I've had an on going issue with my zed now for some time. The issue is that it burns oil, to start with it grey wafts of it at idle and plumes of grey/blue between 2 and 3k it was honestly like a smoke machine, terrible. After a compression test revealing an average of 160 psi across all cylinders and no oil being ingested pre throttle body it was decided it was most likely the rear turbo oil seals, inspection revealed that a pool of oil was building up in the rear compressor housing then being pushed out when the airflow was sufficient. So these were rebuilt using staggered gap rear seals etc, the Pcv system was all replaced at this time too, with non oem Pcv valves and new silicone hoses. This cured the issue almost, almost, but left me with some smoke on deleration, or after prolonged idle that initial rev, it will idle all day esp with the air con on without a single puff.
After some recent work on the oil filter tree I noticed oil coking from burnt oil on the CHRA of the drivers side tub, consistent with a cigarette like waft of smoke from that area now and again. I inspected the oil feed line as I was under the impression that oil from the core couldn't leak this way, certainly not without massive amounts of smoke. There was no evidence of the feed line leaking however and I was left thinking its obviously working its way out the rear seal again via that route, as well as through the exhaust.
A while passed and a few days back I had a look after a hot drive, sure enough oil was visible from the oil feed line, it obviously leaked under high pressure and burned off to the underside. Anyway I tightened this up and bobs your aunt that problem has now gone.
So back to reading about the fault and speaking to a friend we came to the conclusion that it may be the valve stem seals, these may be allowing the thinned out hot oil to be sucked into the combustion chamber and gasses to be leaked out into the heads. This would obviously create blue smoke and create resistance for the turbo's to drain into the sump properly. The car doesn't noticeably burn oil, I've done about 2.5k miles this summer and its no needed topping up since my spring oil and filter change(only use the car in the summer).
I have used the search function and google and found that seal replacement is possible with the engine in situee and head on, I just haven't got access or space to crane the block out right now and it came out when the turbos were done so service items were done very recently. Whilst some threads indicate that my issue sounds prime of valve stem seal failure, correct compression, low consumption, blue smoke on deceleration others say the seals rarely if ever fail on these cars and I would be wasting my time and money.
Could some one please discuss some sense with me and highlight anything I may have missed. It would be a terrible waste to pull a turbo or disassemble the top end for no good reason. I am looking to borrow a leak down tester of a friend to see what results that produces, id really like to have a summer without blue smoke trails, it doesn't happen all the time but you can guarantee it will happen when everyone is looking.
I've had an on going issue with my zed now for some time. The issue is that it burns oil, to start with it grey wafts of it at idle and plumes of grey/blue between 2 and 3k it was honestly like a smoke machine, terrible. After a compression test revealing an average of 160 psi across all cylinders and no oil being ingested pre throttle body it was decided it was most likely the rear turbo oil seals, inspection revealed that a pool of oil was building up in the rear compressor housing then being pushed out when the airflow was sufficient. So these were rebuilt using staggered gap rear seals etc, the Pcv system was all replaced at this time too, with non oem Pcv valves and new silicone hoses. This cured the issue almost, almost, but left me with some smoke on deleration, or after prolonged idle that initial rev, it will idle all day esp with the air con on without a single puff.
After some recent work on the oil filter tree I noticed oil coking from burnt oil on the CHRA of the drivers side tub, consistent with a cigarette like waft of smoke from that area now and again. I inspected the oil feed line as I was under the impression that oil from the core couldn't leak this way, certainly not without massive amounts of smoke. There was no evidence of the feed line leaking however and I was left thinking its obviously working its way out the rear seal again via that route, as well as through the exhaust.
A while passed and a few days back I had a look after a hot drive, sure enough oil was visible from the oil feed line, it obviously leaked under high pressure and burned off to the underside. Anyway I tightened this up and bobs your aunt that problem has now gone.
So back to reading about the fault and speaking to a friend we came to the conclusion that it may be the valve stem seals, these may be allowing the thinned out hot oil to be sucked into the combustion chamber and gasses to be leaked out into the heads. This would obviously create blue smoke and create resistance for the turbo's to drain into the sump properly. The car doesn't noticeably burn oil, I've done about 2.5k miles this summer and its no needed topping up since my spring oil and filter change(only use the car in the summer).
I have used the search function and google and found that seal replacement is possible with the engine in situee and head on, I just haven't got access or space to crane the block out right now and it came out when the turbos were done so service items were done very recently. Whilst some threads indicate that my issue sounds prime of valve stem seal failure, correct compression, low consumption, blue smoke on deceleration others say the seals rarely if ever fail on these cars and I would be wasting my time and money.
Could some one please discuss some sense with me and highlight anything I may have missed. It would be a terrible waste to pull a turbo or disassemble the top end for no good reason. I am looking to borrow a leak down tester of a friend to see what results that produces, id really like to have a summer without blue smoke trails, it doesn't happen all the time but you can guarantee it will happen when everyone is looking.