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[pulsarboby]

right as some of you are aware i have a problem with my car kickin out a puff of blue smoke on deceleration, after rebuilding my engine!

it was pointed out to me by a top mechanic mate of mine that he is 99% sure turbos kaput, but this is the second rebuilt turbo by essex turbos!:?
took car out for a run yesterday and thought i would drive it hard all the way upto 7k rpm and harsh deceleration.
the car is balistically fast,:shock: :shock: considering it hasnt bedded in yet properly, and pulls very strongly on boost in every gear, so no probs there!

what i need to know, and surely someone out there whos clever enough can answer this question is:
he stated if the turbo wasnt kaput, how could blue smoke (burning oil) escape past the exhaust impellor outer oil seal on turbo, as all the exhaust gases have to go through the turbo to drive the impellors, IF the oil seal wasnt knackered?

heres the brain cruncher though! if that oil seal wasnt knackered then no turbo car should smoke as the seal would stop any oil escaping past it, so if you had a ring gone, how would oil get past the seal and cause blue smoke?

i think hes wrong, wrong, wrong as the burning oil would turn to gas formation before it goes through turbo, and hence come out as blue smoke, otherwise in theory no turbo driven car even with a naf engine (but good turbo) would ever smoke, as the oil seal would stop any smoke / oil

which brings me to ask then how come my so called top mechanic mate can be so sure it is the turbo and eliminate everything else, when in theory it could be a simple case that the rings just arent bedded in yet, and letting bye a small amount of oil which would come out of exhaust as blue smoke on deceleration???

who thinks im right! and this guy is talking out his ass?

sorry its a bit of a boring thread but some of you may find it interesting, or usefull if a mechanic points his finger at your turbo, when in fact your turbo may be fine and the problem could lay elsewhere, as i think it does in my case, but then theres always the possibility that im wrong and hes right!

 

[huu-raa]

your theory could work have you known anyone else with the same issue?

 

[pulsarboby]

no, it just puzzles me that this problem has always been there ever since i bought the car, and is still there now, its like theres a blue smoke cloud thats haunting me and watching over me where ever i go!
perhaps ive upset the gtir god and this is my pennance for thrashing the car and being a knob!

 

[Keira]

what i need to know, and surely someone out there whos clever enough can answer this question is:
he stated if the turbo wasnt kaput, how could blue smoke (burning oil) escape past the exhaust impellor outer oil seal on turbo, as all the exhaust gases have to go through the turbo to drive the impellors, IF the oil seal wasnt knackered?

if oil is getting past the rings, valve stem seals the turbos oil seal will have no effect on it.

heres the brain cruncher though! if that oil seal wasnt knackered then no turbo car should smoke as the seal would stop any oil escaping past it, so if you had a ring gone, how would oil get past the seal and cause blue smoke?

the seals on the turbos centre housing, prevent oil from the bearing section leaking past the shaft and either getting to the exhaust housing or the comp housing.

Exhaust gases do not pass through the centre housing.

otherwise in theory no turbo driven car even with a naf engine (but good turbo) would ever smoke, as the oil seal would stop any smoke / oil

wrong, if you blow a ringland, scuff a bore, damage a ring or any other thing like a dodgy valve stem seal that allows oil to get anywhere into the combustion chamber and then the exhaust, anywhere from the head down to the exhaust it will smoke. At no point does the expelled exhaust have to pass through the turbo's oil seal, it will go straight past the turbine and any oil will be burned or be burned in the chamber.

a rather broad generalisation and without reeling off all the ifs, buts and whys. but if its bad seals on the turbo, if you leave the car idling for a few minutes and then drive away you will smoke the ****ing street out. The seals can open slightly and oil seeps into the exhaust, under boost the pressure forces everything tight and the car doesn't smoke, same when you back off, the pressures change, oil seeps through...

if its always done it ever since you've owned the car i'd be inclined to think theres a problem that isn't going to go away by itself.

