SQUAREBODY C10 LS SWAP LASTED 3 DAYS.....THEN....KABOOM! 

JC your teardown of that motor proved it was a pre-existing condition. No fault of yours, my friend.

I feel like you could have found another salvage LS and installed it in the amount of time you spent investigating what happened to this one. You are blessed and cursed with being the man that you are. My idea won't work for you because you will never sleep not knowing if the next engine is any better than the first. I'm almost positive you are going to end up rebuilding this engine so you can be comfortable with everything inside of it. You have integrity beyond anyone else I see in today's world.

Definitely not your fault don't feel bad about it you do one hell of a great job in every video. Things happen you don't have x-ray eye's to see into the engine when you bought it.

You don't look like a putz at all. You put a lot of time and effort into that build, putting it together right. Unfortunately, it had a pre-existing problem and failed. Things like this just happen sometimes. The important thing is that you're making it right. That's what sets you above the actual putzes out there. Thank you for sharing with us! It was interesting working through the process of what happened.

What an absolute bummer! You took every precaution for a quality installation/exchange. Hopefully, the extra time you took will pay off on the re-installation.

This sucks but your on the right track to fix this engine. So it doesn't happen again. Looking forward to what you figure out on the cam and the next part of this rebuild. Thanks for sharing Mr & Mrs J.C.Smith.

I'm seventy three, missed out on the introduction of LS engines when wrenching due to my injury. I have heard so many things positive about these engines and so were supposedly the very best of best, even better than fords coyote 302 or what ever it is displaced at. My landlords have these engines in all of their toys. I can not get this concept of holding a engine against the rev limiter just bouncing like a good many videos show. Your inspector Cluso was right on and understand this heartache of finding a bad engine. I watched Scott with his "V 8" tare down with a flat head engine that supposedly was 60 thousand miles... which is about right for those engines didn't go high high miles. It had never had a oil change plus no filter on this engine so gunk was maximum overload. I knew before you did your teardown that you are too OCD to allow anything past your inspections. Your in simple words.... One of a very few damn good mechanics. Kind of in some ways still just learning about it as we go/went. I will still be a ford guy regardless of any hype about them. Even the best tho break down when you think millions of engines being made every year. I just wish that a One state that seems to run our country had not sold us out to china for cheap junk. I am aware of some foreign countries making changes to our vehicles that will help eventually like the folks making toyota who are going with the hydrogen fuel. After my using it, found out how darn cheap fuel can be. I have paid as low as a dime for a gallon of gas and only two cents for diesel in the fifties... SIN TAXATION!

As a professional RU-vid mechanic commenter with never personally opening up a motor of a truck… from what I’ve seen so far, and what I’ve learned from other channels, the ls is an interference motor which explains the valves kissing the pistons when the timing chain broke. The discoloration is definitely common due to the pcv system. But from what my “professional” chicken or the egg guess, this motor out of the donor truck blew a head gasket and was being run for some time with it blown and just having coolant dumped in it to keep running (I personally know someone who dumped a gallon a week into his truck for about a year) which at one point hydrolocked the truck, then got a head gasket, it might have been a year or 5 ago, who knows. Fast forward to when it blows. Rod snapped, piston kissed valve, timing chain snapped, and rest of the valves kissed the other 7 pistons, and debris cycled through for the couple seconds it took for the motor to stop, luckily it didn’t window the block. This is about the best case scenario for a blown rod

I agree J.C. Someone really didn’t take care of that engine. Just goes to show how important maintenance is on any engine. Sorry that happened to you guys.

Such a shame to hear about the failure J.C 😕 Very odd about the way the rod broke though 🤔 Previous lack of maintenance for sure. 🔧🔩

It’s not your fault you did everything right. I agree that it was neglected from lack of changing the oil and filter maintenance. I had a GM mechanic to tell me when you look for a LS engine the2003-2006 5.3 is the better one it has the stronger bottom end than the 4.8 because the bottom end on the 4.8 has smaller rods which are good for naturally aspirated power but not good for high performance use. I agree with one commenter that the engine must had a pre existing issue before you bought it.

