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Hey everyone,
Just need a little help in finding a thread that was posted about 3 week ago. The subject matter was addressing an apparent problem that can occur when oil is being poured into a dry sump configuration. If the oil is poured to quickly it can go into the air intake filter.
I have researched this topic in the search criteria for this forum and the Tech/Performance forum and cannot find the discussion that took place. Also I investigated the ducting arrangement of the air intake facility on my 2019 LT1 and I cannot find how any oil can get into the air filter.
So if any one remember this post I am referring to please point me in the right direction.
I am getting my second oil change this coming week.
Thanks.
Hope you all have a great July 4th celebration
Mike
I've never heard that motor oil can get into the air intake by being poured too quickly into the dry sump?
However, It can definitely get into the air intake after driving if dry sump is over-filled.
Is that what you are referring too?
Last edited by Kevin A Jones; 06-29-2019 at 09:30 PM.
It happened to me. If I understand it correctly, my mechanic has a funnel that fits tight in the fill spout and he just up ended two quarts and stuck them in the funnel. If you look at the tank you're filling it has a line that goes directly to the air intake between the air filter and the mass air flow sensor.I think the oil backs up in the tank you're filling and runs to the air filter . when I got home from my oil change oil was running out under my car and I took things apart and found my filter soaked as well as mass air sensor. I checked the oil level and it was not over filled. My tech felt bad about it and I ask if I should drive it to town {20 miles } or if they wanted to haul it back. Next day he showed up at my shop with a new air filter and a lot of shop towels and got it all cleaned up.
It's a shame GM isn't better aware of the abilities of some of the morons working in their dealer "Service" Departments (using the term loosely... very) when they design their vehicles. I bet if equipped with a big enough funnel they could tip up a couple 5-quart jugs in it at the same time. Just think of the results!
Hey everyone,
Just need a little help in finding a thread that was posted about 3 week ago. The subject matter was addressing an apparent problem that can occur when oil is being poured into a dry sump configuration. If the oil is poured to quickly it can go into the air intake filter.
I have researched this topic in the search criteria for this forum and the Tech/Performance forum and cannot find the discussion that took place. Also I investigated the ducting arrangement of the air intake facility on my 2019 LT1 and I cannot find how any oil can get into the air filter.
So if any one remember this post I am referring to please point me in the right direction.
I am getting my second oil change this coming week.
Thanks.
Hope you all have a great July 4th celebration
Mike
Never thought about it until recently when someone posted a pic of a funnel that clamps onto the oil fill opening! If a normal funnel is used the oil can't get above the oil fill opening! That funnel would be fine for a Wet Sump where there is essentially a bottomless pit for the oil to flow. But in a Dry Sump C7 there is a hose (labeled FA in the pic below) that goes from the top of the dry sump tank to the air intake tube. That hose is the reason for the 500 mile oil change in the Dry Sump- details below in SIDEBAR.) So if the dealer used that type of funnel oil could flow to the air intake tube, then air filter, then drip on the ground! (A poster recently posted that his dealer told him after he saw oil dripping from his air cleaner having just had an oil change and said that had happened and to bring his car in to be checked!)
I have done all my own oil changes in my 2014 C7 and now my Grand Sport. I have a wide mouth funnel but the outlet is only about 1 inch OD so it sits on the internal baffles. There are baffles in the dry sump tank. If I pour too fast the oil would come out of the filler neck as the baffles prevent it from flowing fast into the tank.
So if a funnel that clamps onto the filler neck is used and the oil poured quickly, it would rise up above the tank top and go out the "air burping hose" to the air intake. From there, it would run down the air intake tube, soak the air filter and drip on the ground! See below!
SIDEBAR
Understanding why GM requires oil to be changed in a Dry Sump at 500 miles and NOT in a Wet Sump will help clarify the above comments. About 13 months after I got my September 2103 built C7 Z51 GM issued a Bulletin and said 'Dry Sumps" should have their oil changed at 500 miles because oil foam "might occur" with "sustained high engine speed" caused by silicone from curing engine seals depleting the antifoam agents in all oil. That foam "could" transfer with the air from the Dry Sump Tank, and go into the air intake tube. It "could" run down to the air filter and drip on the ground.
To get all oil out of the engine pan the oil/air scavenge pump MUST pump a lot of air! That air MUST be "burped" from the Dry Sump tank (yep just like burping a baby that sucks air with milk!) Since the air can contain some oil mist, the EPA says "No dumping the burped air into the atmosphere, burn it with the engine air." So in a Dry Sump there is a hose from the top of the Dry Sump Tank (labeled FA in my pic. Note: made that pic trying to defined what all the new lines were for the 2017 PCV system that reduced the crankcase oil going into the intake. BTW my measurements so it is half of my 2014 PCV system collected in a "catch can!")
Note there is no such line in a Wet Sump, no burped air no need. So the last line in the GM Bulletin requiring a 500 mile oil change in Dry Sumps olso states, "The oil foam has NO AFFECT on the engine's durability." The only reason for the 500 mile change is to stop oil fouling the air filter dripping on the ground!
