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.
 
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EPfiffner

Active Member
#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.
 
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EPfiffner

Active Member
#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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EPfiffner

Active Member
#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.
 
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EPfiffner

Active Member
#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.
 
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EPfiffner

Active Member
#12
Thanks again. it's on order. You know it's potent stuff when it comes in a metal can! lol

hopefully it's here by the weekend.

I'll do the engine flush at some point also.

I'll post back with how it goes.
 

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 @m.mcmillen (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 one... Along with all the other experienced GMTN Members, I'll do my very best to help you out, as well.
 
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EPfiffner

Active Member
#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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EPfiffner

Active Member
#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... :>)
 
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EPfiffner

Active Member
#18
Got the "juice" yesterday! And no, I'm not grilling hot dogs in the garage, I had the wife pick those up as a possible way to inject the TEC in to the plug holes. I use one for lacquer thinner to clean my spray gun, and it works great for that.

oh and here's a pic of my MGB that I'm restoring. Off topic, but I figured a quick pic wouldn't hurt.
 

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MRRSM

Lifetime VIP Supporter
#20
You could use a clear vinyl tube to snake down past the Spark Plug Holes and deliver the stuff that way... Just know that this noxious chemical will remain in a Black Soupy condition overnight ...if not longer... as it will gradually dissolve the Carbon Deposits on the Piston Tops as well. When you are satisfied that the Piston Rings have had a good soaking... place some Blue Shop Towels wadded up inside and just above each open Spark Plug Hole. Then pull the Fuel Pump Relay to avoid having the EFIs spraying Fuel into the Cylinders 'watering down' the TEC...and bump the Starter to turn the Engine over long enough to allow the TEC the chance to pressurize in all six cylinders and then exit as a spray through the open Spark Plug Holes.

Doing this will prevent the Engine from Hydro-Locking and bending the Con-Rods by prematurely installing the Spark Plugs. Wear some Eye Protection and Nitrile Gloves and keep a large Zip-Lock Baggy handy to place those six, noxious Blue Shop Rags inside after you wipe out and sop up all that Black Goo that will spray out when the Engine is rotating. Re-install the Fuel Pump Relay afterwards and after installing your New Spark Plugs... spray out those wells again with some Brake Cleaner (The TEC WILL dissolve the Glue holding the COP Grommets around their seal levels if that stuff is left in there), and then Canned or Compressed Air prior to installing the Coil On Plugs and then 'gingerly' tightening down their center bolts.
 
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EPfiffner

Active Member
#21
Hope the TEC doesn't eat through those bottles!
I was actually disappointed the stuff didn't smell any more ripe than it does, lol

Smells like fish and rubbing alcohol to me.

I'll test, but lacquer thinner doesn't melt 'em.

You could use a clear vinyl tube to snake down past the Spark Plug Holes and deliver the stuff that way... Just know that this noxious chemical will remain in a Black Soupy condition overnight ...if not longer... as it will gradually dissolve the Carbon Deposits on the Piston Tops as well. When you are satisfied that the Piston Rings have had a good soaking... place some Blue Shop Towels wadded up inside and just above each open Spark Plug Hole. Then pull the Fuel Pump Relay to avoid having the EFIs spraying Fuel into the Cylinders 'watering down' the TEC...and bump the Starter to turn the Engine over long enough to allow the TEC the chance to pressurize in all six cylinders and then exit as a spray through the open Spark Plug Holes.

Doing this will prevent the Engine from Hydro-Locking and bending the Con-Rods by prematurely installing the Spark Plugs. Wear some Eye Protection and Nitrile Gloves and keep a large Zip-Lock Baggy handy to place those six, noxious Blue Shop Rags inside after you wipe out and sop up all that Black Goo that will spray out when the Engine is rotating. Re-install the Fuel Pump Relay afterwards and after installing your New Spark Plugs... spray out those wells again with some Brake Cleaner (The TEC WILL dissolve the Glue holding the COP Grommets around their seal levels if that stuff is left in there), and then Canned or Compressed Air prior to installing the Coil On Plugs and then 'gingerly' tightening down their center bolts.
Thanks @MRRSM. I have the PPE so will do.

