Apologies misread your post, yes intercooler ok to have some oil in it, obviously thought not excessive amounts.
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A little smoke
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Apologies misread your post, yes intercooler ok to have some oil in it, obviously thought not excessive amounts.
I am losing a little of what you are saying, with no punctuation marks?
Head gasket leaks are usually hairline cracks, in the vast majority of cases this would not cause any unfavourable readings on a compression check, when they are very bad they do, but you are talking losing all your coolant bad!
paul-murphys
efr 6758 here i come
not losing any coolant an in 10k have put 1litre of oil in only. Is there a way you can check the turbo. The performance feels ok don't feel like losing power. Payed mechanic 40 quid to do a compression test an he said everything i the head would be ok. I said about stem seals an he said would lose compression. Help 
You need to change your mechanic, the stem seals leak oil down the stem of the valve and the oil drops into the cylinder when the valve opens, usually at it's worst on startup and has no effect on the compression levels of the cylinder!
I would say look at the breather system, the only way to check the turbo is to remove the TIP and gently check for play on the impellor shaft?
I would say look at the breather system, the only way to check the turbo is to remove the TIP and gently check for play on the impellor shaft?
paul-murphys
efr 6758 here i come
ok thanks. Do you no how many pipes got to check. I can't see how a blocked pipe would cause this smoke though. Where does this pipe go to? Its really confusing me
I am inexperienced with leons so some other experienced members may be able to answer your questions re pipewrok/breather system?
But I would imagine doing a run with a vagcom would let you know if you had a boost leak from a torn pipe, or the other option is to do a boost leak check with compressed air?
A blocked pipe can cause smoke because the engine has a system in it to purge oil vapour from the sump, if that is faulty then the engine can suck in oil vapour burning it in the chamber.
But I would imagine doing a run with a vagcom would let you know if you had a boost leak from a torn pipe, or the other option is to do a boost leak check with compressed air?
A blocked pipe can cause smoke because the engine has a system in it to purge oil vapour from the sump, if that is faulty then the engine can suck in oil vapour burning it in the chamber.
a compression test showed faulty vavle on exhaust side. it never smoked on start up
Hang on who has the problem and on what car
im saying that i was advised to get the test done, 1st cylinder was down and when head came off valve stem seals were shot. bore wear was minimal. i was told suspected stem seals when the guy did the test along with possible rings. it was leaking from somewhere and it wasnt the rings?
Stem seals do not make up any of the seal that gives compression, if a valve is knackered and not seating correctly or bent out of true it can then cause the seal to leak.
But all the seal does is stop oil dripping from the head down the valve and into the cylinder.
But all the seal does is stop oil dripping from the head down the valve and into the cylinder.
they also mentioned somthing about a pressure difference when the car was at idle? i mean within the head causing the oil to enter via a bad stem seal. it was part explanation as to why it only smoked on idle
It would smoke on idle with a bad stem seal, as the seal lets by the oil runs down the valve and into the cylinder or burnt off with exhaust gases.
Onthebench
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Stem seals will NOT show up on a compression test - FACT! The stem seals are outside of the closed environment of the cylinders. Yes they will give smoke under certain conditions, including idle BUT the time they show the most is on a cold start. Under idle, there is a much higher vacuum in the cylinders on the intake stroke (due to closed throttle flap) and when the intake valve opens this vacuum is then presented to the stem seals which causes the pressure difference mentioned by your mechanic. The ONLY time that stem seals can cause a problem is while the valve is OPEN - ie not during the compression cycle....
Sorry if this doesn't make much sense, please ask if there is anything unclear
Cheers,
Andy
Stem seals will NOT show up on a compression test - FACT! The stem seals are outside of the closed environment of the cylinders. Yes they will give smoke under certain conditions, including idle BUT the time they show the most is on a cold start. Under idle, there is a much higher vacuum in the cylinders on the intake stroke (due to closed throttle flap) and when the intake valve opens this vacuum is then presented to the stem seals which causes the pressure difference mentioned by your mechanic. The ONLY time that stem seals can cause a problem is while the valve is OPEN - ie not during the compression cycle....
Sorry if this doesn't make much sense, please ask if there is anything unclear
Cheers,
Andy
the mans talking sence
pressurised system on idle will draw oil though a perished seal as with every engine it try's to suck co2 from every available orrifice.. when running it makes up the compensation through the inlet . compression test wont show stem seal fault and neither will any vag com test as there isnt a sensor on the seals as its imposible to know unless you pull the engines head off ! as in the ford CVH engine (prone to stem seal wear ) How much oil smoke is being emitted on idle and over run ???
paul-murphys
efr 6758 here i come
nice audio - little... big...
The one i went to see for sale today did the same, but worse. One of the many reasons i walked away.
The one i went to see for sale today did the same, but worse. One of the many reasons i walked away.
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