QuickNick

So I assume the blue smoke I can see when engine is hot is from worn turbo seals but how else can I check? I assume there would be oily residue in the in inlet side of the intercooler or something?

Glowplug

iTrader: (8)

Go for a run, then let the car tick over for 5 mins, then give it a rev, if it chucks out blue smoke then this would indeed indicate the turbo seals have/are going. It's not conclusive though just a good indication

Splitpin

May be from worn turbo seals, may be from worn piston rings (or damaged pistons), or possibly failing valve stem seals. Lots of oil in the inlet side of the intercooler is more likely to be from piston-related problems than the turbo.

One easy test is to take the oil cap off, hold your hand over it and check for pressurisation when you blip the throttle. Compression test worthwhile too. Would be easier to comment if we knew the age and mileage of the engine/turbo.

QuickNick

Its on my Starlet turbo.

I have just rebuilt the engine with new big end bearings, inspected everything top to bottom.

I recently bought a hybrid turbo 2nd hand, so the smoke must be coming from that, unless it is simply burning off oil in the exhaust system from blowing a head gasket before the rebuild.

I am fairly convinced I need a new turbo or a rebuild with new oil seals, if there are any recommendations of where to go I would be grateful (or if you have any other suggestions of what it could be)..!