Oil in the intercooler. Time for turbo rebuild?
#1
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Oil in the intercooler. Time for turbo rebuild?
Wanted to follow up on a prior thread and post a few more questions and observations, so to speak, on what may causing excessive consumption.
Here's the prior thread with a few details. (Sorry for the crosspost. Posted to the wrong forum)
Anyway, I haven't been driving the car for several months now. It has fresh 5W-50 Mobile-1 in it. That's what I ended up settling on. I may go to Mobile-1 15W-50 for the next change that will no doubt be this summer after spring driving.
At any rate, my plan was to investigate a bit further as to the oil consumption. This is what I know:
I took the intercooler off and made some observations. One side was fairly dry. The other not so much. Here's the video and some pics.
Intercooler intake...
Intercooler intake...
Intercooler out...
I'm inclined to rebuild the turbo based on things I've read and researched, as well as the oil I found. Does this look like enough oil to warrant a turbo rebuild? I can't say there is "puddling" but it's definitely wet. Could a worn out leaky turbo cause smoke on startup?
I also understand that the valve seals may be part of the issue as well, but thinking that will be a bigger job. So I'm leaning towards pulling the turbo out and sending it off, check the AOS, then deal with the seals if a rebuilt turbo doesn't curb some of the oil consumption.
Here's the prior thread with a few details. (Sorry for the crosspost. Posted to the wrong forum)
Anyway, I haven't been driving the car for several months now. It has fresh 5W-50 Mobile-1 in it. That's what I ended up settling on. I may go to Mobile-1 15W-50 for the next change that will no doubt be this summer after spring driving.
At any rate, my plan was to investigate a bit further as to the oil consumption. This is what I know:
- Leakdown compression numbers are 4% - 9% - 2% - 3%. 140psi across all cylinders. Tech remarked on the 9%, but noted it was within range.
- On immediate startup, there is very little smoke but after the car is warmed slightly, at idle, and I rev the motor the oil begins to burn off, and the exhaust can be pretty thick, until it does burns off. It takes about 30-40 seconds or so, if that.
- On startup, it does splatter a mist of oil that I observed on the garage floor.
- When putting it into full boost, an observer noticed no blue smoke, but did detect slight amounts of blackish smoke.
- On hard of the gas deceleration, no blue smoke detected.
- Recent spark plug change, after purchase, the tech said the plugs were fine, except #2 looked like it might be running a little lean.
- There are no oil leaks that leave drips in the garage.
- EDIT: Forgot to mention there is the smell of oil vapor that permeates that cabin when I put it into boost.
I took the intercooler off and made some observations. One side was fairly dry. The other not so much. Here's the video and some pics.
Intercooler intake...
Intercooler intake...
Intercooler out...
I'm inclined to rebuild the turbo based on things I've read and researched, as well as the oil I found. Does this look like enough oil to warrant a turbo rebuild? I can't say there is "puddling" but it's definitely wet. Could a worn out leaky turbo cause smoke on startup?
I also understand that the valve seals may be part of the issue as well, but thinking that will be a bigger job. So I'm leaning towards pulling the turbo out and sending it off, check the AOS, then deal with the seals if a rebuilt turbo doesn't curb some of the oil consumption.
Last edited by kevinr1247; 02-01-2016 at 05:12 PM. Reason: clarification
#2
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You can get into knock down wars on here about what oil to use, but the synthetics molecule size is rather uniform where the dino oil has a larger size differential in the molecules. You may want to try a dino oil like VR-1 20-50 to see if that solves your problem. These motors were never tight tolerance affairs.
I ran a synthetic in my engine but it was recently rebuilt at the time. Rebuilding again now.
I ran a synthetic in my engine but it was recently rebuilt at the time. Rebuilding again now.
#3
Drifting
I would do three things, reseal the valves, re-ring the pistons and rebiuld the turbo. If the turbo has to much shaft play then it should be rebiult or replaced anyways. Also blow by will enter before the turbo and also create an illusion that the turbo is bad when it's not. Along with damaging the impeller blade when it's at 100k RPM's and some oil droplets hit it on full boost. When I had a turbo die on me it dumped oil into the intercooler and it literally poured out a few ounces of oil once removed. It sounds like you have the start of all three happening. Black smoke is running too rich BTW. Blue smoke is oil and white is water.
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It is entirely normal for these cars to be wet with oil throughout the intake tract. Oil vapor/mist from the AOS is routed to the J-boot, downstream of the AFM and upstream of the throttle body, for combustion.
