Help tiny stream of fresh oil coming out tailpipes after oil change
03-12-2022, 05:23 PM
#1
Registered Member
Thread Starter
tiny stream of fresh oil coming out tailpipes after oil change
Its been doing this for the past 2 oil changes, and its kind of weird. After doing an oil change, a tiny but faint stream of fresh oil comes out the tailpipes. it doesnt last long, eventually itll stop doing it, and the exhaust pipes actually remain quite clean for a respectable amount of time. My question is, why is it doing this, and why is it doing this only on fresh oil. Any ideas?
03-14-2022, 08:59 AM
#4
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Thread Starter
03-14-2022, 10:48 AM
#5
I'm tagging @BULL here as he knows this system better than I. Typically, whenever oil is passed through to the exhaust, barring serious engine issues, the most common cause could be tied to a clogged/ faulty PCV valve.
How much oil loss do you estimate and does the blue smoke eventually burn off or persist?
How much oil loss do you estimate and does the blue smoke eventually burn off or persist?
03-14-2022, 11:06 AM
#6
Registered Member
Thread Starter
I'm tagging @BULL here as he knows this system better than I. Typically, whenever oil is passed through to the exhaust, barring serious engine issues, the most common cause could be tied to a clogged/ faulty PCV valve.
How much oil loss do you estimate and does the blue smoke eventually burn off or persist?
How much oil loss do you estimate and does the blue smoke eventually burn off or persist?
03-15-2022, 09:15 AM
#7
Moderador
That's pretty weird. A picture would help tremendously.
Sounds like you've narrowed down the event at least.
I take it you are doing the oil changes?
How much oil do you collect back in your changes + what you collect in the can?
Thinking out loud here, the only thing it makes sense to me is that while the engine is off and you are putting in oil the oil carries one heavy and thick volume, this volume is now entering the crank case and forcing air out, as this air forces out it will come out of the oil cap hole as well as the breather since the PCVs will be closed, with open PCVs air would come out of this area as well.
If it indeed is oil, it means its happening while the engine is off.
By any chance what are you oil filling practices? Do you use a small funnel and slow pours? do you have a fitting funnel and pool the oil into the funnel? how fast are you dumping fresh oil into the crank case? Do you empty your cans as well?
I ask this because this air many of you have felt this, you can see how much of a difference in pour speed and air coming out just by lifting the funnel.
It's possible that something/catch cans might be introducing some of this during the filling process is my assumption, nothing other than crank case ventilation could do this. Maybe change your oil pouring techniques to a small funnel/ slow pour and see if you notice any differences.
PS: another rare occurrence could be bad oil control rings if its not PCV related, this same pressure could be pushing oily air past the oil control rings of the pistons that are at TDC or close to it (pistons at TDC have a looser piston to wall clearance) This is something that would show regardless of engine on/off though.
Sounds like you've narrowed down the event at least.
I take it you are doing the oil changes?
How much oil do you collect back in your changes + what you collect in the can?
Thinking out loud here, the only thing it makes sense to me is that while the engine is off and you are putting in oil the oil carries one heavy and thick volume, this volume is now entering the crank case and forcing air out, as this air forces out it will come out of the oil cap hole as well as the breather since the PCVs will be closed, with open PCVs air would come out of this area as well.
If it indeed is oil, it means its happening while the engine is off.
By any chance what are you oil filling practices? Do you use a small funnel and slow pours? do you have a fitting funnel and pool the oil into the funnel? how fast are you dumping fresh oil into the crank case? Do you empty your cans as well?
I ask this because this air many of you have felt this, you can see how much of a difference in pour speed and air coming out just by lifting the funnel.
It's possible that something/catch cans might be introducing some of this during the filling process is my assumption, nothing other than crank case ventilation could do this. Maybe change your oil pouring techniques to a small funnel/ slow pour and see if you notice any differences.
PS: another rare occurrence could be bad oil control rings if its not PCV related, this same pressure could be pushing oily air past the oil control rings of the pistons that are at TDC or close to it (pistons at TDC have a looser piston to wall clearance) This is something that would show regardless of engine on/off though.
Last edited by BULL; 03-15-2022 at 09:24 AM.
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03-15-2022, 09:26 AM
#8
Registered Member
Thread Starter
That's pretty weird. A picture would help tremendously.