I was thinking of some tubing on the end of the squeeze bottle so good call.

I'm going to start the soak this eve on a warm engine.

I will definitely disable it with the FP relay, crank it over to prevent hydrolock, and clean well before reassemby.
 
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EPfiffner

Active Member
#22
Here's a rundown on the de-carboning repair attempt, I tried to follow/consider everyone's advice:

-Go for a drive Friday eve to warm up the engine.
-pull #5 and #6 plugs with warm engine. I was surprised to see that the plugs looked to be firing well.

-Pull FP relay, crank engine to run out of fuel.
-check that pistons were part way down the bore.
-fill both cylinders with TEC. Ketchup bottle and vacuum hose worked well. I split the entire quart between the 2 suspect cylinders. Screw plugs back in a couple threads.

-Check in the morning. I was shocked to see that #5 had held the liquid all night! #6 had leaked through.
-Suction out remaining TEC. Drain oil, change w/ 5qts Dino and 2 qts ATF, delco PF61.
-Stuff rags in plug wells, crank engine to evacuate.
-inspect piston tops w/mirror and flashlight. I could now see clean aluminum.
-reinstall same plugs, clean plug wells w/ carb cleaner and compressed air.
-fire up and drive approx 15 mi on highway in 3rd gear.

-Pull plugs in warm engine, soak piston tops in PB blaster. Crank over, add more PB.
-reinstall same plugs, take for short drive.
-change oil and filter to 7qts M1 high mileage and M1 filter.

We shall see...I reset the OCM and Trip B so I could monitor. I also paid special attention to the oil level on the stick when freshly filled w/7 qts.

One thing I am curious about after reading some of @MRRSM's posts: this pic does not show it well, but I wonder if when the VC gasket was replaced if the plug well seals where either a) installed incorrectly or b) knocked out of groove?

The threads on the plugs always seem oily, but the wells are not full of oil. I can't imagine the oil working it's way through the plug seat, all of the threads, and in to the combustion chamber?

I cleaned the wells scrupulously, and I'll check the plugs after a few hundred miles of so.

thanks again to everyone for the tips and advice.
 

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m.mcmillen

Gold Supporter
#23

MRRSM

Lifetime VIP Supporter
#24
Mr. "E" ... re: Post #22

You are entirely correct about the issue of having the "replaced" eccentric individual Valve Cover Spark Plug Hole Gaskets ..."misplaced"... as when installing them... while all of the mating contact upper (or lower...depending upon your perspective) surfaces that meet the Aluminum Engine Head... are ROUND... their insert point edges that plug into the composite black Valve Cover Grooves are designed with inverted "T" shaped ledges that require MUCH more effort to ensure that they all are indeed seated deep and completely inside the cover. And merely 'pushing them in' to accomplish this PITA task in a casual manner... will prove to be insufficient. In my own experience... you really have to work at getting them all carefully and completely fitted inside of their proper places and it requires no small amount of attention to ensure that this will be so. How something so important can often be approached as triviality is a puzzle... considering what needs to be done to keep the Oil inside the Motor...and the damaging Dirt, Debris and Water...out.

Otherwise.. .as the various Aluminum Head components begin to heat up to expand and cool down to contract... in very short order... they will tend to come right back out... tilting and failing ...even as the Valve Cover Captured Fasteners are being snugged in place. And with those Spark Plug Seals in particular, you would have no way of knowing... whether Old ...or New... if they are properly "in the grooves"... or not. Based upon the "Missing Fastener" at the back of the head as you previously mentioned strongly indicating the Head was previously R&Red... other people's mechanical repairs can often be quite specious at best. So it may in the end require the removal and inspection of the whole cover to investigate this perpetual Oil Leak Problem... or else it will remain being a "Pebble in Your Shoe".
 
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NJTB

Well-Known Member
#25
GM top engine cleaner was the go to fix for carbon knocks in the late 80's.
Came in pint cans, you'd warm the car up, pour about half of it slowly into the air intake while revving the engine, then the rest quickly until the engine stalled. Start the car up and drive it. You wouldn't believe the smoke that came out, worse than any head gasket you ever saw.
Never had one come back for the same problem.
 
