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Lot of oil coming out from some of the exhaust valves . 4 of the valves are dry . The rest are wet . Sealings are new . Guidings have been changed before some time , the sealings are wery easy to mount ..
Not sure if it could be some cracks innside the head . Before dismantling i did also see lot og oil com out between head and exhaust manifold .
The value guides you said are not new to this engine build. So I guess it was not smoking before?. If you have just changed the stem seal and its doing it maybe its that. Does it smoke only when started up or is it when you rev the engine. Has the crankcase's got a good ventilation system. It's maybe a place to look. Are the value stem seals Audi ones or a after market part. If so are they a good know make. Maybe one or more of the seals hasn't sat on to the guide or the clip/spring has come of the seal. Are all the cylinders smoking or just one. Need to narrow it down. Did the engine blow up before coz it could just be oil in the exhaust system burning off. Hope this helps a little. Best regards Lynn S Guildford.
Previous owners that have overhauled it . No oil problem innside cylindears . Exhaust manifoild was full of oil innside and outside . Smoke when start offcourse and also some when driving .
Worried avoit they changed the guides only by pussing them inn with cold head ?ca the head make some cracks then ? I can see innside exhaust ports that one cylindear can have one sealing look godd other full of oil ..
My old aan head when i removed the 'em i found lot of oil on the ex. Valves. 5 out of 10.replaced stem seals couple
times didnt cure it.the car was burning hell out of oil too.if you have some oil seepage on the valve cover around engine number that's also the clue of badly worn guides and blow by forced it out.i replaced the 20x guides never had the oil seepage ever since.the thing you can measure if the guides are still in the good shape is using dial gauge
measured the valve rock.
How did you check the guides? Head cracked is mostly between the spark plug holes and valves.
Have you checked if the stem seals properly installed and sealed?i couldnt imagine anything else
If you said the oil deposited only on exhaust valves not intake valves.ever checked inside the chamber
If there's some mist of oil inside there?when i had worn guides on each cylinders some had only
One worn out not on both exhaust valves too.checking the valves rock can only reveal the guides condition.
Guides are not old . Seals are gone few miles . Have not dismantled all of them yeat . Spark plugs look dark brown . No black **** on them so i guess there is no oil problem innside engine/inntake .
The strange thing is that on the 20v an specialy this the valve sealning are very easy to turn around and take off .
Lot of oil coming out from them after engine is stopped i think ,lot of oil on exhaust manifold .
How do you find valve guides like new?Get the valve out flush with the valve guide and check play.If you are near 0.5 mm play there is no seal that will last.Audi spec for max play is 1 and 1.3mm.That is a joke,and many others can confirm that,i did not invented the round wheel.
Next to check is the valve stem.Stems can be scratched at removal of valves,instalation and at lapping if not enough lubricant is used or if rules of cleanliness are not applyed.
Lapping compund can get on the stem of the valve and ruin the fine finish of the stem.Or even hone the guide.So oil will be trapped in the scratches like on the cylinder bores.Or if the stem scratches are bigger,the seal lip will be destroyed in fiew passes of the valve up and down.
Regarding to the question of head cracked or head not hot when guides inserted:my opinion is this is the last place to look.What is the dimension of cylinder at TDC and what is the ring gap?
If seats are reworked by hand mill and valves are not new(audi spec no grinding to valves) lapping paste is used,in different grits.
0.5 mm is not a 10000km wear.It is much more.Just hold the valve to one side,close it and feel how valve seat centers it.But in the end,it is your work,your time,do as you consider.
Agreed with Pasbogdan 1mm and 1.3mm regarding the audi wear limits is a joke.you're blowing tons of oil through the valve shafts with that amount of wear lol.one more thing if your guides are worn out,the new stem seals did nothing.they're still leaking the oil though.
As i told you they are "new" i consider if the guys that mount them with cold head eventualy did crack the head into som oil channel . I dont need any info about tollerances ..
1.5mm play at exhaust valves is no problem.... No smoke on my engine with this play...
Something else is causing your oil in exhaust...
My experience only...
Goodluck!
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