Wow, it looks like someone has dumped a load of stop leak in the cooling system to keep it going and then got rid of it before it totally failed. Looks like it was previously owned by a complete hack. The new owner has ended up with a real lemon.

Hopefully the customer comes to the realization that the best thing to do is just to let you do a complete rebuild of that engine.

I had a good laugh at how you said "whoever put that in is a moron " no rage, frustration, emotion, etc just very matter of fact 🤣🤣

Can we start a fundraiser to revive this engine? I really want to see a mini-series on this thing!

The most discouraging thing to me when dismantling something is seeing a crap ton of RTV/silicone. That’s a sure fire sign It’s had a hack working on it

Can't believe that truck could even crank with battery cables like that. We have 4 batteries in our trucks and we have had ONE SINGLE bad ground wire prevent it from cranking over with fully charged batteries... crazy. Thanks for sharing Josh, hope to see more of this!

Topping up the coolent with hard water every morning will do that to an engine and radiator. The water boils off leaving calcium and crap behind. I'm liking these lastest videos where you are looking for faults and remedies in customer's trucks.

Starting as an apprentice mechanic at a CAT dealership this month. This channel has been awesome! Thanks for taking us along for the ride!

Once I saw the way those batteries were configured, it spoke everything about the maintenance program (or lack of) that the previous owner had. All of that mud/gunk in the coolant system sure looks like radiator stop leak additive as well as electrolysis. The problem at this point, any minor repairs made to try to keep it limping down the road is just putting lipstick on a pig. I love troubleshooting videos like this though, so thanks for posting!

That radiator sealant in a bottle is nasty, about the only way to get it out is to boil the dismantled parts and shoot boiling cleaner through the ports and gulleys. It is nasty stuff. She is ready for a full rebuild, probably not what the owner wanted to see. Another educational video, thank you Sir. Stay safe and healthy.

At 1.3 million miles them liners dont owe anyone a damned thing lol. Kinda impressed at how resilient this motor is with all the issues

So just found your channel today from a lucky KZfaq recommendation. Been binge watching your videos and man it’s been awesome! Incredible detail and your great at helping us understand what’s going on. Really enjoying your amazing work. Thank you!

Looks like a good candidate for an out of frame rebuild and acid dip

Love my Airlift...thanks for recommending it. Good advice that the cooling system in a diesel deserves regular proper maintenance and the consequences of ignoring it. Cavitation is real and destructive.

The dark diesel is likely used oil, fill it with off road diesel and throw in a few gallons of used oil to mask the dye.

The mud in the block is block seal. We have two trucks with cats that the whole system looks the same way. My buddy who owns them used it and learned why you shouldn't afterwards. It's been over 8 years many coolant changes even a rebuild on each motor you can't get rid of the block seal once it's been put in the motor

Pretty engine awesome Josh. Such a treasure of destruction. Perfect for showing all the things engines of many miles have. Complete rebuild and paint will be great for a next million miles. Hopefully customer does it. Cheers Josh 👍💪🍻

I'm a John Deere C&F mechanic, I get a lot of engine stuff out in the field. Best thing I've ever use for broken manifold studs is this special welding rod called x-tractalloy. The flux stops the weld from sticking to the threads, the heat frees up the stud, weld a nut to the end. Best shit ever.

Righteous start to Sunday morning. Thank you.😊

As usual, a well put together video. Thanks for sharing

Whenever I wonder if I should return to the diesel field, I watch your videos. I get my fix living vicariously through you! Appreciate the uploads

I had a NTC CUMMINS that Pittsburg power built to 550 hp . Every year I would drain the coolant then fill it with tap water and add cascade dishwasher soap and run it at idle for about an 3 hours . After removing the bottom hose and rinsing the engine out good I filled it with 5 gallons of distilled water 2 bottles of the additive,and 5 gallons of coolant .At 1.5 million we rebuilt the engine and the mechanics were amazed at the liners there wasn’t a single pit on any of them in fact the mechanic wanted to put new rings in and reuse them . Preventative maintenance goes a long way to get longevity out of a Diesel engine. We also used synthetic oil regularly changed every 22,000 miles with wix xe filters .

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As like the rest of your video's, Very interesting!! Be nice that the customer want to rebuild it, like to see that #6 Sleeve from the water jacket side!! Thanks for taking the time to record and share!!