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EPfiffner

Active Member
#26
If you don't need to replace the sleeves, it isn't that expensive. I had about $2,000 in mine and that includes having the head rebuilt and the cylinders honed.

Here is the link to my thread that shows my rebuild https://gmtnation.com/forums/threads/4-2-engine-rebuild.16080/
thank you for the link! Excellent info, very concise. I would be OK with the rebuild, it may be less for me if the head has already R&R'ed although I would have the shop go through it.

Mr. "E" ... re: Post #22

You are entirely correct about the issue of having the "replaced" eccentric individual Valve Cover Spark Plug Hole Gaskets ..."misplaced"... as when installing them... while all of the mating contact upper (or lower...depending upon your perspective) surfaces that meet the Aluminum Engine Head... are ROUND... their insert point edges that plug into the composite black Valve Cover Grooves are designed with inverted "T" shaped ledges that require MUCH more effort to ensure that they all are indeed seated deep and completely inside the cover. And merely 'pushing them in' to accomplish this PITA task in a casual manner... will prove to be insufficient. In my own experience... you really have to work at getting them all carefully and completely fitted inside of their proper places and it requires no small amount of attention to ensure that this will be so. How something so important can often be approached as triviality is a puzzle... considering what needs to be done to keep the Oil inside the Motor...and the damaging Dirt, Debris and Water...out.

Otherwise.. .as the various Aluminum Head components begin to heat up to expand and cool down to contract... in very short order... they will tend to come right back out... tilting and failing ...even as the Valve Cover Captured Fasteners are being snugged in place. And with those Spark Plug Seals in particular, you would have no way of knowing... whether Old ...or New... if they are properly "in the grooves"... or not. Based upon the "Missing Fastener" at the back of the head as you previously mentioned strongly indicating the Head was previously R&Red... other people's mechanical repairs can often be quite specious at best. So it may in the end require the removal and inspection of the whole cover to investigate this perpetual Oil Leak Problem... or else it will remain being a "Pebble in Your Shoe".
I actually learned about the spark plug hole gaskets from one of your threads @MRRSM. Once my wife puts some more miles on it I am going to take out the COP and check, I had the aluminum completely devoid of oil when I reassembled so I should be able to tell if it's coming in.
however I can't imagine the oil leaking all the way down in to the combustion chamber to be burned. If the tapered seat at the head/plug seals combustion pressure I can't imagine oil getting through.

GM top engine cleaner was the go to fix for carbon knocks in the late 80's.
Came in pint cans, you'd warm the car up, pour about half of it slowly into the air intake while revving the engine, then the rest quickly until the engine stalled. Start the car up and drive it. You wouldn't believe the smoke that came out, worse than any head gasket you ever saw.
Never had one come back for the same problem.
This was a quart can, and my method of usage is definitely unorthodox, but as @Mooseman said, I have nothing to lose at this point.
great to hear success stories of the product, we shall see.
 
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EPfiffner

Active Member
#27
Good morning, I hope everyone has a great holiday weekend.

Here's a 326 mile update: added one quart (it was down about halfway in to the crosshatch on the dipstick).

I pulled plugs #5 and #6, photos attached. I learned that there is definitely not oil leaking at the VC gasket/spark plug wells, they were completely dry.

I'm still in denial on this, and continuing my "snake oil" kick. I bought some Kano Kroil penetrant and did a hot engine piston soak with that.

So consumption has definitely diminished, but it's still pretty bad.
 

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EPfiffner

Active Member
#28
711 miles, added another quart so we are at 1qt every 350 miles.
This weekend I was riding in the passenger seat when it did the "stalling" that my wife had explained.

It was much more than just stalling, it was like it went in to limp mode. It would not accelerate, period. It happens when the engine is cold.

To me it felt like when fuel pressure is low. She just calmly turned on the 4 way flashers and coaxed it along, and after a minute or so it drove as "normal", whatever normal is for this thing.

I also noticed, since the exhaust is below the passenger seat, that it sounds like it is misfiring, right in the midrange rpms where I have felt like it's low on power. Could be the cat plugged from the oil burning.