Hi JC thank you for sharing

I agree, that engine had NOS introduced to it at one time.

You are an angel. Your character is beyond reproach... Be blessed, you rock, you are a god send...but, damn the luck..

Good video 👍 l liked the rod bearing part

Pushrod end wear is pretty common in LS engines. Even in some clean well maintained ones. Even well maintained ones tend to get a lot of carbon buildup in them apparently due to the EGR design. You can pull the pans on them when the rockers look spotless and the pan will have a layer of gritty sludge/carbon in the bottom of the pan. I think that gunk has a tendency to clog pushrod tubes casing the end galling. Some LS engines head gasket wouldn’t blow but it would have a clean split in the steel gasket which would allow coolant to fill a cylinder when it was shut down. Cranking one unknowingly would cause rod damage in short order. I think the engine possibly could have suffered a head gasket failure before you purchased it and the rod was damaged from hydrolocking . Most weak rods fail under deceleration . The cam bearings always look horrible in LS engines. Always. They are a great engine but like everything man has touched they are flawed. Fortunately they are relatively easy and cheap to build that will eliminate most weaknesses.

This is why we carry garage keepers/ completed operations liability insurance. Be thankfull nobody got hurt or killed. We all hate come backs. All we can do is pull our big boy panties up and make it right. This is how good shops operate. Thanks for your time. Pete in South Carolina

Thanks for the video.

The work you did to this truck is amazing , it’s not your fault , usually last engines are great running with a strong bottom end ,lack of maintenance is what did this engine . Lifters and valve springs are know to fail in last engines.

Good analysis

The depth of your understanding as evidenced by the sheer enormity of information put forth in your multiple plausible theories is inspring to say the least. Your willingness and ability to explain everything in great detail yet still keep it simple for the relative novice reflect the depth of your knowledge. I don't recall the exact wording, but Einstein has a quote that goes something like if you can't explain something to a 6 year old using crayons, then you don't understand it well enough to teach it. You, sir, are quite the master instructor. Well done. Love your videos.

You are a good man JC Smith. Integrity helps you to sleep at night.

I think that what you said is correct These new motors will not take a lack of maintenance

Wow that sucks. Good luck with whatever route you go hopefully the engine from the donor truck you bought is good or if you put in a rebuilt one hope either choice doesn't go the route this motor went. Things happen so don't beat yourself up to bad we can't tell how long a mechanical object will last.

Depending on year LS has AFM system where it shuts down 4 cylinders high speed so have put the heads swap cams because lifter failure do oil pressure bleeds off the lifters to activate the AFM system

hello j.c and mrs. smith it's is randy and i like yours video is cool thanks j.c friends randy and hello jeff dogs

Life happens thats out of our control, you do your best and atuff still happens, as long as no one dies or gets mamed its all good, things break, parts break, life goes on.

Probably a failed Head Gasket before you got it. Probably hydrolocked when it did, maybe they found forbidden milkshake then pulled the heads. Probably saw the the blown gasket, changed it out, reassembled, flushed fluids and the sent it. Except the rod in the bad cylinder twisted and cracked slightly, but showed no outward signs. You trialed it, beat on it, and it seemed fine. Buddy does what you're supposed to do on a hemorrhoid car and that compromised rod left the chat. Previous damage that would have required a very close inspection. Hemorrhoid vehicles are always a pain in the ass. Circle of life..... you just gotta get that next cherry LS off market place, most importantly the ad must include no lowballers, I know what I got!

JC I bet a whole Year's worth the money that engine had been hydrolocked previous of installing it in that truck which bent the rod witch made it weak and it snapped.the motor was junk before you started!!!! This is a good example of why you should always go through any engine before installing it in anything it's very cheap insurance and prevents things like this from happening 👍😁💯

You are a good man bless you

JC, you of people are not a putz. Honestly I wish alot more people would help others like you do. You don't have x-ray vision so don't beat yourself up. Lesson learned and that's it.