I love Detroit.. I have a 3406B mechanical cat .. but by the time u finish watching this guy videos he will turn me into cat mechanic .. love your videos..and your honesty

Some people mix a bit of ATF and oil with their fuel because there's lower lubricity than it used to have

Looks like reman time. I put a one way flow valve in one last week on the suction side and it helped. The coolant by pass hose I like to use a 7E0759 instead of the 9Y4104. It is longer and cheaper. The glue between the cylinder block and front plate is sort of the old recall service letter. PS5290, PS5291, PS5292. When Cat wanted to put epoxy over the leak and try to seal it in. When the 5EK's first came out the fuel flow was as you described. Then the aluminium piston's started failing. So new software came out and the fuel flow was reversed from ECM to front of head and returned out the rear. I have swapped out broken EUI springs when the customer can't afford a new EUI or putting a new one in with a bunch of worn out ones causing a cylinder to fire harder then the rest. He also needs a low coolant sensor, did not see one in that radiator that is junk. Never seen head bolts bubble, new one on me. Glad you got it, and not me. Ever do a high speed five cylinder cut out test?

My favorite mechanic! And this is even though this as I own a Toyota and a Freightliner with a Cummins 14! I'm so glad the William Tell Overture is back! I am very puzzled how the coolant to be so unaffected when everything else in the pulley system seems so affected by us large

It may cost a pretty penny to rebuild this engine, but it'll be a real money maker. Pre emission is the only way to have maximum uptime.

What a nice list of problems you have found .👍👍👍👍 Probably not bad for the moles on it .

Agree with the comments about some sort of 'stop-leak' in the cooling system. In addition, I've seen similar buildup/corrosion in a couple locomotives where they were running straight untreated water from questionable sources (one unit had about 25% of the radiator entirely blocked off by sludge buildup).

I have this engine for my shop class right now, I have the pistons out and the cylinder head sitting on tables right now. So excited to see you talk about it😅❤

As a 5EK owner, thanks for the video. Always learning something new. Thank you!

That looks like a complete rebuild, or trip to the scrap yard for that engine. Only time I ever seen an engine that looked like that, was on a 1 ton that came out of the west Texas oil fields that they had been dumping crude oil into. But that was a gasoline engine oil galley, not the cooling system. Yet I seam to remember a 1972 Ford F-100 that had a cooling system that looked looked similar, but someone had tried to fix a cooling leak with raw eggs.

Im lovin this one. The first owner that handed me the keys told me this truck should run a million miles.

Great videos I've learned so much, please keep them coming,thankyou and take care.

Cavitation from coolant side of liner when cylinder fires it creates a shock wave causes cavitation . Also block heater electrolysis we had a Cummins get holes through from block heater electrolysis since payloader was plugged in all winter for snow removal .

Serious lack of schedule maintenance. Especially the cooling system. That gunk I have seen on engines using a coolant filter with additive. Over concentrating the nitrite additive.

That brown coolant goo looks very familiar. It looks just like when someone uses those head-gasket-in-a-bottle type chemicals. They rarely work but they do leave a hell of a mess for the next guy

Love the channel man, glad I found it!

Love your videos. Looks like hackery isn't limited to regular cars and trucks!

Very interested in the follow ups and finish of this big project! Awesomeness

Pretty damn impressive honestly! It’s obvious at some point previous owner said screw dumping money into it if it doesn’t NEED it, it’s closing in on 1 million miles anyhow.

Such great videos, I have a Cummins isx, but I still learn a lot from your videos🚛🚛

Great video Thank you for the recommendation on silicone around toilet 😜. Thanks again

I wanted to be a diesel mechanic when I was in high school. Ended up joining the Air Force and became an aircraft mechanic instead. Never know where the road will take you sometimes.

The number 6 cylinder/sleeve wall reminded me of something that I saw in my dad's 1973 Oldsmobile Omega Rocket 350 Rocket engine (gasoline). The engine started overheating in 1998. Pop had a hydrocarbon test in the cooling system. Pops replaced the cylinder heads. The need for new heads was surprising because his grandpa had the engine completely rebuilt about 30,000 miles prior to the overheat problem. This didn't eliminate the presence of hydrocarbons in the engine coolant. We had the heads pulled and inspected the cylinder walls. We found a line in one of the cylinders near a water jacket. The reason I mention my dad's experience is the fact that we found the cylinder to be just as smooth and physically undetectable (to the touch) as that which you found in your customer's cat engine. #AdeptApe

My dad's 2006 Kenworth W900 has over 1.6 or 1.7 million miles on it. Somewhere between 1.6 and 2 million I remember when I last checked. Just 1 million is nothing to his truck. Right now the company he works for is about to go bankrupt, the owner has millions but won't take any of his money out of his account and put it in the company's.

Hope the customer has the money to fix it since it would make a great video. Unfortunately most in this situation will have the truck parked in the lot for a months before it finally gets towed out never to be seen again.

