Baked on oil: plugs #5 and #6

#1
Hey all, just recently joined. Bought an '05 TB with 94k on it last week. I really went over it before I bought, crawled all around underneath etc.
test drive very nice. BUT we went to pick it up after my wife had the title transferred: I watched in my rearview as she fired it up, big cloud of smoke. I'm like oh no...
we contacted the PO who supposedly called his mechanic and was advised "it's been sitting/short trips and it will clear up once driven" .
The next day I check the oil and it's not even on the stick (showed ok on test drive day but the vehicle wasn't level.
I fill it up and drive it to work, 60mi round trip. Seems great no smoke.
This weekend I pull the plugs. A.C. Iridiums. All look good except 5 and 6. They look like they are burning oil to me, I'll get a pic. I put new A.C. Iridiums in and cleaned the TB which looked to be recently done.
Havent driven it yet, waiting on paint to dry (I repaired the door bottom and front of the hood rust).
I've searched here and oil burning doesn't seem to be common with the i6.
More interesting info: the P.O. said "new head and timing belt". I checked it over and it doesn't look like the head has been off to me, although the bolt that holds the emission hoses on the back of the head is missing, and some wire harnesses were unclipped, so some work has been done.
He didn't seem to know about cars, so I saw a new valve cover gasket and serp belt and figured that's what he meant.

Sorry for the novel. I guess one more thing I'll check is if there is vacuum on the double 90 hose between the valve cover and the resonator.

Any other ideas? Thanks for all of the info here.
 

MRRSM

Lifetime VIP Supporter
#2
Welcome to GMTN Mr. “E” …

Here are a few suggestions:

To get more familiar with the GMT360 Platform… and the GM Atlas LL8 4.2L Engine in particular… Start at the very top of this section with a fresh cup of coffee and a careful read of the FAQ here:

https://gmtnation.com/forums/threads/faq-vortec-4-2l-i-6.17025

Next… follow the instructions provided by @Mooseman ‘s Classic Library of GM OEM Digital Shop Manuals...and download the flavor most suited for your particular vehicle...from here:

https://gmtnation.com/forums/threads/need-service-manuals-get-them-here.361/

As for the present questions about “Oily Plugs”...The Atlas LL8 Engine has a Positive Crankcase Ventilation System in compliance with EPA requirement to collect Crankcase Oily Vapors that fill the motors interior under the pressure of Piston Ring By-Pass gases mixing with Engine Oil and routes them up and through the Air Box and thence back into the Engine through the gaping mouth of the Intake Manifold.

This process tends to deposit more than a little Engine Oil back into the Top Engine Cylinder Combustion Chambers and with the follow on of incomplete combustion… leaves a very thick, and sticky mess of Carbon Deposits that can collect around the Valve Seats and in and around the Spark Plug Electrodes. GM makes a Top Engine Cleaner that is designed to be burned with a measured quantity of High Octane Fuel… ostensibly to loosen the Carbon inside there and on the Piston Tops and burn/blow this junk out from inside the upper Engine. There are quite a few Threads here at GMTN that instruct on how to do this treatment.

With less than 100 K Miles on your Engine… that is hardly a third of the way through the potential lifespan of your Motor ...so unless the PO badly abused the Engine and Drive Train… you have little to fear at present. For the time being… it might be very helpful to “short-sheet” your Oil Changes to around 2,000 Miles until you can see a drastic improvement in your oil consumption. Avoid Over Filling the Crank Case… as it will do more harm than good. Mobil1 and Only The Best Oil Filters are called for with this Motor... 5W-30 in Summer… 0W-30 in Winter if it gets REAL COLD where you are.

Please remember that “Thoughts… Are Things...” and don’t think for one minute that your SUV does not know and appreciate how you feel about it… so with some “New Owner TLC” ...you’ll be surprised at how well She responds to all of your kind attentions. One last idea is that you will enjoy driving this vehicle more if you can communicate with it via an inexpensive Blue Tooth OBD2 Code Reader and when possible... Take and Post images of anything you can see that looks wrong... is broken ...or you have to re-assemble later and lose your points of reference... and post them with your issues right back here.

