NEED HELP Vortec 4.2L I-6 2006 Trailblazer 2 Wheel Drive Oil Pan Removal

wes112565

Original poster
Member
Oct 4, 2013
13
Hello all,,

First post on here.
I am in the need of a manual (step by step) on pulling the oil pan with engine still in frame.
I have read many threads of folks having same issue of the oil gauge falling to 0.
I have replaced oil pressure sensors, no fix.
I have dealt with this awhile, first drained oil and to my surprise it was like something you would find in the bottom of a marsh, this 3 weeks after i just had it serviced at a local oil change shop.
That's another story for another time

Any ways after 5 oil changes and filters with in 6 weeks, I continue to have the oil pressure drop to Zero, I know its not just gauges if you leave it running for a period of time the lifter will start to sing to you. I actually cut some of the filters open to find a lot of residue crud in them.
Every time I drain oil I get a lot of fine fine residue, kind like a varnish look.

So my next step I assume will be to drop pan and clean lower engine out and service the oil pick up screen,
I believe i am getting a plugged off screen issue.

When it does this you can set for around 5 minutes and start it up and 40lbs on the oil gauge but you drive it for a-bit and you can see the gauge just gradually drop to 0.


Any help would be appreciated greatly,
Thank you Wes
 

Mooseman

Moderator
Dec 4, 2011
25,262
Ottawa, ON
Do not even bother looking at the oil pressure gauge. It's fake, period. The sensor is just an on/off switch. You need to hook up a mechanical test gauge to see the real pressures. It could be pickup blockage, a leaking pickup seal at the pump or the pump/pressure relief valve.

What do you.mean that the oil was like it was from a marsh? If it is milky, you have more issues with coolant in the oil. And the metal bits you're finding aren't good neither. Please be more precise about what you're finding.
 

wes112565

Original poster
Member
Oct 4, 2013
13
Mooseman; Thank you for reply

What i meant by "you would find in the bottom of a marsh"
the oil was thick and had clumps in it as if it had not been changed in a long time.
But this vehicle had always been taking to a oil service shop from being bought new, and to find this when i pulled the drain plug was unexpected.
No evidence of moister / water in the oil.
No metal fragments evidance either, motor runs great just the issue of loss oil pressure.

The pickup blockage you mentioned, oil sump screen is what i believe the problem is. I will look at the links in your reply for a manual to do the pan removal in the frame.

Thank you kindly.
 

MaddmannDA

Member
Apr 18, 2012
9
Hello all,,

First post on here.
I am in the need of a manual (step by step) on pulling the oil pan with engine still in frame.
I have read many threads of folks having same issue of the oil gauge falling to 0.
I have replaced oil pressure sensors, no fix.
I have dealt with this awhile, first drained oil and to my surprise it was like something you would find in the bottom of a marsh, this 3 weeks after i just had it serviced at a local oil change shop.
That's another story for another time

Any ways after 5 oil changes and filters with in 6 weeks, I continue to have the oil pressure drop to Zero, I know its not just gauges if you leave it running for a period of time the lifter will start to sing to you. I actually cut some of the filters open to find a lot of residue crud in them.
Every time I drain oil I get a lot of fine fine residue, kind like a varnish look.

So my next step I assume will be to drop pan and clean lower engine out and service the oil pick up screen,
I believe i am getting a plugged off screen issue.

When it does this you can set for around 5 minutes and start it up and 40lbs on the oil gauge but you drive it for a-bit and you can see the gauge just gradually drop to 0.


Any help would be appreciated greatly,
Thank you Wes

I have a Turbo Shelby CSX that had the same muck in the bottom of the pan...looked like gravy that coagulated in the fridge. It wasn't milky like water/oil mix I've seen...I purchased the car with most of engine apart so I don't know history, but rest of engine looks great...no ridge or marks on cylinder wall, etc.
I am also curious what could cause that...maybe an additive?
 