Good diagnostic skills , white smoke usually always low compression , dribbling injectors , un-burnt fuel. That was so close to going up in flames. People underestimate the problems loose batteries can cause. Trucks reach a point at that million mile mark where everything wears out. "Bin" it my advice , just gonna be a great big money pit for the owner, it will never end (repairs)

Great video, really enjoy your expertise and knowledge !! I feel like I'm in the Shop working with you !! Thanks 👍🏽 PS, looking forward to Part 2.

Just an old wrencher Ya can tell you are serious about your job .n take pride in what you do Keep on Wrenchin

I'm mechanical engineer at a railroad repair facility and we discover such sludge very often on neglected engines. As some of our client accept to pay the price for regular oil and coolant analysis, we have discovered that such engines even after flushing the cooling system and putting fresh coolant, within next two months, coolant was bad (coolant was still preventing the even from freezing but wasn't protection from corrosion at all!!!). The chemist from the company that does oil and water analyses for us explained that it's silicate coming from coolant that got way too old. This creates a thermal barrier and your cooling system become way less effective. He advises us the rinse such engine with soda and let the engine warm with it, cool down for two hours, rinse with clear water, flush again before filling with fresh coolant. This process worked great, and we could see a real difference with engine temperature and analysis are way better. To reduce the risk of such sludge to appear, we now ask our client to use silicate free coolant (but that's way more expensive and they don't always agree).

"Must be the same person" savage. But true.

I was actually driving that Mack when it happened lol. Engine went kaboom and then I went to sleep that night

Electrolysis would lead to the symptom in the number 6 liner. Especially after seeing the battery situation. Those engines really need to be grounded properly and checked often. I’ve seen a lot of problems just with electrolysis over the years. It’s not talked about enough. Often times guys top up their coolant with regular tap water that has minerals and other foreign contaminates. Same thing goes for when you are with a lady of the night. You never know what you are going to pick up til it’s too late. This is why you have to make extra sure you wrap it up before follow through Lol! Or just get the heck out of there. Seriously. Once you contaminated the cooling system, it’s all over and you get those results like this system here.

The company I worked for regularly used sno- bowl to clean out the cooling system. Not sure if this is a good thing or not but this was the 70’s and we’re talking two stroke Detroits.

Excellent video, I had a Cat 5EK engine in my 1994 Peterbilt, it was one of the first 10,000 EK's built. I had no trouble with it but Cat put a new camshaft in it free of charge, they say said Cat had trouble with the 1st EK's cams. I put 780,000 miles on it before it starting getting water in the oil. Had it overhauled & while tearing down they came to find out the deck was out of spec. so the engine had to betaken out of truck, as long as out they checked my crankshaft & it had a crack in it. New crank had to be put in it, but I would have had a complete overhaul done on that engine with a crank that surely would have broke at some point and we never would have found it if the deck would have passed specs. Costs a lost more than planned but still better to find the cracked crank ahead of it breaking. That very same motor is running daily since the out of frame overhaul & has another 600,000 miles on it. Those E models don't get the credit they have coming in my view. It's all about the C15 and the 6NZ.

Give your recommendation on what's best for the custumer to do! Great video! 👍🏽😃

You had me at Huey.

I think it'd be great if all mechanics recorded video while they work on your rig and the customer be able to watch it.

I recently found silicone used on a fuel fitting on a DD15 head. It was the return line but still someone used silicone instead of the o-ring. It mildly infuriated me.

Just what you want to hear your mechanic say: "never seen that before"

LMFAO at the numbering. Great video as always dude!! Also, that destruction of the week is absolutely bonkers. I have never seen that before.

3406e is one of the Best engines ever made, i had it on my 1st truck only thing i replaced was injector cups and that thing was a beast at 455hp

I had a similar fuel start up problem. Was leaky return line splitter valve and fuel pump. BXS though.

Unless the factory service manual calls for silicone sealant, I do not use it. Static elastomer gaskets and O-rings do not normally need anything to "help" them seal. Occasionally, a FSM will require a SMALL bead of silicone at the corners of a gasket or where two separate ones meet, but that is about it in my experience. If I have a paper or composite gasket and I need it to stay put on a vertical surface during reassembly, a little Hylomar Blue works.

I had pictures of a big cam Cummins that number 2 piston collapsed and the rod blew the front 2 cam follower boxes and the corresponding part of the cam out of the block, cut the pan in half and flattened the front of the oil filter on the other side. Driver said it felt like a grenade went off under his feet. I picked up a piece of camshaft a couple hundred yards back up the road.

Hi Ape. Great video, can’t wait to see the results if the owner moves forward with the repairs. I have a C15 MBM08945 S/N. We are have a problem where it runs great, all of a sudden dies, give it anywhere from 0-15 minutes and it’ll fire up and run great for 5-30 minutes then die again. Fuel pressure is great, we checked and cleaned all electrical for corrosion, cleaned the grounds, there are no codes on the ECM and the engine runs strong and normal, when it’s running. Any idea where to go next ?