Also, I got a bluetooth adapter and torque pro, I love it! Still trying to learn how to use it, but I got the extended gm stuff loaded, and figured out how to record.

So this weekend is compression test just to verify that she's toast. If cylinders are low then there's my problem. If not I will investigate fuel pressure and back pressure.
 

MRRSM

Lifetime VIP Supporter
#29
I've been thinking about the question of where so much Motor Oil would go during such a short driving distance ...and I realized that sometimes I have to remind myself that the Throttle Body and Intake Manifold on this unique engine don't behave like a typical Throttle Body Injection System... and that with the possible exception of the Piston-Ring Blow-By Engine Vapors making their way up into the Air Box and thence through the Throttle Body Opening for Re-Cycling purposes... the only stuff that should be passing through that circuit...starting with the Air Filter Box... is AIR.

But you never realize just how much Motor Oil CAN be re-directed through these components... until you remove the TB/Intake Manifold and can observe just how much Oily Black Crud has been building and collecting over time inside of the Intake Ports on the Engine Head... suggesting that a terrible excess of Motor Oil is being constantly ingested in this manner. There have been reports of the Motor Oil actually cooling down and condensing at such a high rate as to form a large pool of liquid Motor Oil settled down inside the bottom of the Air Box... well past the limb-edge of where the short rubber hose connecting the Air Box to the Valve Cover is situated.

Now you might look at these images of my 2004 GM Atlas LL8 4.2L Engine with 160,000 Miles of wear and tear on it where I took some close-up images of these exact positions on the Intake side of the Stand Mounted Engine and think... "Well Bobby... THAT stuff is just the Dirt that passed by your Air Filter because it was too dirty... or perhaps the IM was just loose."


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But if you look at the contrast between these two attached images... you'll see a clean streak on there that I swiped off as soon as I unbolted and removed the IM... and found that this stuff was recently deposited, fresh... and easily removed with a cloth wipe. Some of the Intake Ports actually had relatively Fresh, Almond colored Motor Oil... literally ... dripping out.

So there MUST be something going on here that is forcing the Oil and Oil Vapors up through the two rubber tubes that feed the Crankcase Oil/Vapors up and into the Air Stream: either from the connecting Rubber Tube fixed on the Lower Center of the Intake Manifold and a Port in the IM side of the Engine Head... or via the Rubber Tube situated between the Valve Cover and the Air Box attached to the Throttle Body. Is the Drain Back Oil from the top of the Valve Train somehow getting sucked back up into the IM via that lower IM tube? Its too bad that there is not a convenient Oil Catch Can to intercede and allow the means for finding out if this is what is making so much Motor Oil ...disappear.

If present... The CAT Back Pressure might be playing a role in this, too... so your Back Pressure Test results will prove very interesting. And one of the reasons why the CAT might be so clogged up as to reduce Volumetric Efficiency and restrict the exiting exhaust stream...is because it probably has been working overtime in order to try and burn up all of that Oily Exhaust that hits those 900 Degree Fahrenheit Honeycombs and get burned up on its way out the Tail Pipe. These next images are from my 2002 GM LL8 4.2L Engine ...and you can see from the amount of Carbon Build that happened after 240,000 Miles that something 'other than Mid Grade Gasoline' has left an awful lot of residue on those Piston Tops. This Carbon Mass increases compression by reducing Quench... and it can cause pre-ignition and misfires, too when those Carbon Flakes start to "glow":

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EPfiffner

Active Member
#30
I've been thinking about the question of where so much Motor Oil would go during such a short driving distance ...and I realized that sometimes I have to remind myself that the Throttle Body and Intake Manifold on this unique engine don't behave like a typical Throttle Body Injection System... and that with the possible exception of the Piston-Ring Blow-By Engine Vapors making their way up into the Air Box and thence through the Throttle Body Opening for Re-Cycling purposes... the only stuff that should be passing through that circuit...starting with the Air Filter Box... is AIR.

