Rough idle and knocking noise from bottom of motor

mrrsm

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Jesus Wept... Brother... I know its looks pretty grim right now... But while Hoping against Hope... I'm going to continue to hold out for the idea that the problem remains with that Goddamned Flex-Plate. If the FPs were more commonly available... you could throw another one on there and see if it makes any difference. Its so strange how easily the Engine Fires Right Up and does not appear to shudder and shake. So I was wondering if you could find a Thin Wooden Dowel and place it at different positions along the top edges of the head and along the sides underneath to listen and feel if any noise either increases or decrease directionally.

The best way to Autopsy an Oil Filer is to Collect the Drained Oil in a few Opaque Containers like several Milk Jugs and the take a Third Jug and fill it up about three inches deep with some Fuel Kerosene sold by Harbor Freight for Campers and Old Timers still using Wick Lamps and then use a Telescoping Magnet to isolate any pieces of Piston Rings or any extraneous Ferrous Metals. Likewise by cutting the Oil Filter with a pair of Metal Shaping Shears and washing the inner filter wad with the kerosene, you can flush out Babbitt and small pieces of Aluminum and then open up each pleat for a more detailed washing and inspection. Swirl the stuff around and after shining a light through the sides you might spy some shiny reflections clinging inside the walls of the containers.

After removing the empty metal cannister and paper innards... use a Fourth Milk Jug with a Large Coffee Filter draped over a slightly more narrow opening in the Jug and slowly pour the complete residue of the gooey, loose contents down through the Filter. Then use some Fresh Lamp Kerosene to wash it as clean as possible and get a very close look at what is left behind for even the slightest amount of powdery, flaky metal whatsoever... and eyeball that stuff up close and personal with a magnifying glass to see what is what.

If the stuff is non-reactive magnetically...its a good bet to be Babbitt Material from either the large end of the Rods or from one or more of the Seven Main Bearing placements holding in the Crankshaft. And... If any serious metal deposits or broken parts and pieces are found: Well... You know how you can tell when its either very difficult, very expensive or very crazy to try to rebuild certain kinds of Engines? Have a Look at the following all too familiar "Seven Deadly Sins" related to the Repair or Rebuild necessary for GM Atlas LL8 4.2L Engine:

(1) Way Too Technical, Complex and Fussy and "Way Too Much Hassle."
(2) Way Too Expensive for Brand New and Required OEM New Parts.
(3) Way Too "No Substitutes Allowed" for TTY Fasteners.
(4) Way Too "Nobody Does This... Because Nobody Knows How Its Done."
(5) Way Too Many Broken TBs, Envoys, Saabs and Raniers with Donor Motors
(6) Way Too Much Easier to R&R in a Donor Motor once Prepped on a Stand.
(7) Way Too Expensive to Buy and R&R the Motor using an OEM Crate Engine.
 
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Mooseman

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Dec 4, 2011
25,259
Ottawa, ON
Could also be a main bearing which would not affect the rods. Good luck with the oil filter autopsy.
 

holytornado84

Original poster
Member
Feb 21, 2013
111
I found a mechanics shop here in town that's going to do it on Monday. They have got the tool that cuts the filter. Not sure how much they're going to charge, but they will know more about what is found inside of the filter than I will.
 

m.mcmillen

Member
Apr 29, 2016
554
Wisconsin
Can you pinpoint the area that the noise is coming from? Front, back, top, or bottom? Rod or main bearing knocks usually have a deeper sound to them.

Maybe your timing chain tensioner failed or a guide broke and the chain is flopping around inside?

Maybe something to do would be to get an oil sample. http://www.blackstone-labs.com/ is a great company to work with. I just started using them at work and I have been impressed.
 
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mrrsm

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A Tiny Hi-Jack...

Not much Good News for you lately for sure.... But since you are such an Avid Severe Weather Watcher... I just wanted to let you know that down here in Florida just this evening...we just had a very successful launch of the GOES-R Weather Satellite that will park itself in a Geo-stationary orbit over the Western Hemisphere at around 2200 Hours tonight. The satellite is LOADED Chock Full with New Real Time Weather Viewing Tech and Lightning Sensing Tech that will be a much better predictor of Tornadoes. If you visit Google & also use Youtube, right now, they have all the current dope on anything and everything related to the current GOES-R... its all there to see, Brother!