Tough luck, JC. Great forensic analysis and once again I’m impressed by your commitment to keeping your word; this world needs more Good People like you. The LS1 has built such a reputation for being the unburstable, tuneable V8 of choice that it has acquired the mythical status that All Examples Must Be Presumed Good; the reality - as you’ve unfortunately discovered - is that it is as susceptible to poor maintenance and/or substandard previous repairs as many other engines. Perhaps even a growing perception along the lines of “it’s eternal, everyone says so, so it’s fine for another 6K miles on this oil…”. Complacency reinforces and then later ruins reputations - or, more succinctly, is the LS1 now becoming a victim of its own success? I wish you better luck with the replacement LS1.

It’s amazing how much damage can be done in just a few seconds

the machine shop i use builds a lot of LS motors they tell me its common for the valve guide to break in the middle of the head and binds the valve and holds it open and piston hits valve then the next thing that happens is the next turn bends valve on the rocker arm side. i just as i mentioned before i am fixing one now that happened to it was cylinder 8 intake valve. also one of my dowl pins stayed in the head and head bolt was rusty. have it back together haven't started engine yet. but the dowl doesn't go very deep in the block on mine either.

Man that sucks, that’s the kinda luck I normally have!

liked yes not enjoyed, ya never can tell buying used, very informative

Don't feel bad it will come around

I feel really bad looking at the carnage. I can say this much you did nothing wrong some things you just can't foresee. Even the engineers sometimes make mistakes. If you think LS engines can be a nightmare at times, trust me friend BMW engines are way worse to repair. I do appreciate this video as a learning material for not only myself but others as well.

Dear J.C. Smith projects couple. 😱 Unfortunately Murphy's law kicked in pretty hard. At first I wanted to comment that you should consider to stop working for other people because it's simply too expensive for you. But then I realised that ol' Murphy could've also kicked if you had sold such a modified pickup truck. 🙈 My guess is that something already wasn't right with this engine when you bought the donor vehicle. How the connecting rod broke looks like a defect while the metal was poured/forged. Maybe the former owner knew about that, maybe not. Anyway: I hope that you will be able to purchase a good engine and put it in this long time project to get rid of it finally. 2) Hope at least Jeff is doing better. Thanks a lot for making teaching explaining recording editing uploading and sharing. Best regards luck and especially health to all 3 of you.

Well i agree with your theory.

When you get it fixed again give the whole truck a bath in holy water and have a priest exorcize it before you deliver to the owner 😂

A couple of things, I doubt if you can hit a cam shaft hard enough to bend it, they are Hardened Iron and extremely brittle. The bad rod could have come from water ingested down the intake after splashing through deep water at some time. If I were you, I would reach out to Eric at i do cars. He autopsies engines as part of his content, and could probably shed some good insights on yours. Dare I say, he deals in used parts and engines that he guarantees. I would definitely NOT rebuild that deal,, it will likely wind up as Round - 2 in the battle. Good luck J.C., I always enjoy your content, and Eric's,,, he's funny as heck and looks like Adam Sandler. No kidding, reach out to him, it does cost anything. 👍👍

I know no matter how many people tell you not to worry and it's not your fault ,That you will still blame yourself,,That's just your make up,,It's who you are,,And it's those kind of trates that show your an honourable person ,With high moral standards ,,Who cares about there workmanship ,And doing the best job they can do,,What happend here was totally out of your control,But the most important thing is that your willing to try and make it right,,And that's all any coustomer can ask ,,

I have been inside more LS's than i care to remember. Short of the broken rod it looks fine. The top of the cam bearing doesn't get ever get touched so they get gunk with time. The wear looks like any other LS.. high spots, wear from load, etc. Same goes for the dowels.. they almost always come out like that. Pulling the head bolts out can move them but i rarely ever have them stay in the block. Pushrods always wear with lack of oil... plugged up lifter is all that takes. They always just "shut off" under light load and break a rod.. mm hmm... sure thing customer lol. You win some you lose some. Did that cylinder hydrolock previously? Maybe. Hard to say!

From what I seen you did everything you could do things like this happens to everyone

That's a big reason I got out of the auto repair business. It is hard not to personalize the comebacks like this. I would usually eat the expense even if it wasn't something I did. I understand how bad you feel.