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Mooseman

Moderator
Dec 4, 2011
25,262
Ottawa, ON
Pan removal is no trivial thing although the lack of 4x4 components makes it easier somewhat.
How to remove I6 oil pan in vehicle

Before doing that, I'd do an oil change and run some flush. Another oil change and check the real oil pressure.
 
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wes112565

Original poster
Member
Oct 4, 2013
13
Mooseman; Thank you for the information
Here is an update with pics if it will allow me to share them.

Followed the directions to T, after getting it jacked up and on stands it took me about 1.5 hours to have the pan on the ground.

Found exactly what I expected to find, oil Sump screen 3/4 blocked off.
The pan has about a 1/4" of stuck together sludge, still there even from the previous attempts of cleaning it out with a cleaning solution and air sprayer to wash it out through the drain plug. Again thank you very much for your assistance it is greatly appreciated.


Wes1.jpg 2pan.jpg 3block.jpg 5.jpg .
Going to have to wash every thing on the lower end now I can see it..
Just hope upper side doesn't have such a surprise for me in the future.
 

wes112565

Original poster
Member
Oct 4, 2013
13
I have a Turbo Shelby CSX that had the same muck in the bottom of the pan...looked like gravy that coagulated in the fridge. It wasn't milky like water/oil mix I've seen...I purchased the car with most of engine apart so I don't know history, but rest of engine looks great...no ridge or marks on cylinder wall, etc.
I am also curious what could cause that...maybe an additive?

In my situation this was lack of actually changing the oil, but instead screwing on a new filter and saying it was good to go.

This is the only reason I see that my engine was in the condition it was in after getting oil pan dropped off.

This is my wife's vehicle and she took to local quick oil change shop for the life of the vehicle it has around 82000 miles on it and she was stickler on getting it serviced, by all rights it should not be in this condition.
 

mrrsm

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The Most Reliable Solvent you can use...is to spray down one, small section at a time with THIS Stuff.... GM Top Engine Cleaner:

Look here at Post #75 and #76 to see what this stuff does... "The Before vs. The After":

http://gmtnation.com/forums/threads...-gm-atlas-4-2l-motor.15786/page-2#post-523873
71WnQvYaOAL._SL1500_.jpg

This Stuff will De-Varnish and De-Carbonize those areas...as long as you don't overdo it and keep a Drip Pan, Full Face Shield and a Fan moving Fresh Air around you so you don't suffocate from the Fumes... Don't attempt this in a Closed Garage. This stuff is miraculous... and nothing else even comes close to 2nd Place. It will take 3-4 Cans to do the entire Bottom End, the Front of the engine under the Front Cover and the Engine Head.... and SPRAY THE HELL OUT OF THE OIL PAN AND WATCH THAT BLACK "MUNG" DISSOLVE AWAY!

Then you must do at LEAST two Oil and Oil Filter Changes with inexpensive oil to flush out this stuff. You should consider doing an Engine Oil Flush (One Quart of Flush with the Oil... run the engine for ONLY FIVE MINUTES WHILE IDLING... THEN DRAIN THE OIL AND CHANGE THE OUT THE OIL AND OIL FILTER TO THE 2nd BATCH OF INEXPENSIVE OIL.. THEN CHANGE THAT OIL AND OIL FILTER AFTER ONE WEEK... And Last But Not Least:

Use Mobil1 and Mobil1 Oil Filters...
Change BOTH Every 1,500 Miles Xs 2
After THAT Then... Change BOTH Every 3,000 Miles... Forever...

https://www.amazon.com/Genuine-1052626-Engine-Injector-Cleaner/dp/B000QII698?SubscriptionId=AKIAILSHYYTFIVPWUY6Q&tag=duckduckgo-d-20&linkCode=xm2&camp=2025&creative=165953&creativeASIN=B000QII698
 
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wes112565

Original poster
Member
Oct 4, 2013
13
Wow thanks MRRSM,
I will definitely look into getting some of this to cleaner up, was thinking like berrymans but this looks as if it will do the job.