From Forum posts, IMO more folks have oil dripping from dealers overfilling dry sumps than from operating their engine at sustained high speed with the first factory fill that "May" have the antifoam agents in all oil depleted from silicone fumes from curing engine seals! Perhaps some have used this clamp on filler funnel, which works fine for 99.5% of the cars/trucks they service because they are wet sumps!
Sorry for the length BUT somethings can't be said in a 280 character Tweet! I understand some only have a 280 character attention span!
Never thought about it until recently when someone posted a pic of a funnel that clamps onto the oil fill opening! If a normal funnel is used the oil can't get above the oil fill opening! That funnel would be fine for a Wet Sump where there is essentially a bottomless pit for the oil to flow. But in a Dry Sump C7 there is a hose (labeled FA in the pic below) that goes from the top of the dry sump tank to the air intake tube. That hose is the reason for the 500 mile oil change in the Dry Sump- details below in SIDEBAR.) So if the dealer used that type of funnel oil could flow to the air intake tube, then air filter, then drip on the ground! (A poster recently posted his dealer called him back after an oil change when he saw oil dripping from his air cleaner and said that had happened and to bring his car in to be checked!)
I have done all my own oil changes in my 2014 C7 and now my Grand Sport. I have a wide mouth funnel but the outlet is only about 1 inch OD so it sits on the internal baffles. There are baffles in the dry sump tank. If I pour too fast the oil would come out of the filler neck as the baffles prevent it from flowing fast into the tank.
So if a funnel that clamps onto the filler neck is used and the oil poured quickly, the oil would rise up above the tank top and go out the "air burping hose" to the air intake. From there it would run down the air intake tube, soak the air filter and drip on the ground! See below!
SDIEBAR
Understanding why GM requires oil to be changed in a Dry Sump at 500 milesand NOT in a Wet Sump will help clarify the above comments. About 13 months after I got my September 2103 built C7 Z51 GM issued a Bulletin and said 'Dry Sumps" should have their oil changed at 500 miles because oil foam that "might occur" with "sustained high engine speed" caused by silicone from curing engine seals depleting the antifoam agents in all oil. That foam "could" transfer with the air from the Dry Sump Tank, and go into the air intake tube. It "could" run down to the air filter and drip on the ground.
To get all oil out of the engine pan the oil/air scavenge pump MUST pump a lot of air! That air MUST be "burped" from the Dry Sump tank (yep just like burping a baby that sucks air with milk!) Since the air can always contain some oil mist the EPA says "No dumping the burped air into the atmosphere, burn it with the engine air." So in a Dry Sump there is a hose from the top of the Dry Sump Tank (labeled FA in my pic. Made that pic trying to defined what all the new lines were for the 2017 PCV system that reduced the crankcase oil going into the intake. BTW my measurements so it is half of my 2014 PCV system!)
Note there is no such line in a Wet Sump. So the last line in the GM Bulletin requiring a 500 mile oil change in Dry Sumps only states, "The oil foam has NO AFFECT on the engine's durability." So the only reason for the 500 mile change is to stop oil fouling the air filter dripping on the ground!
From Forum posts, IMO more folks have oil dripping from dealers overfilling dry sumps than from operating their engine at sustained high speed with the first factory fill that "May" have the antifoam agents in all oil depleted from silicone fumes from curing engine seals!
Thank you for providing all that great information. The content has explained to me all that I need to be conscience of oil fill in the future and why the re-burn is necessary.
^^^
Thanks. Yep, I use a normal funnel with a wide mouth. Can't fill to quickly or it will spill out of the opening! I put a rag around the opening "just in case" so no spilled oil, should it happen, can't run down behind the Dry Sump Tank, where it would be hard to clean. That is also where the cabin air filter is located with a flimsy (IMO) plastic cover. Then when that spilled oil gets hot you'll smell oil for a while!
DANGIT Jerry! I just bought that screw on funnel. No free lunch there haha. I'll keep using the long neck that goes in deeper into the sump. Great info as always bud, THANKS
Original 2014 Z51 rated oil capacity was 10.3 quarts then it was revised down to 9.8 quarts. During a typical oil change, 9.0 quarts will put you dead center between the dipstick marks. I've been using 9.0 ever since my car barfed oil out through the air filter over 40k miles and 5 years ago without issue.
if you have the afm 4/8 c.d. that's where it's coming from that extra oil not burned gets into air intake and t/ body .that's why people are running catch cans good luck
Original 2014 Z51 rated oil capacity was 10.3 quarts then it was revised down to 9.8 quarts. During a typical oil change, 9.0 quarts will put you dead center between the dipstick marks. I've been using 9.0 ever since my car barfed oil out through the air filter over 40k miles and 5 years ago without issue.
I have done all my own oil changes since I got my 2014 Z51 and now my Grand Sport and fill to the center between min and max. But I never was confused with amount as I have only used, “check the dip stick to define how much oil to add.” It says to do that in the 4 volume C7 Service Manual! It states the volume in a table is only an estimate!