That said, your intercooler does not appear to have excessive oil accumulation. From this, I suspect the compressor side of your turbo is not the problem. More than likely, the seals on the turbine side are wearing, allowing [some] oil into the exhaust tract.
Re: oil consumption...the 5w is simply not viscous enough. And the fact that it's synthetic makes it worse. Before pulling the turbo, I would drain that 5w, refill with 15w/20w, and put some miles on the car.
That said, your intercooler does not appear to have excessive oil accumulation. From this, I suspect the compressor side of your turbo is not the problem. More than likely, the seals on the turbine side are wearing, allowing [some] oil into the exhaust tract.
Re: oil consumption...the 5w is simply not viscous enough. And the fact that it's synthetic makes it worse. Before pulling the turbo, I would drain that 5w, refill with 15w/20w, and put some miles on the car.
#6
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I'd clean out the intercooler by swishing some gasoline/diesel inside of it, let it dry, then run it as normal for a few weeks.
Pull it out again and see how oily it really gets in that time to give you an idea of how bad it might be...
Pull it out again and see how oily it really gets in that time to give you an idea of how bad it might be...
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#8
Drifting
I think you know the answer but don't want it to be true. It's only money. You can't spend it when your dead, so enjoy spending it now. Or you may not want to do the job, hey it's only time out of your life. But over a short time you get it back by being able to drive faster then walking.
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I think you know the answer but don't want it to be true. It's only money. You can't spend it when your dead, so enjoy spending it now. Or you may not want to do the job, hey it's only time out of your life. But over a short time you get it back by being able to drive faster then walking.
I'll start with the valve seals then move on to the turbo, then deal with the exhaust. I've never done it before so I'm in the process of doing plenty of research to know what to expect. For the valve seals, I'm referring to Clark's Garage mainly but I've bookmarked tons of other info.
Wish me luck.
#10
Drifting
Luck? Dude I wish you confidence. If you have any questions ask away. They will be answered. Rennlist has centuries of knowledge thru the listers when added up.
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Okay, continuing research and the plot thickens a bit. Going through the records I found a receipt dated 2004. Looks like they did a complete head refresh at 87k. So, the valve seals were replaced in 2004 at 87k miles. Now it has 104k on the clock. So in 12 years the car has been driven 17k miles. It's obviously been sitting a lot.
Is it common/normal for seals to deteriorate when the car is being stored or sitting for extended periods of time?
Is it common/normal for seals to deteriorate when the car is being stored or sitting for extended periods of time?
Last edited by kevinr1247; 01-30-2016 at 08:53 PM. Reason: clarification
#12
Nordschleife Master
Pull the j-boot off and inspect the compressor of the turbo. If its covered in oil its probably just the AOS.
I suggest making sure the AOS and its associated hoses are in good condition. With that said, also check the oil fill cap seal (commonly overlooked). Pulling the AOS off to replace the commonly leaking o-rings requires turbo removal, so 'while your in there' i would just get the turbo rebuilt. However if its not leaking bad i would just live with it and drive the car. Any vacuum leak from the AOS will cause increased oil consumption.
Fill the intercooler up with gas, swish it around and dump it out. Do this twice to get all the oil residue out. Furthermore install a catch can on the AOS line. This kept the intake track on my car as clean as the day i pulled everything off to clean it. Your intercooler looks typical for these cars.
Typically marginal valve stems will give off blue smoke on decel in gear due to high vacuum, if you saw nothing i wouldnt worry about it. Black is just unburnt fuel, sort of the norm for a turbo. If your getting oil out of the exhaust this is usually oil leaking from the hotside of the turbo.
Note, if your getting oil from the hotside of the exhaust this can be directly related to the AOS. The oil from the turbo is just a natural drain into the crankcase, no pressure or anything forcing it back to the pan. So a vacuum in the crankcase from a good condition AOS system will improve oil drainage.
Also are you running a stock turbo? Most aftermarket turbos require a restrictor on the oil inlet of the turbo otherwise you will blow oil.
I suggest making sure the AOS and its associated hoses are in good condition. With that said, also check the oil fill cap seal (commonly overlooked). Pulling the AOS off to replace the commonly leaking o-rings requires turbo removal, so 'while your in there' i would just get the turbo rebuilt. However if its not leaking bad i would just live with it and drive the car. Any vacuum leak from the AOS will cause increased oil consumption.
Fill the intercooler up with gas, swish it around and dump it out. Do this twice to get all the oil residue out. Furthermore install a catch can on the AOS line. This kept the intake track on my car as clean as the day i pulled everything off to clean it. Your intercooler looks typical for these cars.