Thanks Wes
 

Mooseman

Moderator
Dec 4, 2011
25,262
Ottawa, ON
And don't forget to clean the CPAS as it's probably as plugged up as the pickup. I'd also run flush with the new oil (after confirming good oil pressure), drain and refill with a good quality synth oil and filter.
 

djthumper

Administrator
Nov 20, 2011
14,950
North Las Vegas
Once you are done with the cleaning and the flush, let me know if you want oil... I am the local AMSOIL Dealer on the Forum.

Steve
Did not realize that we had a preferred deal that the site used...
 

Mooseman

Moderator
Dec 4, 2011
25,262
Ottawa, ON

HARDTRAILZ

Moderator
Nov 18, 2011
49,665
Not an Amsoil fanboy myself, esp after listening to the BS pitch to become one of the "dealers" that you just give them money to become. However if you really like their products and want to use their products, it costs you under $50. It takes virtually nothing to be a "dealer", but then you can make money off other enthusiasts!
  • Buy AMSOIL products at the lowest possible prices
  • Minimal startup fee
  • No inventory requirements
  • No capital investment
  • No employee expenses or requirements
 

mrrsm

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Oct 22, 2015
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As you clean up the Crankcase-Oil-Pan and Front Timing Chain Cover (it will also need a New Crankshaft Seal replaced, too) use Lacquer Thinner as a Solvent to clean off all of the Mating Metal Surfaces. Also, extra effort will need be needed to ensure that the Old OEM AC-Delco Engine Sealant gets thoroughly scraped cleaned out of all the Alignment Grooves on every Cover and Case Flange Surface. The AC-Delco Sealant is available via Amazon at the link below and no other RTV will work as well or last as long.

Ordinarily... this stuff would be applied to the Engine Block when it is inverted and on an Engine Stand... but since you will be working "Upside Down" to re-install the Crankcase from underneath the SUV... it will be more easily managed if you apply the stuff to the Crankcase Flange first. Follow the application instructions in the Manual to encircle the bolt holes and use a bead that is neither too thin nor too thick.

Be prepared to get the Crankcase quickly aligned with a few bolts at each of the four corners and press it in place for alignment and run the rest of the bolts down uniformly in order to "put the squeeze on the Goo". Avoid trying to use the Ratchet and Socket to Tighten Down individual Bolts or you risk cracking by Mal-adjusting the Case Mount alignment or damaging the Mount Holes in the Engine Block. Its important to have the Engine Block Flange Surfaces just as clean with some wiping with Lacquer Thinner and ensure that your Tools and Fasteners are ready in an organized manner because ...you will only have about (15) Minutes of working time before the RTV solidifies.

https://www.amazon.com/dp/B007Q0ZOHQ/?tag=gmtnation-20
 

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djthumper

Administrator
Nov 20, 2011
14,950
North Las Vegas
Many of my customers have come from the Old site and this site... And now you know.

To be fair, I have been gone for the past 2 years on an overseas deployment. That's why there was no activity on the boards...
My point is there are a number of you guys on the site and the old site. You may have a number of members that buy from you but there have been no preferred dealers recognized by the site and staff.
 

wes112565

Original poster
Member
Oct 4, 2013
13
Update :

I want to thank all theat has passed on your knowledge.

I managed to get the pam pff and cleaned up took awhile to clean out the lower end of the black but had it looking pretty nice, so I re-assembled it.

Started the engine and all was working wonderfully in the shop had apx 50 lbs oil pressure no lifter pecking and no rod noises.

Completed putting all frame work up and test drove, 20 minutes into the drive, my heart fell ... oil pressure zeroed out again but this time it fluctuates up and down then finally zeroed, Immediately killed the engine let set few minutes, started back up 50 lbs. started driving again and oil pressure zeroed again i let it set there at stop and listed for engine noise after a minute or so it was evident there was no oil pressure as i started getting engine noise, lifter started clicking so i shut down engine let set for about 5 minutes, started up and was able to make back to shop.