Welcome Aboard, Brother!
 
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#3
Sure sounds like he really didn't know or possibly care about this truck since it doesn't have a timing belt but a chain.

Anyway, good suggestions so far to keep monitoring it and checking the oil level often.
 
#4
Sure sounds like he really didn't know or possibly care about this truck since it doesn't have a timing belt but a chain.

Anyway, good suggestions so far to keep monitoring it and checking the oil level often.
Here's the "likely story" I received: Guy bought it for his daughter for her 16th bday. She didn't like it, it was too big. he had to get her a jeep liberty instead. he only had it a couple months. So he had zero knowledge or interest of cars.
So the "timing belt" thing, he could be meant the serp belt. Supposedly this work was done before he bought it. He told me the owner before him picked it up at an auction and did the work. I was skeptical of the auction thing, but someone cared for this truck, it's super clean, had to have been garaged.
he left the registration in the glove box and it's only had a few hundred miles put on it since it was registered.
anyway I guess that's all irrelevant at this point. I will maintain it, I do my own maintenance and repairs.

I appreciate your reply and input.
 
#5
Welcome to GMTN Mr. “E” …

Here are a few suggestions:

To get more familiar with the GMT360 Platform… and the GM Atlas LL8 4.2L Engine in particular… Start at the very top of this section with a fresh cup of coffee and a careful read of the FAQ here:

https://gmtnation.com/forums/threads/faq-vortec-4-2l-i-6.17025

Thank you, I did read the FAQ, excellent info.

Next… follow the instructions provided by @Mooseman ‘s Classic Library of GM OEM Digital Shop Manuals...and download the flavor most suited for your particular vehicle...from here:

https://gmtnation.com/forums/threads/need-service-manuals-get-them-here.361/

I do need to download this, will have to fire up the laptop.

As for the present questions about “Oily Plugs”...The Atlas LL8 Engine has a Positive Crankcase Ventilation System in compliance with EPA requirement to collect Crankcase Oily Vapors that fill the motors interior under the pressure of Piston Ring By-Pass gases mixing with Engine Oil and routes them up and through the Air Box and thence back into the Engine through the gaping mouth of the Intake Manifold.

This process tends to deposit more than a little Engine Oil back into the Top Engine Cylinder Combustion Chambers and with the follow on of incomplete combustion… leaves a very thick, and sticky mess of Carbon Deposits that can collect around the Valve Seats and in and around the Spark Plug Electrodes. GM makes a Top Engine Cleaner that is designed to be burned with a measured quantity of High Octane Fuel… ostensibly to loosen the Carbon inside there and on the Piston Tops and burn/blow this junk out from inside the upper Engine. There are quite a few Threads here at GMTN that instruct on how to do this treatment.

I'll do some searches for this.

With less than 100 K Miles on your Engine… that is hardly a third of the way through the potential lifespan of your Motor ...so unless the PO badly abused the Engine and Drive Train… you have little to fear at present. For the time being… it might be very helpful to “short-sheet” your Oil Changes to around 2,000 Miles until you can see a drastic improvement in your oil consumption. Avoid Over Filling the Crank Case… as it will do more harm than good. Mobil1 and Only The Best Oil Filters are called for with this Motor... 5W-30 in Summer… 0W-30 in Winter if it gets REAL COLD where you are.

I'm a bit nervous about switching to synthetic not knowing what was used in the past? Is that "an old wives tale"?

Please remember that “Thoughts… Are Things...” and don’t think for one minute that your SUV does not know and appreciate how you feel about it… so with some “New Owner TLC” ...you’ll be surprised at how well She responds to all of your kind attentions. One last idea is that you will enjoy driving this vehicle more if you can communicate with it via an inexpensive Blue Tooth OBD2 Code Reader and when possible... Take and Post images of anything you can see that looks wrong... is broken ...or you have to re-assemble later and lose your points of reference... and post them with your issues right back here.