Sorry to hear about the motor I you make a special effort to make it right for the owner. K have a feeling to that the rod wasn't right defect or ? The broke didn't look right I heard that guys that beat on them at the track put beefier rods as low buck up grade maybe its best to fix it if you get another motor would be trading one problem for another.I'm sure you'll do what's best what ever it!

35:00 that bend/twist in the rod screams hydrolock to me 43:00 that rod has been bent for a while

I don't know LS engines all that well but, were the holes in the bearings across from each other, and if not were they installed upside down so the holes in the block didn't line up.

Lifters are a common failure on LS motors i lost a low mileage 6.0 dropped a vavle out of nowhere like literally shut the truck off came out of house turned the truck on and it was locked up

Its a machine they break, it happens. Still a pain the rear.

So sad to have this happen you would need a crystal ball 😢

At least non of the bolts had time to get rusty that is a plus

forgot to mention they also say the cam bearings sometimes rotate and cut off oil sometimes

Man that looks like it came in there

Maybe it was a casting flaw in the rod. Yeah, odd to go 200k miles before letting go, but does happen.

just as a question did you pull the can bearings? just ODD that oil passage hole inst lined up to a hole and the burnt oil on them

i have watched heaps of your videos and a lot of the time i thought you went above and beond in your repairs on any thing you touch but in aust we have a saying that shit happens and its not your fault. but im waiting for the rebuild because i dont think you would even be happy with a crate motor let alone a salvage one so best of luck and i will wait for the out come

J.C.sorry about the heartache .I know how much it takes out of someone to do this type work.I have done it all my life.My opinion is that rod was hurt by the look of the rod bearing .Some times you just do not know with a used or new engine for that matter.The customer may pay for the parts and you take care of the labor ( just a thought) .

It stinks that you got a bad example of ls but you'll give it the J.C.treatment, know it's done the way you want, and it'll be back on the road soon. He'll be happy.

The broken con. rod had been bent, probably from "hydraulic" event from a head gasket failure in the past, this is shown by the wear patter on the rod bearing. Its all down hill from there.

19:03 I doubt that’s what he thinks of you Mr. Smith. I would agree with you if you refused to make it right then yes. Things happen and unfortunately no one has a crystal ball to predict things like this. I know it’s upsetting and a kick to the gut but at the end of the day you’re taking care of it the best you can and that’s enough. I’m sure the customer would agree with me on this one. Try not to beat yourself up to bad over it as my grandpa told me once it’s just a machine they’re replaceable.

Very rare to see an ls have problems with the bottom end parts. These engines routinely go 300,000 miles between rebuilds. They are raced at hp level of. 1,000 or more with surprising durability. Most usually bent/broken rods in these engines can be caused by excessive rpm and or horsepower or faulty injectors in engines used in racing(cars using methanol) resulting in the engine hydraulicing . It’s not uncommon for these engines to run camshaft lifts exceeding 0.600 inch. The engines with the 4-6-8 capability had some problems with the cylender delete valve train lifters which could cause some of the problems you are seeing.

Cause is shitty parts I always replace timing chains in an ls but it smashed some valves also rip it out for a new one

Are there date codes on the bearings? I wonder if someone was in there before. I thought the early 5.3 s had cam and lifter problems. Are the cam bearing lube holes not clocked right or is there only 1 hole used

If you were to suspect that the heads were off previously, could the incorrect length pushrods have been used? causing the collapsed lifter and football shaped wear?

I did not see the plastic barbell that restricts oil flow .

I think i would have the crank checked for bend and twist along with the con rods get a new cam... replace con rods as required ..valves as required... new bearings and pop her back together together. I am pretty sure your xray vision is as good as mine so you wont see inside another doner engine... at least you will have peace of mind building the one you have properly.... and i KNOW you do things properly. Sorry you have had this problem.. you certainly dont deserve problems with the way you work.... i am finicky with guys working on my stuff... i would hire you to do my vehicles in an instant

What does the lifters look like. We drag race LS motors in Stock the lifters are the weakest link

Sherlock Smith I presume.

😎👍

It almost had to be hydrolocked I wonder if it had a leaky injector that got stuck on. The stock chains are pretty strong whatever u do dont go double roller get the c5r chain and do the trunion upgrade on the rocker arms.