But you never realize just how much Motor Oil CAN be re-directed through these components... until you remove the TB/Intake Manifold and can observe just how much Oily Black Crud has been building and collecting over time inside of the Intake Ports on the Engine Head... suggesting that a terrible excess of Motor Oil is being constantly ingested in this manner. There have been reports of the Motor Oil actually cooling down and condensing at such a high rate as to form a large pool of liquid Motor Oil settled down inside the bottom of the Air Box... well past the limb-edge of where the short rubber hose connecting the Air Box to the Valve Cover is situated.

Now you might look at these images of my 2004 GM Atlas LL8 4.2L Engine with 160,000 Miles of wear and tear on it where I took some close-up images of these exact positions on the Intake side of the Stand Mounted Engine and think... "Well Bobby... THAT stuff is just the Dirt that passed by your Air Filter because it was too dirty... or perhaps the IM was just loose."

View attachment 85305

View attachment 85306

But if you look at the contrast between these two attached images... you'll see a clean streak on there that I swiped off as soon as I unbolted and removed the IM... and found that this stuff was recently deposited, fresh... and easily removed with a cloth wipe. Some of the Intake Ports actually had reI'mlatively Fresh, Almond colored Motor Oil... literally ... dripping out.

So there MUST be something going on here that is forcing the Oil and Oil Vapors up through the two rubber tubes that feed the Crankcase Oil/Vapors up and into the Air Stream: either from the connecting Rubber Tube fixed on the Lower Center of the Intake Manifold and a Port in the IM side of the Engine Head... or via the Rubber Tube situated between the Valve Cover and the Air Box attached to the Throttle Body. Is the Drain Back Oil from the top of the Valve Train somehow getting sucked back up into the IM via that lower IM tube? Its too bad that there is not a convenient Oil Catch Can to intercede and allow the means for finding out if this is what is making so much Motor Oil ...disappear.

If present... The CAT Back Pressure might be playing a role in this, too... so your Back Pressure Test results will prove very interesting. And one of the reasons why the CAT might be so clogged up as to reduce Volumetric Efficiency and restrict the exiting exhaust stream...is because it probably has been working overtime in order to try and burn up all of that Oily Exhaust that hits those 900 Degree Fahrenheit Honeycombs and get burned up on its way out the Tail Pipe. These next images are from my 2002 GM LL8 4.2L Engine ...and you can see from the amount of Carbon Build that happened after 240,000 Miles that something 'other than Mid Grade Gasoline' has left an awful lot of residue on those Piston Tops. This Carbon Mass increases compression by reducing Quench... and it can cause pre-ignition and misfires, too when those Carbon Flakes start to "glow":

View attachment 85308

View attachment 85309

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View attachment 85312

Thanks for the reply. It is astounding that so much Mobil1 can disappear.
It's parked in the same spot on a level cement driveway every day so unless I am physically blinded by denial, it has to be ingesting it.

I agree with everything you have written about the crankcase ventilation, so a month ago when I had the TB off I was blown away that there were no signs of oil Anywhere in the resonator box. With the TB off you can get a view in to the intake, and also no sign of oil!

I have yet to investigate the hose you mentioned that attaches to the lower IM. I think I will start the truck with the elbow that runs between the resonator and the VC disconnected and see if there's vacuum.

Unfortunately there's not much point investigating our crankcase ventilation theories with the engine in situ since all signs are pointing to a repair that cannot be completed without R&R.
 
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EPfiffner

Active Member
#31
Good morning GMTNation!
I completed some testing this weekend, I'll try to keep it short n sweet:

Dry compression:
#1: 185psi
#2: 195psi
#3: 185psi
#4: 185psi
#5: 185psi
#6: 185psi

Leakdown, w/ my dad's homemade rig. 32psi regulated applied to cylinder then shut off air supply, count how many seconds to bleed off:

#1: 2s (bleeds through VC breather nipple)
#2: 6s
#3: 5s
#4: 3s (bleeds through VC breather nipple)
#5: 6s
#6: 5s

Fuel pressure: KOEO: 62psi, drops to 58psi when pump prime is over
Idle: 58psi
Driving: holds around 58-62psi

I rented the FP gauge kit from AZ. It has a bleed hose on it so I was curious what would happen if I held in the bleed while the truck was running. To my surprise barely any fuel trickled out and the pressure dropped to between 30-40psi. Not sure if this is normal (This test was more for the driveability issue, not the oil consumption).