I do have a cheap Amazon code reader but I couldn't get it to read data on the TB. It works on my wife's 00 durango and my moms 05 Saturn. Checked the cigar fuse, 12v on each side. The advance auto parts scanner did connect, no codes.

I'll have to buy a nicer one with live data.

Welcome Aboard, Brother!

Thank you I appreciate your detailed reply. I responded inline.

Here's a couple pics of the plugs. 1 is on the right side of the photos.
 

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#6
Here's an update on the oil consumption:
We have put 350 miles on it since we brought it home, yesterday it was 2 quarts low again.

It's time to plan ahead and figure it'll need a reman engine. I've been reading and watching vids, it's a monumental task I see. I've been maintaining my own vehicles for over 20 years, the only things I have paid for are tires and alignments. Knowing this I'm confident I can handle it.
I really screwed myself on this one. Too late now.
here's a pic of the truck, I rubbed it down with a clay bar this week end. I posted in the appearance category about the rust repair I did on the front of the hood and the rear doors. There clay bar did a nice job of removing overspray (lesson learned, be more thorough with masking).
 

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#7
That is bad luck for that engine at such low mileage since they are not known to be oil burners at all, even at high mileage. Only two ways for oil to migrate into the combustion chamber: rings or valves. A few things you could try. Do a compression test. If the compression is lower on #5 and/or #6, then rings may be affected. Even if the compression is good, maybe they're just stuck. I've heard that ACDelco Top Engine Cleaner can unstick them. I'd fill the cylinders with it (it foams) with 5 & 6 low in the strokes and let it soak several hours. I'd add more every so often when the foam diminishes so it can soak down into the rings. You could also try an engine flush. And after changing the oil, replace two quarts of oil with transmission fluid. In the old days of engines with 5 quarts of oil, you'd replace one quart but with 7 quarts in these engines, you can replace two. The detergents in tranny fluid may also clean up the rings.

If it's the valve seals, there's no way that I can think of to check for that except maybe with a very small boroscope that can be bent 90° at the head to be able to view the open valves and look for oil seeping in. Or see if any oil is landing on the piston tops.

At this point, you have nothing to lose.
 
#8
That is bad luck for that engine at such low mileage since they are not known to be oil burners at all, even at high mileage. Only two ways for oil to migrate into the combustion chamber: rings or valves. A few things you could try. Do a compression test. If the compression is lower on #5 and/or #6, then rings may be affected. Even if the compression is good, maybe they're just stuck. I've heard that ACDelco Top Engine Cleaner can unstick them. I'd fill the cylinders with it (it foams) with 5 & 6 low in the strokes and let it soak several hours. I'd add more every so often when the foam diminishes so it can soak down into the rings. You could also try an engine flush. And after changing the oil, replace two quarts of oil with transmission fluid. In the old days of engines with 5 quarts of oil, you'd replace one quart but with 7 quarts in these engines, you can replace two. The detergents in tranny fluid may also clean up the rings.

If it's the valve seals, there's no way that I can think of to check for that except maybe with a very small boroscope that can be bent 90° at the head to be able to view the open valves and look for oil seeping in. Or see if any oil is landing on the piston tops.

At this point, you have nothing to lose.
thank you very much. I'd like to try the top engine cleaner first. I checked Amazon and there's an aerosol version and a quart can version.

do you know which would be preferable?
 

Redbeard

Well-Known Member
#9
I'd make just one small comment, and don't take it negatively. Make sure you are on level ground and preferable the same spot when you top off the oil level and when you check it later after a couple of miles. It seems when I have checked mine it might seem down a bit but when I back up and look at the ground it isn't perfectly level. When it is check inside my gargage which doesn't have any slope I will get the most accurate reading. It could cost a bit of money and time trying to fix a leak that, maybe, might not be there. The only other simple things to look at is the oil filter and make sure it was secured properly (it doesn't take much to keep it from leaking either) and maybe the oil pressure sensor, but I suspect at 2 qts in 350 miles you would see a nice spot on the floor if is leaking.
 