EDIT:
This Animation of the GOES-R Predicted Launch Activities and Post Arrival Actions shows what essentially happened last night after waiting 17 Years for a Technology that can essentially produce 1 Image Every 30 Seconds instead of 1 Image Every 30 Minutes as are the current limits of the other GOES Hardware:


And another Animation of the same Launch from a Different Point of View:


Finall...Here are all the other important links:

http://www.goes-r.gov/
http://blogs.nasa.gov/goes-r/
 
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holytornado84

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Feb 21, 2013
111
A Tiny Hi-Jack...

Not much Good News for you lately for sure.... But since you are such an Avid Severe Weather Watcher... I just wanted to let you know that down here in Florida just this evening...we just had a very successful launch of the GOES-R Weather Satellite that will park itself in a Geo-stationary orbit over the Western Hemisphere at around 2200 Hours tonight. The satellite is LOADED Chock Full with New Real Time Weather Viewing Tech and Lightning Sensing Tech that will be a much better predictor of Tornadoes. If you visit Google & also use Youtube, right now, they have all the current dope on anything and everything related to the current GOES-R... its all there to see, Brother!

EDIT:
This Animation of the GOES-R Predicted Launch Activities and Post Arrival Actions shows what essentially happened last night after waiting 17 Years for a Technology that can essentially produce 1 Image Every 30 Seconds instead of 1 Image Every 30 Minutes as are the current limits of the other GOES Hardware:

I was seeing some of my friends on FB talking about that. That would definitely be an awesome upgrade to the GOES satellite network. I use a visible satellite feed quite often before storm initiation to locate several indicators of convergence, boundaries and storm cyclogenesis. It only updates maybe 4 times an hour, so that would be awesome.

Got the results from the oil filter autopsy. The machine shop that did the work stated that there was nothing in the filter besides oil that needed to be changed. I think i will get out my shotgun microphone and run some videos from much closer angles under the car to see if it can be narrowed down that way. I also think I'll go ahead and get a borescope to look inside the combustion chambers to see if there are high amounts of carbon buildup that can possibly be cleaned out. Other than that, I'm happy to not find anything in the filter that would spell catastrophe.
 
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mrrsm

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Your instincts about the engine having a Carbon Laden Mess in the Combustion Chambers might be closer to the mark due to the High Mileage on your engine then most would imagine possible. The empirical images I have attached shows just how bad the situation gets over time. With enough of the Carbon Build-Up present... it can increase the compression ratio in the combustion chambers enough to cause Lower Octane Fuel to detonate and raise Hell in the cylinders,

I hold an unpopular theory that if you remove all of the Spark Plugs and after bringing each Piston up close to TDC… by spraying in the Foaming GM Top Engine Cleaner, it WILL dissolve the carbon down into a Black Muck that would either have to suctioned out afterwards ...or simply stuff absorbent Low-Fiber Blue Shop Towels to absorb all the Goo when the engine is gradually being turned over to prevent Hydro-Locking the Motor. With a substantial amount of this stuff inside...the Carbon will be loosened and completely dissolves in an hour or so. The Top Sealing Compression Rings will be exposed to enough of the TEC to dissolve all of the Gummy Carbon sticking them in place and loosen up the Rings.

The important part of the problem though, is finding the means to snake a slender tube down through the Spark Plug Hole and remove as much of this mess as possible before cleaning the Plug Holes and re-installing the Spark Plugs. Please note that GM Top Engine Cleaner must NOT be put into the Gas Tank or pumped through the Fuel Injectors. GM has a very elaborate TSB that describes the need for “precisely measuring the amount of Special, High Octane Fuel mixed with an EXACT amount of TEC in a Ratio that MUST be...blah...blah...blah”.