I could not find a back pressure tester for rent. I tested the cat temps inlet and outlet with my laser temp gauge.
Inlet: 260 F
Outlet: 530 F

I went over all of this with my dad and his theory is it might be worth retrofitting a PCV or a catch can, and this goes right along with @MRRSM 's pics and suggestions of how the oil gets pulled in via vacuum and pools in the bottom of the intake runners.
 

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MRRSM

Lifetime VIP Supporter
#32
If you both manage to come up with a Practical Design for your idea... Please do a Write Up with the same fastidious attention to the details and procedures you have demonstrated on this repair issue in Digital Images. We would all be very grateful to share in your Invention!

About the Air Pressure Bleeding through into the PVC Nipple of the Valve Cover... WOW... This is NEW... And WTF ?(I mean of course...Where TF?) is THAT pressure coming from? I put my Thinking Cap on about this problem and now I'm guessing that the Real Problem is Bad Valve Guide Seals ... because THAT would be a regular source of more than enough constant pressure escaping from each Cylinder to drive Liquid Oil and Vapors right back up through that vertical tube and into the Air Box.

So between the PUSH of Pressure coming from inside of the Valve Cover ...and the PULL of Suction coming from inside of the Intake Manifold Vacuum... these two recombinant forces are taking a LOT of the Liquid Oil and Oily Vapors upwards and into the Air Box with enough force to drag the oil through that Nipple Tube...and Rob the Returning Mobil1 Motor Oil of the Chance to do so....without a doubt!

I would be very curious to know what the PSI Level is of the Escaping Air pushing through that Nipple is. It make me wonder if by opening up the diameter of that Plastic Nipple end... the Venturi Effect might be DIMINISHED and RELIEVED. Right now...the condition is probably helping to increase the Air Velocity (and thereby Lowering Air Pressure even MORE courtesy "Bernoulli's Principle") to cause a serious increase in the Suction Pull upwards on the Liquid Motor Oil and Vapors . Also... If that vertical Plastic/Nipple Tube was also Clogged... its reduced inner diameter could serve to increase that Venturi-Like Effect as well!

Congratulations... THIS... Is a Good Investigation!

To see How this principle works ...without the Long Science Read... Just Watch the Demo Video at Mid-Page
https://en.wikipedia.org/wiki/Bernoulli's_principle
 
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m.mcmillen

Gold Supporter
#33
I put my Thinking Cap on about this problem and now I'm guessing that the Real Problem is Bad Valve Guide Seals ... because THAT would be a regular source of more than enough constant pressure escaping from each Cylinder to drive Liquid Oil and Vapors right back up through that vertical tube and into the Air Box.
I don't think that valve guide seals would leak when doing a leak down test because the valves are closed. The air has no way to get to the valve guide seals unless there is a burned valve which I don't think is the case judging by the compression readings.
 

MRRSM

Lifetime VIP Supporter
#34
Damn... Absolutely Right... even though the escaping Exhaust is in a Pressurized Atmospheric State that is exposed to the Valve Stems in the Exhaust Ports via the exhaust stream. So the Mystery of the Incoming Air Pressure continues... Perhaps by checking the amount of Air Pressure escaping from under the Valve Cover via the PCV Tube-Nipple... with the Engine Running would provide more clues if it changes with increases in RPM from Idle on upwards?
 
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m.mcmillen

Gold Supporter
#35
I think the only other thing it could be is rings. A lot of shops now favor a leak down test over a compression test because the compression test can be somewhat deceiving. If it was worn valves I would say that the compression would definitely be low.
 

MRRSM

Lifetime VIP Supporter
#36
Damn... I just realized the one other source for Air Pressure is the fact the those " rhomboid shaped" Oil Drain Down Channels built into both sides of the Engine Block leading from the edges of the Upper Engine Head ...allow immediate access to the Lower Engine Case Blow-By gasses. Those pressurized vapors can access the interior of the space under the Valve Cover...bearing out your thinking that Bad Rings with Increased Internal Pressure WOULD be the source of the added pressure. Brother... I think YOU have nailed it!
 