#11
I'd use the quart can. More concentrated and liquid would seep into the rings easier than the foaming stuff. I can't even get the quarts here which is why I mentioned the spray can. Apparently it's pretty potent stuff. Recommended to me by an old GM mechanic.
 

MRRSM

Lifetime VIP Supporter
#13
Mr. "E"... I know that given the Oil Consumption issue... that it might appear dire at this point... but it is STILL early yet... and unless you have experienced a drastic loss of power ...and your exhaust is blowing plumes of Blue White Smoke in your rear view mirror... please take heart that there may be other things yet to be discovered that will explain the problem in the end... without having to resort to something as drastic as an Engine R&R or Complete Rebuild... just yet. These Atlas Engines have proven to bear up under some incredible abuse...and lived to tell the tale even with mileage approaching 160,000 to 200,000 Miles.

Your Engine would have had to have been wrung out and Beaten like a Bad Tempered Mule in order to be at the point where it needs to just throw in the towel at less than100 K Miles. Something else is at play here... and it just will take a little time to sort these engine problems out. It could be things like a nicked or failed Crankshaft Oil Seal... either on the front or at the back... or both... for example. Examining the under body areas around the motor at the sides of the engine for signs of Oil Drain Down and Dirt-Sludge Collection at leak points will let you see any glaring points of concern.

I'm glad that you are taking the approach to try out the ACDelco Top Engine Cleaner. Among other technological marvels exhibited by this engine are the Very Low Tension experienced by the Two Compression Piston Rings. They are so easily compressible that they WILL very easily stick tight inside the Piston Grooves when the Gas Gum and Carbon Goo conspire to hold them in as the bad stuff bakes in hard and keeps them there. The Judicious use of the ACDelco TEC will definitely show a difference if your compression is low in any or all of those cylinders with the sketchy plugs. I can testify that even after 240,000 Miles prior to my pulling the Engine Head on my 2002 Engine... there was not the slightest indication of any "Ring Ridge" in my First Gen Atlas Motor.

And speaking of those "Baked On Oil Plugs"... That phenomena can be explained by the fact that the OEM "O" Rings located at the inner bottom of the Valve Cover (...NOT the ones around the Top of the Coil On Plugs) will move and rub back and forth enough with hundreds of cooling and heating cycle over time to flatten them completely out and loose their "plump" enough to allow Engine Oil to invade and eventually fill up the deeper well areas around the tightened Spark Plugs... and literally cook the oil to carbon if left in there long enough. It is always wise to cover the opening to those Wells with a rag and use either can of Brake Cleaner, Canned or Compressed Air to blow the oil out from around the deep wells around the Plugs B4 you R&R them... lest too much Engine Oil drip down inside of the engine and you run risk Hydro-locking the engine on start up.

One last suggestion about tackling the job of performing a Complete Engine Rebuild of this GM Atlas LL8 4.2L Motor...

Please... Brother... Don't Do It!

I'm not going to swear that my knowledge of these engines is profound... but I doubt that very many people have spent as much time and money for EVERYTHING that is required to perform this job; You Name it... Parts ...Tools... Gaskets... and the Long Learning Curve here that is more steep than you might want to imagine. There are better Threads to follow for this rebuild for guidance and information than mine... @Mooseman and @mc.millin (The Legendary Mac) should be your first ports of call on such a massive project... but for the complete and finer details on Part Numbers, Photobucket Images of Tear Downs, The New and The Old Components and some Procedures... my two "tomes" and all my Photobucket Links with complete images on this subject can serve later on for other research purposes that you might need to know. If you decide to go crazy and try this on... Along with all the other experienced GMTN Members... I'll do my very best to help you out, as well.
 
#14
@MRRSM thanks for all of the great tips and wit.