The problem I have with all of those “BG-44” procedures is that these mixtures have to be BURNED in order to work... and having seen how well the Foaming Spray flavor of GM TEC dissolves the Carbon without lifting a finger while it works… is remarkable… but the application I used involved having pulled the Engine Head first, then Gorilla Taping up all the extraneous openings in the Old MLS Gasket and using it as a barrier while I filled up each cylinder with copious amounts of the stuff.

An hour or so later… all that Ultra-Stuck-On Hard Carbon Crap was literally melted down into a Black Soupy Pudding that I simply wiped off and absorbed and sopped up like Turkey Gravy with White Micro-Fiber Cloths. As a result... it was absolutely unnecessary to use anything that required either Harsh Abrasives or “Elbow Grease” to get then stuff off of the Piston Heads. It really works just that well. So to use this spray down inside a hidden combustion chamber would require the additional attention needed to extricate that Muck, lest it remain pooled on the tops of the Pistons and Lock the Engine up and bend the Connecting Rods into Pretzels as soon as the Engine is turned over.

I think that vacating the spark plug holes and using the absorbent towels would be insurance against that Danger when Turning the Motor Over… but you would probably want some additional means of actually sucking that crap out using a thin clear hose and a small Shop Vacuum … just to be certain. The Pistons came out so amazingly Clean and Spotless that they actually revealed their machining marks and casting stamp order numbers and directional arrows for installation as though they were Brand New!

upload_2016-11-22_21-40-53.png

There would be no room for error when performing this task… The pooling TEC will NOT run down past the Rings after the “foaminess” liquefies… nor carry away that Gunky Mess further down into the crankcase in any substantial amounts… but nonetheless...if you employ this procedure… changing the Engine Oil and Filter afterwards will be an absolute must because any contamination might compromise PTFE Oil Seals located at the Front and Back of the Engine ...and around the Viton-Teflon Valve Guide Seals in the upper Engine Head. In lieu of using GM Top Engine Cleaner… You might try THIS flavor of the TEC… as it has an Extra Long Plastic Hose for inducing the stuff directly into each combustion chamber… But… I cannot swear that it will be as efficacious as the GM product...which is Absolute DOPE! I cannot recommend these creative and unusual tactics to everyone… so I’m sure other Members will want to chime in with some related alternative ideas and different suggestions for better ways to perform this task:

http://www.ebay.com/itm/CRC-Top-Eng...ash=item1ea6a52c83:g:OmMAAOSw~bFWOkpy&vxp=mtr
 

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holytornado84

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Feb 21, 2013
111
Well, after a long break to recollect my thoughts on this repair/diagnosis, I believe I have gotten a little ways further on finding the source. I also found that the trailblazer was practically empty with only 2 1/2 quarts of oil in the engine. She told me she checked the oil and had added a quart before driving to DFW (120 mile round trip) and back with it running like crap. A few days later is when I got to listen to it and told her to park and not drive it anymore. That being when I started working on it. I am thinking that she just added a quart and called it good without checking it or she just doesn't know how to check it properly. Either way, I got another oil filter and a quart of oil for it, installed and added the oil. It did not even show on the stick. Long story short, I went back several times to the parts store and got more oil until it was full so I could run it again. Started it, knock persisted.

After getting rained out for a couple of days, I decided to finally go grab a stethoscope from Autozone. Went outside to start and listen and guess what........ it starts misting again. I went ahead and hurried with the stethoscope check. I checked the back side of the oil pan and could notice a faint knock that sort of correlated with the same knock I am hearing without the scope. I then went down the exhaust and the noise started getting louder in the scope. I narrowed it down to a certain area that you can see in the video that I will attach. I know absolutely nothing about the internals of the exhaust system on these cars but it sounds just like something is in there rattling around. I shook the exhaust when I had it off of the vehicle though and nothing was loose or fell out.

I have 2 trailblazers of my own and I think before I tear her oil pan off and inspect the journal and connecting rods, I will tear my exhaust off of my 04 LS and install on hers to see if the knock persists. Anyways I figured I would toss this info on the forum to fill ya'll in on where I'm at now.