Love you vids, been dealing with a possible ecm issue. I run a vac on a feed trailer, while vacing truck will die for no reason. No codes or lights. Starts back up runs for awhile does it again or won't for rest of week. Never does it going down road or unloading the feed. I have a scan gauge hooked up for some extra gauges the code reader will get codes for low current injectors but doesn't show up when dealer hooks up to ecm. Been jigging wires for ecm power will never die. Everyone says ecm wires from battery box, but when they go bad usually won't start back up and you get a check engine light. I'm baffled. Thanks

Thank you very much.

Quality video, that thing is about ready for the scrapyard. You've got your work cut out there, just sorting out the coolant system. It is going to need a bit more than couple of dishwasher tablets to clean that system. With a million miles on the clock, the engine won't be the only issue with it. That is a money pit. I worked on a Scania coach with 1.6million miles on the engine in very similar condition. Covered in sealant, leaking every fluid known to man. I told the customer, the blown £4,000 engine ecu was the least of his problems.

I've had quite a few ISX engine get the head bolt bubble like that when taking loose

Do a lot of people just leave their trucks because they don’t want to fix the engine or whatever is wrong with it?

Funny becauae silicone doesn't belong around toilets either since the wax ring should be sealing the drain and if its not and you just silicone around the base you are rotting out your subfloor.

I honestly think that it needs to come out and hot tanked and a complete Platinum overhaul done on it. Ps. I have a complete 5EK parts engine over here on the other side of the state. 😉

Seeing the state of this engine it gives me Hope regards my VW LT35 2.5 SDI…

That destruction was wild 😮

Nice Vid. Thanks.

I just did a 1.3 million mile 379.. was putting out almost 17 volts..lights were glowing 😂

Great find for the apprentice to see.

We bought a tractor once knowing that the coolant and oil has mixed before and they still used it for a while, so it was overheating. What solved it was of course a new rad, plus a flush with diesel, the oil that was caked on the walls of the coolant passages came off in a rather spectacular way. It’s wet cylinder so a couple years later I cleaned it up some more with a wire wheel while it was being rebuilt.

It’s always #6… never fails😂

Quite the potpourri (I’ve never used that word in a sentence before)

Oooo Oooo…. Sunday with the ape! All is right with the world. 😅

I mean, after that LONG period of service, I'd say she has now earned herself a complete overhaul. Might as well just do it right and do it all at this point!

Are those batteries new? If the cranking power of the battery is low, not the voltage from alternator, there is a chances that fuel pressure doesn't build properly by fuel pump. The crank voltage will kept on dropping the more you park it, hence owner may felt like low pressure after long parking but you don't see them if you kept on starting now and then. There will be white smokes because fuel pump coudnt bring fuel to injectors. Learned this from my diesel car but not truck. And ya, I could be wrong in this scenario as well, but just a thought.

Total rebuild is the ticket. Hope he has money for it.

I don't understand it either but i have seen head bolts bubble/release pressure like that, wild.

The inside of that engine looks like the inside of a fire truck's pump. Nasty muddy scale everywhere. My opinion is that a previous owner didn't wanna fix his coolant leaks and kept adding tap water to the engine. Perhaps a bunch of stop leak too. I suspect this engine has been neglected for a very long time. A real shame the owner got shafted pretty hard on this truck, I hope it was cheap.

What a cliff hanger!

A lot of problems...A testament to Cat that thing even starts up and runs. Hope we get to see it rebuilt...but I doubt it, probably got a "Deal" on it.

Looks like a coolant sealer was used on it at one time. heavy coating on everything.

Love your videos💙💙💙. Can you please do a video on the CAT 3408 series. Thank you.

Wanderlodge/throwaways, I represent that remark.

Saw that yrs ago on a guys fleet of trucks with cat c15s, the trucks were ordered with now water filters, the guy didn't know, never dip checked coolant to test it, ate his liners away, id say trucks were 8-10yrs old at the time

Looks like it’s time for a new cooling system and a full engine rebuild and while you’re at might as well go through the whole drivetrain too

Always very interesting thanks for sharing Josh 🦘👍

It reminds me of the GM Delo antifreeze, GM's answer, antifreeze not changed at recommended intervals. Mechanics called it " Mississippi Mud" From my Cat years, never saw it with Cat Long Life Antifreeze.

i will say this, i had an issue with a kubota transmission constantly blowing out an oring. talked with them and they said it was somewhat of an issue and the current fix was to install a new oring, then put silicone. i asked why they even put an oring there when everything else on the dam transmission was put together with silicone and the guy said, i dont know, engineers do what they do lmao. also it looks like the previous operator had a bad coolant leak in a mud park and fixed it but only had the muddy water to run it lmao