Im am thinking .. possibly the oil pump needs replaced, that maybe the bypass with all the gunk i had is fubarred or after looking at the pump in a picture which looks like a front pump on a automatic transmission is scarred and not holding the pressure.

Could anyone point me to the removal procedure of the oil pump on this unit , I would appreciate it greatly.

Wes
 

Mooseman

Moderator
Dec 4, 2011
25,262
Ottawa, ON
That really sucks big time because you'll have to pull the oil pan again. The oil pump is in the front timing chain cover and to get it off, the oil pan has to come off. Been there when I replaced the timing chain and tensioner.
 

wes112565

Original poster
Member
Oct 4, 2013
13
That really sucks big time because you'll have to pull the oil pan again. The oil pump is in the front timing chain cover and to get it off, the oil pan has to come off. Been there when I replaced the timing chain and tensioner.

I was afraid that would be the case, Its the oil sump screen bolt , it comes in from below, uuuugg

Could you point me to the front cover / oil pump removal procedure.
 

Mooseman

Moderator
Dec 4, 2011
25,262
Ottawa, ON
But of course!
How to replace I6 timing chain and tensioner

You can skip the stuff for the top side like the intake manifold and valve cover unless you also plan on replacing the timing chain. I would replace the tensioner as that has been known to fail on occasion.

It does sound like the pressure relief valve is borked. Hindsight being 20/20, I would have also replaced the pump at the same time just to eliminate that possibility.
 

mrrsm

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Wes.. I recently added some new images to my Photobucket of this very repair that might prove useful, These show where the Gerotor Oil Pump resides in the base of the lower inside section of the Front Timing Cover ... just as it is being removed, I'll be doing an 'autopsy' of the old OEM GM Pump by taking it off of the case over the next few days and installing a new oil pump from "Sealed Power". I'll add those to the ones in the below listed link just as soon as the work is done:

http://s557.photobucket.com/user/60...NEREPAIR/HARMONICBALANCEREMOVAL?sort=3&page=1
 

wes112565

Original poster
Member
Oct 4, 2013
13
Wes.. I recently added some new images to my Photobucket of this very repair that might prove useful, These show where the Gerotor Oil Pump resides in the base of the lower inside section of the Front Timing Cover ... just as it is being removed, I'll be doing an 'autopsy' of the old OEM GM Pump by taking it off of the case over the next few days and installing a new oil pump from "Sealed Power". I'll add those to the ones in the below listed link just as soon as the work is done:

Thank you kindly , I looked at some images and I def do not see away to do this without pulling the pan again, well at least all the bolts are freshly broken loose, only good point is see :smile:.

I appreciate the help tremendously.
Wes
 

mrrsm

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No problem... Brother... We're all in the same Boat when it come right down to it... Glad to offer you the Help...

And I would also suggest that you search around for others who have done similar work. Mine of late just happens to echo almost exactly what you need to know right now... and looking through what I have extensively documented and peppered with lengthy instructions will make some things a lot easier for you...and answer a lot of your questions all at once. (... but do try not to fall asleep when reading my Lengthy Tome...LOL).

I try to get as comprehensive as possible because of an obligation to serve more than one present Lurker, Future Member... and with all the questions answered ... it can help brings repairs to a speedy conclusion. So please ...have a look at this link and see what you find that will assist you further...probably around Post # 80 -> and it will steer you away from trouble:

http://gmtnation.com/forums/threads/engine-swap-2004-for-2002-gm-atlas-4-2l-motor.15786/

EDIT:

I was thinking about the idea that since you have already been inside this engine once that there might be a temptation to re-use the Seals and the Crankshaft TTY Bolt... and doing so would present some very real danger. The replacement bolt is around $10.00 from gmpartsdirect.com and the idea is to remember how much force was being applied AFTER it experienced the preliminary tightening of 110 Foot Pounds///it then has to be tortured into tightening up an additional 180 Degrees... which winds up beings closer to 700 Foot Pounds using a 22 MM Impact Socket...the Biggest Breaker Bar you have ...and 2" X 3' length of Galvanized Pipe as the means to coax it into turning. Once it is removed...it makes a Good Paper Weight.