 

mrrsm

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It's probably academic to suggest this at the moment... but there is an online service at mycarmakesnoise.com that also sells an Android App for$1.99 giving access to a large library of Automotive Sounds to assist in diagnosing problem noise sources. I can't swear that the "Metal Bolt in the Drier" type sound that is so much in evidence with your TB circumstance will be listed there... but having access to the site might benefit other Members in the future as well. I believe you can use the site on line for free from a Desktop or Laptop... but having the App portability for the Cell Phone would make it easier for Real Time Comparisons.
 

gmcman

Member
Dec 12, 2011
4,656
Sorry I've missed updates on this thread, I wanted to comment on the knock being absent with trans removed. I want to speculate the knock wasn't audible because there was no load on the motor.

The noise sounds like a piston slap, could be a spun bearing but its a very pronounced metallic "Ting"..almost like the skirt slapping the bottom of the cylinder, if that's the case, it's likely caused by the very low oil level.

I would start the engine again and look at the firing order on the valve cover on the pass side....should read...1,5,3,6,2,4.

I would try another test, and that's to pull the number 6 coil lead, then the previous lead...#3. see if the noise goes away or changes with both cylinders dead.

Then move on to #5, then pull #1 and repeat.

Likely in the rear of the motor so start there and work forward.

By doing this, you won't get a sharp increase in engine speed as that piston leaves BDC.
 

holytornado84

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Feb 21, 2013
111
Sorry I've missed updates on this thread, I wanted to comment on the knock being absent with trans removed. I want to speculate the knock wasn't audible because there was no load on the motor.

The noise sounds like a piston slap, could be a spun bearing but its a very pronounced metallic "Ting"..almost like the skirt slapping the bottom of the cylinder, if that's the case, it's likely caused by the very low oil level.

I would start the engine again and look at the firing order on the valve cover on the pass side....should read...1,5,3,6,2,4.

I would try another test, and that's to pull the number 6 coil lead, then the previous lead...#3. see if the noise goes away or changes with both cylinders dead.

Then move on to #5, then pull #1 and repeat.

Likely in the rear of the motor so start there and work forward.

By doing this, you won't get a sharp increase in engine speed as that piston leaves BDC.
Well, what had happened was, the knock was not present after I had removed the transmission and exhaust. I replaced the exhaust but left the transmission pulled and the knock came back.

Thanks for the suggestion test. I figured the car might stall out if I removed fire from two cylinders at a time. I went ahead and proceeded with the double cylinder test that you recommended and I will upload the video here in the next 30 minutes. The knock seemed to have remained through the whole test, but at times it got quieter and then returned.
 

07TrailyLS

Member
May 7, 2014
423
Toledo ohio
Dunno if it was just the video but a HUGE change when you unplugged 4&2 cylinders.
 
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Mooseman

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Dec 4, 2011
25,259
Ottawa, ON
Same here. But the noise just sounds so dry and raspy to me, like it was the flywheel. Maybe it's just being amplified by the flywheel since the torque converter isn't there to absorb the noise.
 

holytornado84

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Feb 21, 2013
111
Dunno if it was just the video but a HUGE change when you unplugged 4&2 cylinders.
That's what I noticed. It definitely gets almost silent after unplugging 4 & 2, but then after a few seconds although quieter, it starts to come back.

Same here. But the noise just sounds so dry and raspy to me, like it was the flywheel. Maybe it's just being amplified by the flywheel since the torque converter isn't there to absorb the noise.
Sure wish I could start it without the flexplate installed.
 
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mrrsm

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It sounds so external to the engine that it makes me wonder whether or not the Bendix Spring Carrier and the Pinion Gear in the Starter are making indirect contact with the Flywheel and catching-releasing and spinning as the engine idles... I'm still hopeful that the sound is NOT coming from a Connecting Rod clattering against a cylinder wall towards the back of the engine.

Two other observations here:

I sure hope your Lady appreciates how diligently you have pursued her best interests at heart here. ...and

Your approach to taking these sequential videos is a PERFECT DIAGNOSTIC TECHNIQUE.
 
