Turbo seals

[dave friday]

Afternoon all,how do i find out if the seals are shot?has anyone replaced them,how easy was it and did it work?.
Ta.

[ewenmaclean]

Hello,

generally if the seals are gone you're likely to have a lot of play in the shaft - it's hard to know without actually taking it apart. If the exhaust is oily that indicates likely turbine seal failure, and if there is oil pooling in the compressor or later then it indicates possible compressor seal failure - you will get some oil there from crankcase ventilation though. Rebuilding turbos is not a great idea yourself in my opinion as the central bearing assembly has to be balanced - some people say they can do it but I wouldn't myself as you risk serious damage to the engine if it becomes unbalanced.

What are the symptoms you have that make you think the turbo seals have gone?

Ewen

[dave friday]

Hi Ewen and thanks for your advice,its using a lot of oil 1/2ltr in 150miles,the exhaust tail pipe is sooty but not oily,the inlet is a bit oily.
The engine had a complete rebuild 40,000miles ago [rebore, new head, bearings,oil pump etc].

[ewenmaclean]

Hello,

just to go back to basics - have you checked that you have the right amount of oil in? That may seem stupid to ask, but if you overfill it then the turbo seals with leak a bit. It could be leaking into the compressor side and burning the oil - is there any blue smoke when driving? I would consider checking the CCV for effectiveness - they have a regulatory valve inside which control the crankcase pressure - if they get stuck and clogged up then this pressure has to be released somehow and can be through just about anywhere usually resulting in visible oil leaks, but equally possibly through the turbo oil seals. Equally if it is stuck open it can allow too much oil mist to pass into the compressor.

I am assuming that your rebuild was good and your rings are ok, but they might not be and the engine might be ingesting oil. If you install a "catch can" - where you put a vented can of some sort from the hose that comes from the ccv, and block off the ccv port to the intake, then you will get some idea of how much oil is being carried in the venting process, and whether the turbo seals have gone.

I have an external oil cooler, but my oil level sits and stays at around the minimum mark.

Ewen

[dave friday]

Thanks for that,i will check the ccv again [plus catch tank ect].i have an front mounted oil cooler and will try running the oil at the lower dipstick mark [as you do].
There is a possibility that the valve stem seals are leaking as the gasket and seal kit is of poor quality[the flywheel end oil seal is leaking!].
Regards,Barry[aka dave friday]