 

[pulsarboby]

thanks so what i thought is right then kieron, and this guys wrong!

all im saying now is that it is a strong possibility that the rings have not yet bedded in sufficiently hence some oil getting past rings and getting into exhaust manifold.

the problem could have been there before due to other causes ie turbo originally fcuked and or worn engine! but it will still give the same symptoms of smoke that im getting now, if you know what i mean!

think i will just keep running it in and see what happens once ive done a few hundred miles in it, if theres still smoke then, then the prob must lie somewhere else!
cheers for the help though chaps, much appreciated

 

[Odin]

I think Kieron was calling you a dumbass in a long winded mannor :lol: :lol: :lol: :lol: :lol: :lol: :lol: .




Rob

 

[pulsarboby]

:shock: no! he is confirming what i thought in the first place, that a turbo oil seal has nothing to do with worn rings, valve stem oil seals etc! it will not stop smoke / burning oil from entering the exhaust chamber from the engine so:nerner:

 

[Odin]

so:nerner:

My money's still on dumbass buddy :lol: :lol: :lol: :lol: :lol: :lol: .







Rob

 

[pulsarboby]

cant see how you can think that, you obviously aint got your reading specs on:-D read it again, hes saying my matey mechanic is wrong and im right!
your getting confused in your old age robbie:roll:

kieron come back and clarify for robbies sake please;-)

 

[gtirx2]

Have you checked your plugs yet mate to see if it is burning much oil?Also you may want to compression check it to see what is going on it maybe just on one cylinder that has not bedded in right yet??You never know it could still be the turbo so if a compression check comes up all clear i would start looking at the blower.I think you want about 150psi on wiseco pistons with a 1.2mm head gasket as that is what mine comes out at;-) .Hope you sort it soon mate:?

 

[pulsarboby]

not checked them yet, maybe a good idea though to do a compression check as you suggested, may shed some light on it!

 

[Fast Guy]

If you've just had the engine rebuilt, I'd hope your mechanic mate is right or it means your newly built engine is the cause of the smoke, so strip down and rebuild again time;-)

 

[pulsarboby]

built lump myself!
but hes not right as kieron has stated, and it isnt necessarily a bad thing as it has only covered 60 miles since rebuild so rings wont be bedded in yet which could cause smoke!
thats what im hoping anyway, if not and turbos fine then ive got big problems awaiting me!

 

[Fast Guy]

New cars don't tend to smoke (that I've seen) before the rings bed in fully.


Did you replace the valve guides?

 

[R called Jay]

Change the turbo for a known good working order one and rule it out.
I don't think you're mechanic quite grasps it unless somethings gone wrong in the translation.
But i'd love a turbo that eliminates any burning oil ;-)

 

[pulsarboby]

yep valve stem oil seals done, ive renewed everything! new car engines are run in on bench nowadays!

and jay just spent £400 having turbo rebuilt, surely cant be that, but after ive run it in done compression check etc if probs still there then im gonna have to take a good look at that turbo, and if faulty go kick some rebuilders ass

 

[cojack]

No the seals dude the valve guide the brass inserts in the head maybe there's a crack in 1 of them and it's expanding due to the heat.

I had a smoking problem om my old xr2 tt. It smoked on the over run like you say also had a puff of smoke when changing gear the turbo had just had a new core at turbo technic's. On the exhurst side it used to drip oil. which was not right i battled with them for ages over this telling them they were at fault but they would not have it.:evil:

It turned out that when i stripped it my self cos i was not sending them the car again they had put the exhurst manifold on the wrong way as this is possible on a cvh and it was restricing int ports on the head. Therefore causing back pressure making the thing smoke. :?

So when i got the turbo back at my expense again. Built it back up and hey presto no smoke and no oil coming past the turbo seals. Did i get my moeny back when i rand them back to tell them it was sorted did i ****.:evil:

Good luck sorting it fella hope it's not as bad as my luck was.;-)

 

[pulsarboby]

its a possibility regarding the valve guides, although i sincerely hope your wrong as ive had the head ported and polished at great expense, good thinking though matey

 

[cojack]

Maybe there's your problem whoever ported your head may have been a bit rough and taken out a guide whilst doing it. Did you notice if they had been cut back. I have seen some ppl do this whilst porting??

 

[pulsarboby]

gotta be honest mate i didnt check that closely, as it came from one of the top porters in the country, really, really hope your not right if thats the case i aint gonna be a happy bunny!