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gmcman

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Dec 12, 2011
4,656
Yeah, big difference with 4&2 disconnected. Not sure if you understood my thoughts on this fully, but you would still need to perform the test on cylinders 3, 2, &1.

Removing the cylinder that fires previous to the target cylinder is key. Continue the test, removing #3, then shortly after, the previous cylinder in the firing sequence.

Right now, #4 sounds like the culprit.
 

holytornado84

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Feb 21, 2013
111
Any updates? Did you try cylinders 3,2 &1?
Not yet. I am planning on doing a proper test after I have gotten a better understanding of the process that you use. This time I'm going to get a video from the top of the motor pulling each connector on video and have a secondary audio recorder underneath the car. Afterwards, I will synchronize the audio with the muted video from on top of the engine and it will be a much better test for others as well as us to use.

I am actually pulling the exhaust off of my trailblazer at the moment and will be taking it to her house later on to install on her car just to cancel out anything that could be going on internally inside of the exhaust.
 

gmcman

Member
Dec 12, 2011
4,656
Ok.

I guess to better understand what I'm talking about. ..you are testing the cylinders from back to front, starting with #6. After you pull coil #6, wait a few seconds and pull #3. Based on the firing order, #3 fires right before #6.

By doing this, you remove the rapid acceleration of the engine from #3 firing while #6 is rounding BDC, this keeps the skirt of #6 from slapping the lower cylinder as hard as it normally would.

Not always the case, but I think you have piston slap from a worn lower cylinder or a worn skirt.

Repeat on all cylinders.
 

holytornado84

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Feb 21, 2013
111
Here is the video of the cylinder test. I went in firing order pulling one cylinder, then the next. Then, I would plug the previous one back in and continue down the line. I am still noticing quite a bit of change upon removing fire from cylinder 4 right at the beginning of the test.

 

gmcman

Member
Dec 12, 2011
4,656
I think #4 may have a spun bearing or possibly a severely worn skirt. Looks like the test was run in order but may have been changed up slightly.

Not saying you have to do it again, but here's how I was explaining it for anyone not following it....

Firing order is 1,5,3,6,4,2

Pull #6, then with #6 pulled, pull #3, wait and listen.
Replace both leads.

Pull #5, then with #5 pulled, pull #1, wait and listen

Replace both leads

Pull #4, then with #4 pulled, pull #6, wait and listen.

Replace both leads.

Pull #3, then with #3 pulled, pull #5, wait and listen.

Replace both leads.

Pull #2, then with #2 pulled, pull #4, wait and listen.

Replace both leads.

Pull #1, then with #1 pulled, pull #2, wait and listen.

Replace both leads.
 

Mooseman

Moderator
Dec 4, 2011
25,259
Ottawa, ON
#4 is definitely suspect and the sound is being amplified by the flywheel like a bell. Time to start planning on an engine swap I'm afraid. :frown:
 

holytornado84

Original poster
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Feb 21, 2013
111
I think #4 may have a spun bearing or possibly a severely worn skirt. Looks like the test was run in order but may have been changed up slightly.

Not saying you have to do it again, but here's how I was explaining it for anyone not following it....

Firing order is 1,5,3,6,4,2

Pull #6, then with #6 pulled, pull #3, wait and listen.
Replace both leads.

Pull #5, then with #5 pulled, pull #1, wait and listen

Replace both leads

Pull #4, then with #4 pulled, pull #6, wait and listen.

Replace both leads.

Pull #3, then with #3 pulled, pull #5, wait and listen.

Replace both leads.

Pull #2, then with #2 pulled, pull #4, wait and listen.

Replace both leads.

Pull #1, then with #1 pulled, pull #2, wait and listen.

Replace both leads.
That's what I thought about after I did the test. I now understand the exact process you were suggesting be done I believe. I will be able to tinker around with that car for a while as I still have everything disassembled so a proper cylinder test, I still have the time to perform. I just don't understand why with the exhaust removed, it seems like the knock is not present.
 

gmcman

Member
Dec 12, 2011
4,656
I just don't understand why with the exhaust removed, it seems like the knock is not present.