And by the way... even though that Damned Crankshaft Bolt is a TTY... you don't need a Torque Angle Meter to squeeze down in between the engine and the Radiator... Just after you perform the initial tightening...(110 FPs and STOP) take a Permanent White Oil Paint Pen and Draw a Straight Vertical Line across the face of the bolt and let the mark extend onto the Front Timing Chain Cover as a Reference Point (avoid using the H-B Arms, as all three are exactly 120 Degrees apart) and slowly apply the last torque and keep checking with a Mirror to observe that line on the Face of the bolt until it inverts 180 Degrees and re-lines up again Arrow straight... Yer Dunn!

This evening... the Timing Cover Gasket Kit arrived to ensure that when I R&R the Gerotor Oil Pump from the Front of the Timing Chain Cover... that I have ALL NEW GASKETS to install... INSIDE AND OUT:
 

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wes112565

Original poster
Member
Oct 4, 2013
13
MRRSM,

Thank you for the information as i am new to this particular engine design.
I'm use to the old 350 Chevy and 351 W Fords.

Been a day or so since i actually worked on an engine.

So you are basically saying the Harmonic Balancer bolt is a throw away once it is removed, I would not have known this and would have attempted to reuse.

preliminary tightening of 110 Foot Pounds///it then has to be tortured into tightening up an additional 180 Degrees... which winds up beings closer to 700 Foot Pounds

I would have never dreamed this, thank you again for the great information, what does the abbreviation "TTY" actually mean?

I have already ordered a oil pump kit and front cover gasket set, will be adding a Harmonic Balancer bolt tomorrow.

Thanks Wes
 

Mooseman

Moderator
Dec 4, 2011
25,262
Ottawa, ON
That's Torque To Yield. Basically they are stretched to apply proper clamping pressure, which is why they have to be replaced.

I didn't replace mine in either engine (4.2 and 5.3) and the engine didn't explode :biggrin:
 
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wes112565

Original poster
Member
Oct 4, 2013
13
Update, OMG It Has Been A Long 5 hours, I know i probably went a little more in depth, but i pulled all of the front end off.. learning experience :smile:
Had to remove Fan, Shroud and Radiator as unit didn't see how I would be able to get the shroud and fan past the upper radiator neck.

Well I was able to get in to TRY and remove the Damper bolt.

New 1/2 drive impact later bolt still won, its still there all snug and tight.

Need some suggestions how to lock down engine / damper to try a breaker bar with a cheater on it to get it out. I still have not taken pan off maybe that will be the trick to lock crank down humm.

All suggestions will be appreciated.

Wes
 

Mooseman

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Dec 4, 2011
25,262
Ottawa, ON

mrrsm

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Wes... For a complete Step-By-Step set of Instructions... Please review Post #80 and #81 at the link below... But start by watching the Videos in Post #81 First... The Tool you require is the OTC Three Prong Puller Model #6667 along with the Biggest 1/2" Long Breaker Bar you can find, a 2" X 3' Length of Galvanized Pipe... and some means to prevent the Flex-Plate from Turning ...before you begin... Nothing else will work:

EDIT:

@m.mcmillan has thankfully discovered a less expensive, identical analog version of the OTC Model #6667 Tool Kit and has provided this link for access:

https://www.amazon.com/dp/B01AIRR4EY/?tag=gmtnation-20

The tool shown below is supposed to be specifically made to lock down the Flex plate... and before you begin... it will be imperative that the position of the #1 Cylinder Piston has NOT moved off of Top Dead Center from any other machinations you have tried so far... if that has occurred.... start ALL OVER again with performing enough rotations that the #1 Cylinder is right back on TDC...with the two Crankshaft Flats back in the Flat, Horizontal Position and the two Camshaft Sprocket Timing Marks showing Black Links there. Do NOT attempt to achieve these alignments by turning the engine Counter-Clockwise.