Shit happens. Its just not fun when it happens to you. Especially on a charity job. Just be thankful you can afford to do it for him. Im sure he is thankful for your help. Good things come to those who help others.

Having an engine fail that you worked on is a hard pill to swallow. You'll make it right & move on in no time flat . 👍

For the life of me I can't understand why folks pull these engines out of the junkyard and throw them in a daily driver. I pulled a lq4, and I took it straight to the engine shop for the works.

sometimes best not to think

Bummer. Sorry about your luck, you got a pig in a poke. I know you'll make it right.

The 4.8/5.3/6.0 motors are known for lifter/cam bearing failure. I have seen these motors with near perfect service have trashed cam bearings before anything else failed. Also you hit the nail on the head with the down pins. Those heads have been removed before. I'd say about 5k or so miles before you got ahold of it maybe less. Those pistons are pretty clean and so is the motor. I believe the abnormal oil marks on the c bearings and the sludge came from it being run over heated and cooked the oil. The twist in the rod definitely tells me that rod was compressed above it's limit at some point in time. I see these motors fail like this all the time when they are turbo'd due to too much boost. That rod is a text boom example of it. I'm sorry you got a lemon of a used motor. I don't care for that LS platform myself. Any motor I have to pull heads to service lifters is a no go for me lol. I believe you are 100% correct. The rod let go, it hit the block, pieces jammed up the cam, chain snapped. All in all, a failed head gasket that the previous owner drove on and continuously ran hot was the beginning of the end for that poor motor and you got stuck with it.

Do you have anyway to see it was tuned to increase the rev limiter. Looks like over reved and valves floated.

36:35 Yeah the cam bearings need replaced because you looked at em. Cam bearings are only bad if ya look at em.

Someone at some point in it's life beat that engine senseless!!! The way those rod bearings wore, says that those rods are oval shaped now. Those intake valves have been HOT!! Those cam bearings have been known to spin and cams known to bend. Brand Racing Engines Channel has some really good content on these issues, he also does everything old school cool!!

Color on one side of the engine will always be darker on the pcv side. Sorry about the failure. It’s always an investigation when something happens

Someone previously blew head gaskets hydrolocked bent rod....

I say this knowing that I wasn't there but I find it hard to believe that that thing just "shut off" without warning, I'm not saying I think he was abusing it but a broken rod slapping the windage tray is noticeable.

i think at one time the engine hydro locked for some reason cracked the rod and then it finally broke

I would like to remove those cam bearings and examine the block. I suspect that the bearings were installed incorrectly.

I suspect that when the chain broke the cylinder with the broken rod was on the firing stroke, when it came back up the exhaust valve didn’t open and it broke the rod

I wonder if that rod suffered from a previous hydro-lock event at some point?

The shiney sides on the rod bearings may of happened after it blew. The missing teeth on the timing set tells me that engine was turning at speed. The hung open valve might be trash running through the engine after failure

No good deed goes unpunished 😐

Have you talked to (import apart ) they take engines on ( I do cars ) breaking them down to investigate their failure

Probably going forward don’t install any more used engines unless customer provides the engine he has picked out and then no warranty.

Ls motors do have head gasket problems.Maybe one head was changed either way the rod was bent and twisted which is exactly what happens when hydro locked.This damaged the rod which eventually caused it to fail in 2 places and that piece jammed the cam.For sure not your fault.

The noise he heard could have been the timing going out of whack and pre detonated it so bad that it knocked so hard it bent and then broke the rod.

For piece of mind I would just put a rebuilt through it for good reliable power if the customer can afford it

Hey JC. Don't beat yourself up man. I bet someone got into that motor and didn't do it right, before you got it.

Lifters left chat ?

I bet that a previous owner had it pegged on the limiter, either maliciously (ie: burnout or drifting) or during an accident and the accelerator pedal got pegged. The engines are well known for their standard connecting rods to not withstand sitting on the limiter. The conrod got stressed but not quite to breaking point, and just let go on J.C's watch

Wassup

Well, at least it's only mechanic'ing, not fabricating.