VERY serious oil consumption

[Fastblack]

OK - Qctavia Mk1 - 197k miles.  New head gasket and radiator/coolant system etc approx 10'000 miles ago.  Now drinking oil a approx 1 litre per 250 miles.  Help!!!

 

[KenONeill]

Smoke? If so, what colour?

[Ootohere]

What kind of help do you need?

  The phone number of the place that did the work last time, or someone new, a breakers yard for another engine, 

or crowd funding to get you a new car?

[Jux]

Consuming oil at that rate I would suspect turbo. Pop the inlet pipe off the turbo and check for play in shaft. Not necessarily connected to previous work, a fault with head gasket would have presented itself before 10k

[Fastblack]

Smoke is blue/grey on start up, not really noticeable when driving, unless when changing gear when accelerating onto a dual carriageway, for example, in which case I can sometimes see a puff of black in the mirror.

No signs of external leakage whatsoever.

 

It's never been fast but now seems to lack power even more......

 

Had car for 2 years and its always smoked when starting and used a bit of oil, but nothing like this.  Done over 60k miles with little work required apart from cooling system/cambelt/head gasket/radiator last October. 

Not familiar with diesel engines - can a compression check be done easily enough?

 

Why you suspect the turbo? Can you explain that ?

 

cheers for help so far.

 

Oh, garage who did the work is tried and tested so I have faith in them

Edited 23 March, 2017 by Fastblack

[Saints92]

Blue smoke = oil in exhaust. Most common situation is the turbo seals leaking, and putting oil into the turbo and through the exhaust.

 

If you get it everytime you put the foot down and make the turbo work hard, then it sounds very much like thats your problem.

[KenONeill]

^Agreed.

 

The black on changing up is probably transient over-fuelling and not relevant to the oil consumption issue.

 

Compression testing a diesel is about the same as for a petrol, except that you need a much higher pressure tester (and using one for a petrol engine runs the risk of denting the inside of the bonnet when it is launched by the compression). However, I don't think that's necessary here, because the most likely issues are turbo or valve stem oil seals.

[bigjohn]

Check crankcase breathing? If engine crankcase excessively pressurised oil will blow past the valve oil seals.

 

Also check the "blow" and/or downstream from exhaust  side of the turbo for excessive oil contamination (failed oil seals)

Edited 24 March, 2017 by bigjohn

[Fastblack]

Mechanic says turbo is shot and requires replacement, also there is a lot of pressure building up in the crankcase when engine hot.

 

Says new turbo may or may not solve problem due to suspected worn rings/bores.    Boo.

 

Now has 201k miles so possibly not worth all the work    

 

 

 

[KenONeill]

@Fastblack Your mechanic's comments are still worst case; he's assumed a shot turbo and worn bores. Unless he's done a dry and wet compression test that's not necessarily valid.

 

If he hasn't then you could still have cheaper/simpler problems to fix in the forms of a bunged up crankcase breathing system and a sticky turbo (see stickies and Octavia guides sub-forum).

[Fastblack]

Thanks for that @KenONeil - I'll have a look there.....in the meantime I've acquired a Mk1 vRS estate to go along with it

Edited 18 May, 2017 by Fastblack