https://www.amazon.com/dp/B01I47QTNC/?tag=gmtnation-20

But ...if you pull out the Rubber Plug(s) that provides access to the two rear Crankcase Bolts and the Flex-Plate at the bottom where the Engine mates up to the Bell Housing of the 4L60E Transmission... you might be able to get two pairs of Long-Nosed Vise-Grips in that narrow space in there and pinch the outer edges of the Flex-Plate Starter Gear Fire Ring and have enough Mechanical Advantage to prevent the Crankshaft from turning while performing the TTY Bolt Removal and Installation Procedures.

Another tactic that might work is to get a 15 MM long Box End Wrench fixed on one the Three Torque Converter Bolts and secure it using a pair of large Vice Grips to hold the shank of the wrench handle right at the bottom of the opening to resist the any motion. The Box End wrench will have to be positioned first on the Driver's Side of the opening, left of center of the Crankshaft to resist the counter-clockwise removal force...and later re-positioned on a TC Bolt Head near the Passenger Side, right of the Centerline of the Crankshaft during the installation of the Brand New TTY Crankshaft Bolt.

http://gmtnation.com/forums/threads/engine-swap-2004-for-2002-gm-atlas-4-2l-motor.15786/page-2
 
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Mooseman

Moderator
Dec 4, 2011
25,262
Ottawa, ON
Engine timing and TDC, although desirable, are not critical since he's not replacing anything in the timing chain system, only the oil pump. The timing chain and its ancillary components are fairly robust and usually last the life of the engine, however there have been documented failures, including my own, of the chain tensioner so I would recommend replacing that part alone while you are there.

Yeah, it would have been ludicrous to spend $150 on that Spent-Moore tool so other methods suggested might work. Maybe sticking a socket through the access hole onto the flywheel bolt might work. Might need two people though, one to hold the socket at the flywheel and the other to break the damper bolt.
 
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wes112565

Original poster
Member
Oct 4, 2013
13
Maybe sticking a socket through the access hole onto the flywheel bolt might work. Might need two people though, one to hold the socket at the flywheel and the other to break the damper bolt.

MRRSM, the Biggest 1/2" Long Breaker Bar you can find, a 2" X 3' Length of Galvanized Pipe... and some means to prevent the Flex-Plate from Turning ...before you begin... Nothing else will work:

Awesome it worked great was able to get some help to do this tonight and it worked like a charm.

Thank you all for the guidance on this adventure.

I noticed after pulling the balancer off, that there was like a washer on end of the balancer and after Googling it I found a Gm part number 12578073, it says its a crush washer/seal is it really nessary to replace as I did not know it was there when i ordered parts and I only have the week end to work on it ( days off ) for another 11 days ugg.



I really doubt that i will be able to get in by Saturday if ordered tomorrow.


Wife is really getting mean about this thing now :smile:
 
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mrrsm

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Wes...

We are with you Brother... I know you are anxious to get things buttoned up and running... but unless the Old Washer fits neatly and firmly on the outer rim of the inner snout of the Harmonic Balancer... you will run the risk of having a serious Oil Leak. Sit the Lil Woman down and tell her..."The More Haste... The Less Speed..." Call around to the local GM Dealerships and see who has this relatively inexpensive component. It would kill me to imagine you having to take this engine down for a Third Time.
 
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Mooseman

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Dec 4, 2011
25,262
Ottawa, ON
Devil's advocate here :satan:

I did not replace mine with a new one with no ill effects.

IIRC it's a thin washer that is basically between the timing chain gear and the balancer? If that's what it is, I fail to see how this would cause a leak.
 