Sounds like you've narrowed down the event at least.
I take it you are doing the oil changes?
How much oil do you collect back in your changes + what you collect in the can?
Thinking out loud here, the only thing it makes sense to me is that while the engine is off and you are putting in oil the oil carries one heavy and thick volume, this volume is now entering the crank case and forcing air out, as this air forces out it will come out of the oil cap hole as well as the breather since the PCVs will be closed, with open PCVs air would come out of this area as well.
If it indeed is oil, it means its happening while the engine is off.
By any chance what are you oil filling practices? Do you use a small funnel and slow pours? do you have a fitting funnel and pool the oil into the funnel? how fast are you dumping fresh oil into the crank case? Do you empty your cans as well?
It's possible that something/catch cans might be introducing some of this during the filling process is my assumption, nothing other than crank case ventilation could do this.
Sounds like you've narrowed down the event at least.
I take it you are doing the oil changes?
How much oil do you collect back in your changes + what you collect in the can?
Thinking out loud here, the only thing it makes sense to me is that while the engine is off and you are putting in oil the oil carries one heavy and thick volume, this volume is now entering the crank case and forcing air out, as this air forces out it will come out of the oil cap hole as well as the breather since the PCVs will be closed, with open PCVs air would come out of this area as well.
If it indeed is oil, it means its happening while the engine is off.
By any chance what are you oil filling practices? Do you use a small funnel and slow pours? do you have a fitting funnel and pool the oil into the funnel? how fast are you dumping fresh oil into the crank case? Do you empty your cans as well?
It's possible that something/catch cans might be introducing some of this during the filling process is my assumption, nothing other than crank case ventilation could do this.
basic image here, its literally just a tiny film, and it goes away after like 1 drive, its really not alot of oil, but enough to create a drop or 2 on my driveway when on a slant
03-15-2022, 09:42 AM
#9
Moderador
long narrow funnel, fill pretty fast, i do empty catch cans, i collect about the 5 quarts back.
basic image here, its literally just a tiny film, and it goes away after like 1 drive, its really not alot of oil, but enough to create a drop or 2 on my driveway when on a slant
basic image here, its literally just a tiny film, and it goes away after like 1 drive, its really not alot of oil, but enough to create a drop or 2 on my driveway when on a slant
Do you have cats?
05-08-2022, 04:09 PM
#10
Registered Member
Thread Starter
I have HFC
tips are clean now, I dont have problems, why is there a byproduct, it just seems very odd, and shouldn't be happening
I know I should change my VC gasket, im at 161K miles and definitely should be done, but besideds that, would it be any other issue? Oil level seems normal on the dip stick (on fresh oil change too)
Im not like burn burning oil like a kia or something, but I think its atleast a little cause worn gaskets. tried the oil posted from my catch can thread, the mobil 1 ext perf HM, to see if I can swell up the seals to last me a little longer, as a VCG job is like, $600 unless i DIY it, which I might
05-09-2022, 03:30 PM
#11
Moderador
been a while since ive been on here;
I have HFC
tips are clean now, I dont have problems, why is there a byproduct, it just seems very odd, and shouldn't be happening
I know I should change my VC gasket, im at 161K miles and definitely should be done, but besideds that, would it be any other issue? Oil level seems normal on the dip stick (on fresh oil change too)
Im not like burn burning oil like a kia or something, but I think its atleast a little cause worn gaskets. tried the oil posted from my catch can thread, the mobil 1 ext perf HM, to see if I can swell up the seals to last me a little longer, as a VCG job is like, $600 unless i DIY it, which I might
I have HFC
tips are clean now, I dont have problems, why is there a byproduct, it just seems very odd, and shouldn't be happening
I know I should change my VC gasket, im at 161K miles and definitely should be done, but besideds that, would it be any other issue? Oil level seems normal on the dip stick (on fresh oil change too)
Im not like burn burning oil like a kia or something, but I think its atleast a little cause worn gaskets. tried the oil posted from my catch can thread, the mobil 1 ext perf HM, to see if I can swell up the seals to last me a little longer, as a VCG job is like, $600 unless i DIY it, which I might
Are you still seeing any oil? I take it you're about to change the oil soon?
05-09-2022, 03:48 PM
#12
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