so cleaned the joint faces up so they were perfectly clean and fitted new oem gaskets on both joins and torqued to suit. All back together in 2.5hours total.
Took it for test drive, giving it a few miles to burn the oily residue off. Was skeptical if fixed or not, but seems to be OK and no more oil fumes on idle. Done 50miles and checked the return pipe as can get hand down the back and all seems to be dry so will run it and monitor. If it comes back ill change the turbo core.
A few parts have been arriving so more work to do soon.
Thanks for reading!!