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mrrsm

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This link leads to a company that completely rebuilds Harmonic Balancers and provides an excellent retrospect about the purpose, origin and development of its designs going back 117 years ago. The in-depth article also gives some interesting ways to spot and diagnose the hidden causes of excessive engine vibration problems. Mentioned as being of particular interest to us will be the presence of unusual, shiny artifacts left in the outer Serpentine Grooves molded or machined into the Outer Mass Ring. There are quite a few posts here on GMT Nation that leave an often unsolved answer to “The Riddle of GM 4.2L Engine Vibrations” that cannot be explained in the absence of including the possibility of a declining Harmonic Balancer on engines with greater than 100,000 performance miles:

http://damperdudenz.tripod.com/id3.html

The main OT concern here is that with this “updated design”, GM cooked up an “Anti-Rotation Friction Washer” and it would seem impossible for something so massive and installed with such an enormous amount of force could ever manage to work its way loose. But the enormous forces at play along the centerline of the Crankshaft are such that without having a “Woodruff Key” to SNUGLY align and hold it in place on the nose of the Crankshaft… it CAN work its way free … and ruin the engine in very short order. Excessive engine vibrations, ruined Crankshaft Babbitt Bearings and of course… Engine Oil leaking from the Front Cover Seal are by-products of these is failures that accumulate over time and high mileage.

We already know how Massive and Heavy the average Crankshaft is when we take it out of an engine and lay it on the bench. Now imagine bolting the Harmonic Balancer on the end of it and then picking it up. You can get a better image of how hard it is for these two huge chunks of matter to stay “married” when they are back inside of the engine; one constantly vibrating while the other is fighting to absorb and dissipate the kinetic energy vibrations into heat energy AND slip and separate from one another at up to 5,000 RPM … you can get a dramatic idea of what a problem it would be … should they come apart or the Inner and Outer sections of the HB succeed in separating as well.

So in spite of the initial 110 Ft Lbs of torque and the additional 180 Degree TTY tightening force… the smooth inside diameter surfaces of the Harmonic Damper mating to the smooth outside diameter of the Crankshaft nose leaves an unfortunate ready opportunity for this loosening to occur. To counteract this tendency… The GM Engineers designed an “Anti-Rotational Rubberized Friction Washer” that sits snugly into, over and around a machined recess on the leading outside edge of the Harmonic Balancer snout. And once the huge TTY Crankshaft Bolt it tightened down, the combined friction between those two opposing points is the only thing preventing the Harmonic Balancer from coming loose and spinning freely on the nose of the Crankshaft. Without having any “Anti-Rotation Washer” in place… the proximity of the inside of the Harmonic Balancer can move close enough inboard to the Timing Chain Cover to make contact and it can shorten the lateral freedom of movement the Crankshaft enjoys inside of the Engine Block.

The GM Atlas Family of Engines are not alone in the use of this “Anti-Rotational Friction Washer” design, as it can be seen on the GM LS Engine series as well and in the case of the more powerful V-8 Engines… the exact same style of this seal… but theirs is “Diamond Impregnated” to improve its grip on its metal contact surfaces. This provides enough holding friction at the back-end of the Harmonic Balancer snout to securely hold the HB firmly and reliably in place while absorbing and dissipating horrendous vibrations whose amplitudes could climb rapidly enough to snap the HB right off of the nose of the Crankshaft and destroy the engine in matter of moments. Here is another interesting On Topic article worth reading: http://www.agcoauto.com/content/news/p2_articleid/273
 

wes112565

Original poster
Member
Oct 4, 2013
13
Update: I was able to sew this animal back together, and the wife is once happy again. Now on too the A/C not cooling like it should and back blower not working.. small details :smile:
It running as good as a new one ( knock on wood ).

I would like too thank all for your help on this matter and express my greatest appreciation for your in depth assistance and knowledge - experience.

This link leads to a company that completely rebuilds Harmonic Balancers and provides an excellent retrospect about the purpose, origin and development of its designs going back 117 years ago.

MRRSM , Thank you for this information , I will dive in and read up.

Wes
 
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