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View Full Version : Blown Turbos ?? Please Help !!



Jimmy Joe
October 23rd, 2011, 07:10
I would very much appreciate your comments /advise on this issue that might be a problem.
I had a leak on the Radiator (already fixed) which led to the disassembly of the whole front end, upon which I noticed dark oil stains at the base of both intercoolers, so I had them removed. The insides were clean with no leaks, the oil stains were coming from the big pipes leading from the turbos to the intercoolers, (inlet tract), in all, no more than three spoons, a bit more on the drivers side. Before disassembly, the car ran fine, perhaps a little hesitation sometimes at tip-in, but no alarm lights on the dash (other than the low cooling level that led to disassembly), no loss of power, no strange noises, nothing. I donīt know if a small amount of oil on this pipes is normal is normal or could lead to a later failure. Car has 24, 860K supposedly original miles. Your help would be very appreciated.

Thank you very much.

hahnmgh63
October 23rd, 2011, 08:19
Normal amount of oil, no worries. A slight amount of the oil may be from the Turbo oil seals but most of it is just crankcase ventilation oil pumped back into the intake just upstream of the Turbos. Turbo cars tend to generate more crankcase ventilation due to the higher crankcase pressures and blow by pressures, especially if driven hard (more boost is like raising compression ratio). I uses the Aces IV and two oil catch cans on both banks so my Intercoolers were very clean last time I looked. The normally Audi procedure in the maintenence interval has the dealer cleaning the intercoolers every few services.

kismetcapitan
October 23rd, 2011, 08:54
if you blow a turbo, you'll know it. HUGE loss of power, massive white clouds of smoke billowing from the tailpipe. It's not a subtle death, trust me!

ben916
October 23rd, 2011, 09:29
if you blow a turbo, you'll know it. HUGE loss of power, massive white clouds of smoke billowing from the tailpipe. It's not a subtle death, trust me!

And some strange noises of non-linear turbo sounds...

SzymekCRX
October 23rd, 2011, 09:45
I would very much appreciate your comments /advise on this issue that might be a problem.
I had a leak on the Radiator (already fixed) which led to the disassembly of the whole front end, upon which I noticed dark oil stains at the base of both intercoolers, so I had them removed. The insides were clean with no leaks, the oil stains were coming from the big pipes leading from the turbos to the intercoolers, (inlet tract), in all, no more than three spoons, a bit more on the drivers side. Before disassembly, the car ran fine, perhaps a little hesitation sometimes at tip-in, but no alarm lights on the dash (other than the low cooling level that led to disassembly), no loss of power, no strange noises, nothing. I donīt know if a small amount of oil on this pipes is normal is normal or could lead to a later failure. Car has 24, 860K supposedly original miles. Your help would be very appreciated.

Thank you very much.

As others say - don't worry. I was terryfied as well when opened one of my intercoolers and found oil inside... :)

kismetcapitan
October 23rd, 2011, 11:35
cleaning oil out of intercoolers is routine maintenance. With front-mounted intercoolers and big-power engines, it's not uncommon to have oil practically gushing out when you turn it over to empty it!

aussie rs6
October 23rd, 2011, 19:13
cleaning oil out of intercoolers is routine maintenance. With front-mounted intercoolers and big-power engines, it's not uncommon to have oil practically gushing out when you turn it over to empty it!

forgive my ignorance, but if hypothetically emmissions controls were not in effect, to prevent oil getting into the inlet stream and intercooler via the current positive crankcase ventilation, would it not be better to have the crankcase/rocker covers vent straight to a catch can vented to the atmosphere? This might leave oil vapours floating around inthe engine spaces, but at least they would not get into the inlet stream.

Alternatively a separate suction pump connected to the rocker covers venting to a catch can would achieve the positive crankcase ventilation effect and should remove all oil vapours from the engine spaces?
A cheap form of vacumn pump would be a venturi hose exposed to the airstream under the car as per the high school lab water jet vacumn pump.

Jimmy Joe
October 23rd, 2011, 22:08
Thank you, thank you, thank you guys, I can breath again. I was bracing myself for a real expensive investiment on new or rebuilt turbos. I am performing all the maintenance by the book with the help of my indie mechanic, which is quite good bud doesnīt have any experience with RS6, so we go by the Bentley manual and the invaluable help of the friends on this forum. Plan to buy a VAG COM. soon and learn to use it , Thanks again.

hahnmgh63
October 23rd, 2011, 22:55
Jimmy Joe, if you pull the plastic engine belly pan off and remove the lower intercooler hoses you can drain any oil out of the intercoolers, then just take some spray Brake cleaner and spray up into the intercoolers to rinse some of the extra oil residue out. When you re-install the lower intercooler hoses make sure you wipe all of the oil off the inside of the hose where it goes over the intercooler hose flange or else it may slip off under boost. A rag wetted with a little break clean does the job well.

Aussie RS6, similar but instead of venting to the atmosphere I run inline oil catch cans, one on each bank. They have the metal bristly sponge material in them to help the oil vapors to condense as the air pressure pushes through the can and back on its way to the inlet track. It obviously doesn't take all of the oil out of the system but there is always a small pool of oil in each catch can when I clean them at every engine oil change, and my intercoolers stay fairly clean when I have pulled the lower intercooler hose to inspect them.

kismetcapitan
October 23rd, 2011, 23:43
not sure if this can be done with our V8s, but on my Skyline, I use a oil separator, which works similarly to the abovementioned system, but the oil condensate is drained into the oil return lines from the turbos, which are not under pressure. The system is vented to the atmosphere instead of recirculating back into the intakes (which is how the engine was originally designed; I plugged off the oil recirculation system to the intakes), through a tube that runs under the car and exits under the rear bumper. Not eco-friendly, but it keeps the oil in my intake pipes down, and recycles much of the oil that would otherwise be caught and thrown out in catch cans.

Brav
October 24th, 2011, 00:48
not sure if this can be done with our V8s, but on my Skyline, I use a oil separator, which works similarly to the abovementioned system, but the oil condensate is drained into the oil return lines from the turbos, which are not under pressure. The system is vented to the atmosphere instead of recirculating back into the intakes (which is how the engine was originally designed; I plugged off the oil recirculation system to the intakes), through a tube that runs under the car and exits under the rear bumper. Not eco-friendly, but it keeps the oil in my intake pipes down, and recycles much of the oil that would otherwise be caught and thrown out in catch cans.

That is basically what I use for my Noble.