2.5 tdi exhaust oil leaking

[luke1135]

I put a 2259 turbo on and had it remapped to suit. Goes very nicely. Unfortunately soon after doing this I started getting a lot of engine oil leaking into the exhaust. Assuming the seals had gone in the turbo (it was a 2nd hand unit) I send it away to get rebuilt. 400 euros later it came back looking like new but as soon as I ran it up the oil was leaking again from the turbine side into the exhaust. So either:
A. They did a crap job of rebuilding the turbo (it comes with 24 month warranty fortunately)
B. Oil is getting into the exhaust before the turbo.

Starting with option A I blocked the oil return, blew into the turbo oil feed line and can hear air escaping. I reckon this means the seals are buggered but air is thinner then oil so maybe this isn't unusual.

As to option B - my first thought was piston rings or valve stem seals - but there is a lot of oil (1 drop a second) coming out and I'd imagine that the engine wouldn't run nicely or even run away if it was getting that much oil into a cylinder. Also I think the combustion would leak into the crankcase and make a lot of smoke come out the breather - and theres very little pressure coming out the breather.

Anyone got an opinion? Looks like I'll be pulling the turbo off either way. I guess once turbo is off I can check if oil spray is coming out the manifold

[zollaf]

is their oil on the intake side of the turbo or in the intercooler or any other pipework ?
if not, call the place who rebuilt the turbo. how much did you pay ?

[luke1135]

No oil in the compressor side or any of the intake hoses - just the exhaust. Yeah I think they ****** the rebuild up too but best I make sure of it before I give them a piece of my mind...

[zollaf]

yes, in that case it must be the turbo leaking. 400 euros should have got you a new housing with bearings and seals. i would speak to them and see what they say.

[adamss24]

Luke, that turbo was very low mileage, the seals should not have gone in it at all so soon ! I would check boost pipes as larger turbo's need revs/boost in order for the seals to stop leaking oil in the intake ! I would also check the breather under the turbo and replace to the later AKE breather as they never clog anymore. Don't remember anymore but is there a oil restrictor on the oil intake ? That would be one of the reasons the seals will fail...or too much boost request !

[luke1135]

Back to my first question should the seals be airtight? Because I can quite easily blow air through the oil feed with the oil return blocked by my finger. Also it started leaking immediately even on idle so I think the seals were already leaking when it came back from the rebuild....thats if they even rebuilt it and didn't just clean it up!

Theres no oil in the intake side and the max boost is 1.8 bar. I will check the breather - it doesn't run into the inlet any more but into a catch bottle. Should there be an oil restrictor in the oil feed? I'm using the original oil feed pipe with a flexible hose attached to bring it to the different location on the 2259.

[luke1135]

Also planning on changing my clutch next week. Have a pretty good idea what I'm doing but any tips would be appreciated. Would it be worth pulling the engine and gearbox out as one piece or is it not too hard to seperate the box from the engine.

I'm hoping to be able to use one of the servicing bays at work one night so I might have a pit to work in

[adamss24]

Seals are mechanical and work by differences in pressure between inlet and exhaust. The more boost the better they seal. I have a hybrid turbo on my a6 and if i let it idle for 10min or so it will blow a big plume of smoke when setting off. No excessive smoke in normal driving ! I do take the engine off with a clutch but i would do it with the gearbox off if you have a mate or two to help and a transmission jack ! What are you putting in there ? Sachs SRE or genuine ? I have clutch slip with new map as well- clutch is new and slips in 4th, 5th and 6th with +1.9 Bars of boost but i need more fuel supply to VP44 pump ! Them v6 go really well when tuned, took a drive in a mate's standard rs4 b5 and i could keep up with him to 120mph no problem !

[luke1135]

Replacing clutch with a Sachs - I don't think its uprated think its direct replacement for original which has done a lot of miles.
And yes turbo leaks very badly. I have only put the downpipe on at the moment and it leaves a trail of oil across the carpark at work and makes a puddle when I stop...I know because I had to clean it up!

[luke1135]

Don't have a transmission jack but have a few strong lads to help. Will be ok as long as we don't spend 15 minutes fiddling around trying to get it back onto the engine...