Typically marginal valve stems will give off blue smoke on decel in gear due to high vacuum, if you saw nothing i wouldnt worry about it. Black is just unburnt fuel, sort of the norm for a turbo. If your getting oil out of the exhaust this is usually oil leaking from the hotside of the turbo.
Note, if your getting oil from the hotside of the exhaust this can be directly related to the AOS. The oil from the turbo is just a natural drain into the crankcase, no pressure or anything forcing it back to the pan. So a vacuum in the crankcase from a good condition AOS system will improve oil drainage.
Also are you running a stock turbo? Most aftermarket turbos require a restrictor on the oil inlet of the turbo otherwise you will blow oil.
#13
Okay, continuing research and the plot thickens a bit. Going through the records I found a receipt dated 2004. Looks like they did a complete head refresh at 87k. So, the valve seals were replaced in 2004 at 87k miles. Now it has 104k on the clock. So in 12 years the car has been driven 17k miles. It's obviously been sitting a lot.
Is it common/normal for seals to deteriorate when the car is being stored or sitting for extended periods of time?
Is it common/normal for seals to deteriorate when the car is being stored or sitting for extended periods of time?
Bought a car 4 months ago that has sit buy had about $40,000 into it.
The sitting had caused me to replace many things valve stem seals are next cause of oil consumption.
#14
Drifting
Good post.
Pull the j-boot off and inspect the compressor of the turbo. If its covered in oil its probably just the AOS.
I suggest making sure the AOS and its associated hoses are in good condition. With that said, also check the oil fill cap seal (commonly overlooked). Pulling the AOS off to replace the commonly leaking o-rings requires turbo removal, so 'while your in there' i would just get the turbo rebuilt. However if its not leaking bad i would just live with it and drive the car. Any vacuum leak from the AOS will cause increased oil consumption.
Fill the intercooler up with gas, swish it around and dump it out. Do this twice to get all the oil residue out. Furthermore install a catch can on the AOS line. This kept the intake track on my car as clean as the day i pulled everything off to clean it. Your intercooler looks typical for these cars.
Typically marginal valve stems will give off blue smoke on decel in gear due to high vacuum, if you saw nothing i wouldnt worry about it. Black is just unburnt fuel, sort of the norm for a turbo. If your getting oil out of the exhaust this is usually oil leaking from the hotside of the turbo.
Note, if your getting oil from the hotside of the exhaust this can be directly related to the AOS. The oil from the turbo is just a natural drain into the crankcase, no pressure or anything forcing it back to the pan. So a vacuum in the crankcase from a good condition AOS system will improve oil drainage.
Also are you running a stock turbo? Most aftermarket turbos require a restrictor on the oil inlet of the turbo otherwise you will blow oil.
I suggest making sure the AOS and its associated hoses are in good condition. With that said, also check the oil fill cap seal (commonly overlooked). Pulling the AOS off to replace the commonly leaking o-rings requires turbo removal, so 'while your in there' i would just get the turbo rebuilt. However if its not leaking bad i would just live with it and drive the car. Any vacuum leak from the AOS will cause increased oil consumption.
Fill the intercooler up with gas, swish it around and dump it out. Do this twice to get all the oil residue out. Furthermore install a catch can on the AOS line. This kept the intake track on my car as clean as the day i pulled everything off to clean it. Your intercooler looks typical for these cars.
Typically marginal valve stems will give off blue smoke on decel in gear due to high vacuum, if you saw nothing i wouldnt worry about it. Black is just unburnt fuel, sort of the norm for a turbo. If your getting oil out of the exhaust this is usually oil leaking from the hotside of the turbo.
Note, if your getting oil from the hotside of the exhaust this can be directly related to the AOS. The oil from the turbo is just a natural drain into the crankcase, no pressure or anything forcing it back to the pan. So a vacuum in the crankcase from a good condition AOS system will improve oil drainage.
Also are you running a stock turbo? Most aftermarket turbos require a restrictor on the oil inlet of the turbo otherwise you will blow oil.
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This is going to sound like rather pedantic question I know, but I'm trying to do as much prep work as I can, to make the job as smooth as possible....if possible.
To get at the 6mm hex turbo mounting bolts which tool is preferable, you think? I've found two options. This one:
or this one...
https://www.pegasusautoracing.com/pr...sp?RecId=12147
To get at the 6mm hex turbo mounting bolts which tool is preferable, you think? I've found two options. This one:
or this one...
https://www.pegasusautoracing.com/pr...sp?RecId=12147