I have been going through your threads and photobucket, so nice of you to put all that time in.
Please... Brother... Don't Do It!
This one is the best. Once I saw a reman is $4500 and I saw what was required for yours, that isn't much cheaper.

The tailpipe is sooty, not wet with oil but it doesn't wipe off your finger easily.

no visible smoke, and we have been attuned to it. The only time I saw visible smoke was the day we picked it up, AFTER my wife had the title transferred...of course!

Good tip on the plug wells, I did cover the TB opening and used compressed air in the wells prior to R&R. Strangely they were completely dry and clean, the wells looked like new bare aluminum.

I'm certain the valve cover gasket is new: it's blue, t o me that's FelPro.
The plug wells were completely devoid of oil.

I was told, second hand, that the cylinder head was replaced. I don't see any warranty tags on the visible parts of the head.

There are clues that the engine has been apart: glaringly the fact that the bolt on the rear of the cylinder head that holds the emission hoses (one attaches to the clean air tube to the TB and one attaches to what appears to be an EGR?) is missing.

This, coupled with the fact that the plug wells seem impossibly clean, makes me believe the cylinder head may have indeed been R&R'd.

I researched here and the web in general and found basically nothing on the Atlas engines burning oil and that factored highly in to my confidence in purchasing.

I'm holding out hope that the situation can be improved. I will try the suggestions provided, starting with the TEC.

I was planning to get the engine warm, pull the 2 plugs, disable and bump it over to get the pistons low in the bore, enter the TEC, and let it set overnight. (Mooseman method).
 

MRRSM

Lifetime VIP Supporter
#15
If the suggestion is not coming too late... Before your begin the ACDelco TEC Treatment... Pull the Oil Dip Stick and smell the end of the thing for the presence of Gasoline Odors in the Motor Oil. On Engines bearing MUCH more mileage than yours has,,, that odor would indicate that the Piston Rings vs. Cylinder Walls have worn down to the point of allowing unburned Fuel and Air to bypass them and settle down to destroy the lubricity of the Engine Oil in the Crankcase. If present... then AFTER your TEC Treatment.... Change the Oil and Oil Filter using Mobil1 and your favorite flavor of The Best Oil Filter you can buy... Mobil1, K&N...etc. Also... Central to your knowing WTH is going on inside of this Motor and other BCM issues will be the use of a Decent High End Code Reader... and my considered suggestion is for the purchase of a GM Tech II Clone Kit from AliExpress.com. You will NEVER do better than having that thing as your GM Products Diagnostic Ally:

See Post# 171 for links to the Last, Best Bargain in the "GYMKO" Tech II Kit:

https://gmtnation.com/forums/thread...gm-tech-ii-scan-tool.17878/page-5#post-556080
 
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#16
Not too late, the TEC has not arrived yet, hoping for the weekend.

I smelled the oil last night and I didn't notice a gasoline scent. However I will check again prior now that I have read your advice.

I planned on an oil change/flush with ATF (per Moosemans suggestion) after the TEC treatment, and then on to synthetic/best filter possible per your advice.

My wife had it stall on her yesterday so she took it home and drove something else.

After work I took it out and hammered it a couple times. It's sluggish until it hits about 4k rpm, then it puffs a huge cloud of black & blue smoke (looking in the rearview mirror) and then kicks in like it has a turbo.

As for the code scanner: thank you for the link! I have a $15 Amazon reader and it won't even read from the TH for some reason. It lights up and tries, but shows link error.Junk I guess. It does read on my wife's durango and my moms saturn.

I'm going to hold off on the scan tool for now. If I can't recover this engine, you have already advised to not attempt the r&r.
my only recourse will be to sell the truck for a huge loss and big lesson learned.

not giving up, just planning ahead.
 

MRRSM

Lifetime VIP Supporter
#17
Okeedoke... You seem to possess an organized mind and a willingness to be methodical in your approach to sorting these issue(s) out... THAT is half the Battle WON, right there! Now if only "The Lil Woman" will be as patient... :>)