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EPfiffner

Active Member
#37
Thanks guys. As soon as I told my dad it was coming from the VC breather he said "yep, blowby".
I've got to decide what to do now. Dad suggested the PCV retrofit or oil catch can. I found some posts where air compressor line water separators have been made in to oil catch cans.
I may try it, but with that much consumption it can't be long for this world.

Now I'm gonna be 100% honest. I'm in to this thing $6500. It has a lien on it. I paid way high on it because it was low miles and in excellent condition (other than all this) lol
I could blow my entire life savings and pay it off to get the title, and then trade it for a huge loss. That's wrong, but..

Or I could put several $k and 6months of nights and weekends in to it and fix 'er up! "The mighty mac" @m.mcmillen did it!

Sorry sorry, just thinking out loud..
 

MRRSM

Lifetime VIP Supporter
#38
You have already demonstrated that you have enough skill, intuition and desire to take on this project… so you will not get any more discouraging words from me. I like the idea of using the precise (and concise) guidance offered by “The Legendary Mac” as your Compass, Sextant and Binnacle for this Project. I would steer you away from my own threads (Tomes… more the like) ...with the possible exception of suggesting that you will not find a more complete list of the Parts, Pieces and Part Numbers and their images anywhere else for the Atlas Engine… and thankfully that information is on either the First and/or Second pages of this link below.

https://gmtnation.com/forums/threads/the-85-000-00-gm-4-2l-engine-repair.14423/

If you get into the weeds about Block Prep, Broken Crankshaft Bolt R&Rs or if it comes down to having to replace all or some of the Cylinder Sleeves inside of the engine block ...my other more contemporary Thread on the Complete Rebuild of a 2004 GM Atlas LL8 has a lot of information and links to images that can be found here:

https://gmtnation.com/forums/thread...-gm-atlas-4-2l-motor.15786/page-4#post-558441

… and because my Photobucket links are now FUBARed…. I created a New Flickr Account that will have the related images of Disassembly and Tools, Parts and Part Numbers as well and you can visit here to find those readily available for Download as well. God Knows… you will be entering the realm of the GM Atlas LL8 Engine Rebuild ...Where the Air is Thin and Hard to Breath at first… but it will get easier over time as you make progress. Besides… With your Father there to act as Your Good Right Arm… you could not be in a better position for success. I can also help and advise you about this bizarre and amazing Engine ...if needed.

https://www.flickr.com/photos/126111508@N07/albums

About The Money for New Parts…

You can save yourself a lot of Bread ...especially where it concerns costly fasteners for the Motor by searching via Google and eBay for the Part Numbers...and avoid the trap of sticking too closely to insisting that those GM OEM Fastener Parts be EXCLUSIVELY for the GM Atlas 4.2L LL8 Engine. You will be surprised to discover that the GM Engineers cross-pollinate their various Engine Platforms with using the SAME FASTENERS ...regardless of Engine Displacement, etc...as long as they share the Same OEM Part Numbers and Metric Dimensions. There are a LOT of them holding this Motor together that are TTY (Torque To Yield) that will cost a small fortune... so if you can find them in small lots here and there … you’ll be able to build up a decent stock well in advance of putting the Engine Block back together and having to eat large outlays on such expenses.
 
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BRomanJr

Well-Known Member
#39
I've been following this thread and was under the impression that you only cleaned the Rings on Cyl 5 and 6, if so then it's probably time to do Cyl 1 and 4. and why not 2 and 3 to finish it off.
 
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EPfiffner

Active Member
#40
I've been following this thread and was under the impression that you only cleaned the Rings on Cyl 5 and 6, if so then it's probably time to do Cyl 1 and 4. and why not 2 and 3 to finish it off.
Good point. I failed to mention in my previous post from this weekend's testing that after I discovered the leakdown on #1 & #4, I soaked #1-#4 in kroil, bumped it over with the starter , and soaked them again prior to reassembly.

I couldn't follow my original process because I was out of TEC and the engine was cold, but re-treating #1-#4 is a breeze compared to the back 2!
 

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