Because when you had the exhaust removed, you mentioned it was removed WITH the trans removed. Remember when I mentioned it didn't have a load...the load was the torque converter/pump.

With a cold engine and no load, you will likely not hear a knock right away or it will be faint.
 

holytornado84

Original poster
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Feb 21, 2013
111
@holytornado84 I posted a thread with the exact same knock in my TB and was curious the outcome or status of your repair. Thanks!
Did not come up with a direct diagnosis for the knock. I am still going to replace the exhaust when I get a chance to see if that changes anything since I found no metal particles in the oil filter. I'll definitely post the results of that whenever I get around to it. Did you narrow the knock down to a specific spot with a stethoscope? Mine is coming from inside the exhaust about 3 or 4 foot back from the exhaust manifold.
 

mrrsm

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I was pondering your latest information and I would beg you for two additional Diagnostic Videos:

(1) Start the Engine ...and after removing the Oil Filler Cap... direct the Camera over the Open Oil Filler Neck for about 30 Seconds or so... to record the Internal Noises and then Re-Cap the Filler Neck.

(2) Take a 6" X 8" piece of Laser Printer Paper ...and while the Engine is Idling... Lay the paper evenly Flat over the Tail Pipe and keep a good grip on the edge of it as you watch for it to "flutter" as it would with a normally Idling Engine. However... if the paper "flutters"...and then suddenly gets sucked almost completely back up inside of the Tail Pipe... This would indicate that some of the Exhaust Valves were either Burned ...or the Seats were worn down or damaged in some way.

But without observing any of these "suction interruptions".... it would raise some doubt about problems with either bad Valves or Worn Engine Bearings on the Connecting Rods. One other artifact of Rod knock is that the sound of it Thudding lessens when the engine RPM is raised... and then it returns with a greater pounding sound as you throttle back down closer to idle.

Not trying for humor here... But if I didn't know better... I'd swear that someone either removed the Exhaust Manifold and dropped their Key Chain down inside ...or a few Quarters... (fasteners...?) or a small tool fell down part way inside of the open bell-end of Pipe leading to the Catalytic Converter before it got re-connected. So... Before you continue pulling the Exhaust off of your other Trailblazer... You might just remove the Three Bolts and the"Donut" and then run a Telescoping Magnet down inside the Bell-End of the Exhaust Pipe and do some "CAT-Fishing" first...and see if maybe you can "Catch" something... Huh? (Puns Intended)
 
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holytornado84

Original poster
Member
Feb 21, 2013
111
I was pondering your latest information and I would beg you for two additional Diagnostic Videos:

(1) Start the Engine ...and after removing the Oil Filler Cap... direct the Camera over the Open Oil Filler Neck for about 30 Seconds or so... to record the Internal Noises and then Re-Cap the Filler Neck.

(2) Take a 6" X 8" piece of Laser Printer Paper ...and while the Engine is Idling... Lay the paper evenly Flat over the Tail Pipe and keep a good grip on the edge of it as you watch for it to "flutter" as it would with a normally Idling Engine. However... if the paper "flutters"...and then suddenly gets sucked almost completely back up inside of the Tail Pipe... This would indicate that some of the Exhaust Valves were either Burned of the Seats were damaged in some way. and without any interruptions.... it would raise some doubt about problems with engine bearings of the Connecting Rods.

Not trying for humor here... But if I didn't know better... I'd swear that someone either removed the Exhaust Manifold and dropped their Key Chain down inside ...or a few Quarters... (fasteners...?) or a small tool fell down part way inside of the open bell-end of Pipe leading to the Catalytic Converter before it got re-connected.
I am fixing to pull the exhaust off of one of my trailblazers and try it on hers. I have just been having trouble with it because the underneath of my truck has a lot of surface rust and I have broke 1 out of 2 exhaust studs. I stopped because I didn't want to break the other one. I am fixing to try the wax method after heating it to remove the last nut.
 

holytornado84

Original poster
Member
Feb 21, 2013
111
Wax worked wonders on getting that seized nut off of the stud.