However I do it that way because Pop taught me that method over 65 years ago when I started helping him work on cars! It’s the oil level NOT volume that is important.
Yup 3 lines on OIL RESERVOIR, the rear is sidekick oil tank line, the middle is main oil tank line, the front is vent line (how the tanks get air when oil is pulled to/from the engine when needed.
Original 2014 Z51 rated oil capacity was 10.3 quarts then it was revised down to 9.8 quarts. During a typical oil change, 9.0 quarts will put you dead center between the dipstick marks. I've been using 9.0 ever since my car barfed oil out through the air filter over 40k miles and 5 years ago without issue.
I agree, 9.0 quarts puts you right in center of safe area on your dipstick. Even 9.7>9.8 typically puts you slightly above the full mark even though doesn't seem enough over to cause issues.
When I change the oil over for a track fill I put in 10 quarts (which takes the dipstick level to just above the top dot) then add 0.3 of a quart (about 9 oz) to get to the half quart over fill recommended for track driving. Have never gotten oil in the intake and have driven around town with that half quart over fill a number of times before and after going to the track for a few days.
There is a lot of misguided sensitivity to over filling the dry sump cars but small amounts of over fill aren't what cause problems. If you never take your car to the track and the mechanic drains the oil properly and then puts in 10 quarts of the proper oil which will take the level above the top dot there is no reason to demand they FIX the PROBLEM since there really ISN'T a problem.
When I had my 2nd free oil change on my 2017 GS they over filled the tank ( I was way about 1/3 inch over top dot after 10 min from shutting motor off). The reason that I noticed it was because of the oil smell thru my vents. 1st I extracted 1/2 qrt and was still just above the top dot and still smelled the oil so I extracted another 1/2 qrt which left me just above halfway between the 2 dots and the smell went away. I don't know what procedure the mechanic used to drain the oil or fill it.
When I change the oil over for a track fill I put in 10 quarts (which takes the dipstick level to just above the top dot) then add 0.3 of a quart (about 9 oz) to get to the half quart over fill recommended for track driving. Have never gotten oil in the intake and have driven around town with that half quart over fill a number of times before and after going to the track for a few days.
There is a lot of misguided sensitivity to over filling the dry sump cars but small amounts of over fill aren't what cause problems. If you never take your car to the track and the mechanic drains the oil properly and then puts in 10 quarts of the proper oil which will take the level above the top dot there is no reason to demand they FIX the PROBLEM since there really ISN'T a problem.
Bill
Yep, a certain amount of oil over the MAX is specified for Tracking since at high rpm lots of oil is sprayed around the crankcase. BUT just how much "extra" is OK is a question. This is what it says in the Owner's Manual in Several locations:
"CAUTION: Do not add too much oil. Oil levels above or below the acceptable operating range shown on the dipstick are harmful to the engine.If you find that you have an oil level above the operating range, i.e., the engine has so much oil that the oil level gets above the cross-hatched area that shows the proper operating range, the engine could be damaged. You should drain out the excess oil or limit driving of the vehicle and seek a service professional to remove the excess amount of oil."
On Page 165 relative to oil levels while tracking: "Z51 Performance Package, Grand Sport, and Z06 Only: Check the oil level often during track events and competitive driving and keep the level at or near 0.5L (0.5qt) above the upper mark that shows the proper operating range on the engine oil dipstick. After the competitive driving, remove excess oil so that the level on the dipstick is not above the upper mark that shows the proper operating range."
Appreciate your experience indicates it is not been a problem in street driving with 9 oz over the max dot extra BUT also suggest folks follow what it says in the Owner's Manual. There have been many posts where a Dealer has filled with too much oil and it came out through the air vent tube and dripped from the oil filter. Just how much extra oil that takes is not quantified.
However, this Thread has nothing to do with overfilling. It's when filling and using a funnel that clamps onto the oil inlet, like the cap, AND when the funnel is filled quickly the oil level in the funnel will be will above the tank top. Then oil can flow into the air vent hose, run down the air intake tube, soak the filter and drip on the ground.
06-29-2019, 09:09 PM
Dry sump oil fill overflow into air intake
I bet if equipped with a big enough funnel they could tip up a couple 5-quart jugs in it at the same time. Just think of the results!
Since the air can contain some oil mist, the EPA says "No dumping the burped air into the atmosphere, burn it with the engine air." So in a Dry Sump there is a hose from the top of the Dry Sump Tank (labeled FA in my pic. Note: made that pic trying to defined what all the new lines were for the 2017 PCV system that reduced the crankcase oil going into the intake. BTW my measurements so it is half of my 2014 PCV system collected in a "catch can!")
I have done all my own oil changes since I got my 2014 Z51 and now my Grand Sport and fill to the center between min and max. But I never was confused with amount as I have only used, “check the dip stick to define how much oil to add.” It says to do that in the 4 volume C7 Service Manual! It states the volume in a table is only an estimate!