Anyways, I am now almost certain that she has an exhaust problem. I took the exhaust off of hers again and started the vehicle. using the stethoscope, I listened to various places around the engine block and could not detect a knock. Holding her exhaust firmly and also making sure that the donut flange was secure and not rattling, I violently shook her exhaust back and forth and bingo! There is the sound that we have been hearing.

I don't know much of anything about exhaust systems, but there is a broken down material coming out of hers that looks like it fits in the enlarged cavity that I was pointing to in the video where I used the stethoscope. I will attach a couple of photos of the material I am getting out of the exhaust in this post. Maybe someone on here will know what this is and why it's coming out of the exhaust. It's right before the O2 sensor so I figure it's some kind of material to help emissions.IMG_2055.JPGIMG_2054.JPGIMG_2053.JPG
 

mrrsm

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... and worth some extra "Bread" at any local Junk Yard, too. They recycle the Ceramic Honeycomb and Stainless Steel containers to reclaim the precious and rare earth metals... Platinum, Vanadium and Rhodium.. and will pay anywhere from $40 to $150 depending upon how much of that stuff is inside of those "innards". And as long as you bring along her vehicle title as proof of ownership before you set the old CAT on the counter, they will Pony up the Cash.

This video serves to "Show You the MONEY!" and explains the basic operations of CAT and why the rare earth metals are tucked inside of this clever "Gaseous Vapor Catalyzer" device. It is important to mention that in Basic Chemistry... when all of the chemical actions have been complete... You wind up with essentially the same amount of stable catalyzing metals that you started with ... and as such, they do not get consumed during the chemical transformations, retaining their elemental nature... and their value for reclamation.


PS... I wish we had some video of the damned thing before the Transmission Removal seemed so necessary... because if it were first suspected... I would have suggested leaving the Engine Off... sliding underneath on some cardboard and with truck safely "Jack-Stand" supporting the vehicle safely... I'd have asked you to take a Lead Pellet filled "Dead Blow Hammer" and VERY LIGHTLY TAP on the bottom area of the CAT cannister-container ...and listen for any Metallic Rebound Echos... Damn... I'm kicking myself now. Sorry about this Brother... because if you had heard that "Clinking, Clanking Collection of Colliginous Junk" rattling around down there.... it would have made life so much easier for you.
 
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holytornado84

Original poster
Member
Feb 21, 2013
111
Does anyone on here have any information on harmonic balancer/damper removal and installation? I specifically would like to know the appropriate tools needed and parts I should replace since I will also be replacing the crankshaft seal underneath.
 

Mooseman

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Dec 4, 2011
25,259
Ottawa, ON

holytornado84

Original poster
Member
Feb 21, 2013
111
I was reading a thread on the other side and it had some conversation about replacing a shim also. Does anyone know anything about this?

I did find a lot of information on the puller that you mention @Mooseman. Thanks! How about an installer. I can't seem to find much information on that part of the process or how to torque down the new balancer bolt without moving the crank.
 

mrrsm

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Oct 22, 2015
7,640
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Sorry for the late response… I was waiting to allow other informed Members the chance to address this issue first. Please look into Post #32 at this link for most of the cross-linked data and view the link to the Photobucket site that has all of the Sub-Albums that will show the Harmonic Balancer Installer Tool and other imagery for OEM part numbers as well:

http://gmtnation.com/forums/threads...ilblazer-2-wheel-drive-oil-pan-removal.16544/

If you look at the Sub-Albums shown on the Left Margin… there are many more images of OEM parts and tools to be seen:

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

EDIT: Tuesday, 01-24-2017

I neglected to mention the part that answers your question about “...a Shim” being involved in the R&R of the Atlas LL8 Engine Harmonic Balancer:

In its Original Design… The HB was a Three-Part Component that GM Engineers decided to simplify down to Two...and for their own reasons...they added in the need to install a Rubberized Shim that is installed on the leading edge of the HB snout and which is now indispensable for this installation. The attached link has been modified to include (3) images of the OEM package and I note that THIS HB comes equipped with that ‘special shim’ already installed. The shim can be ordered as a separate GM OEM component… However it cannot be used in concert with the Old Style Harmonic Balancer. The close-up images show the HB with the Rubberized Shim correctly installed on the HB and when the balancer is being guided onto the nose of the Crankshaft; care should be observed that it does not dislodge, misalign… or slide on first without remaining in place.


http://s557.photobucket.com/user/60...NEREPAIR/HARMONICBALANCEREMOVAL?sort=2&page=1
 
Last edited:

gmcman

Member
Dec 12, 2011
4,656
Did I miss something....was the catalytic converter the culprit? If so that would be awesome.
 

holytornado84

Original poster
Member
Feb 21, 2013
111
Did I miss something....was the catalytic converter the culprit? If so that would be awesome.
Yeah I know. Awesome!!! Exactly what I thought as soon as I took the exhaust off of her car to try and put mine on there to see if the sound would be eliminated. I didn't even bother putting mine on because as soon as I shook hers and heard what was inside, I knew that that was our culprit.

I am probably going to go to a junkyard and find one with relatively low miles on it because the engine has such high miles anyways. Now I just have to wait on the harmonic balancer puller and installer to get here and I will be back at putting everything together.
 

mrrsm

Lifetime VIP Donor
Supporting Donor
Member
Oct 22, 2015
7,640
Tampa Bay Area
Sorry for the late response… I was waiting to allow other informed Members the chance to address this issue first. Please look into Post #32 at this link for most of the cross-linked data and view the link to the Photobucket site that has all of the Sub-Albums that will show the Harmonic Balancer Installer Tool and other imagery for OEM part numbers as well:

http://gmtnation.com/forums/threads...ilblazer-2-wheel-drive-oil-pan-removal.16544/

If you look at the Sub-Albums shown on the Left Margin… there are many more images of OEM parts and tools to be seen:

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

EDIT: Tuesday, 01-24-2017

I neglected to mention the part that answers your question about “...a Shim” being involved in the R&R of the Atlas LL8 Engine Harmonic Balancer:

In its Original Design… The HB was a Three-Part Component that GM Engineers decided to simplify down to Two...and for their own reasons...they added in the need to install a Rubberized Shim that is installed on the leading edge of the HB snout and which is now indispensable for this installation. The attached link has been modified to include (3) images of the OEM package and I note that THIS HB comes equipped with that ‘special shim’ already installed. The shim can be ordered as a separate GM OEM component… However it cannot be used in concert with the Old Style Harmonic Balancer. The close-up images show the HB with the Rubberized Shim correctly installed on the HB and when the balancer is being guided onto the nose of the Crankshaft; care should be observed that it does not dislodge, misalign… or slide on first without remaining in place.


http://s557.photobucket.com/user/60...NEREPAIR/HARMONICBALANCEREMOVAL?sort=2&page=1

And here is s link to a "sister" design of this engine in the 5 Cylinder flavor...but which shows you how to secure the Flywheel from the bottom... and hopefully without the need for the $150.00 Special Tool...but with the clever use of either Vice Grips pinching ONLY the edges of the "toothy" parts...and not on the Mild Steel inner areas. I actually favor @Mooseman 's suggestion about using a 15MM Socket and Ratchet handle to secure the Flywheel from rotating but you will have to apply steady and even force in both directions so as not to damage the Aluminum Crankcase during the HB removal...and during its installation. Avoid using any High Power Impact Gun during this procedure as you can destroy the "Tuned Harmonics" of the Crankshaft in the process. The Crankshaft is not really designed to absorb any pounding abuse in this manner.

http://www.355nation.net/forum/i4-i5-engine-drivetrain/117081-oil-leak-front-engine.html
 

holytornado84

Original poster
Member
Feb 21, 2013
111
So should I replace the harmonic balancer, or just install the original back in its spot once I'm done replacing the seal?
 

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