The reason most heavier duty diesel engines run a 2 piece piston is 2 fold. The steel top is for heat dissipation and the aluminum skirting is to keep the rotating mass down. Plus if you break a skirt and the block and top is fine you can replace the skirt rings and bearings on the engine and go right back to work. The rods and main bearings are actually considered routine maintenance items and are replaced on a regular basis. That wear sleeve on the main seal is replaced every time you do the main seal on a Cat engine. The bellhousing adapter is to allow it to mate to whatever it is going into they have multiple types for whatever it will be used in. Trucks dozers mine trucks rollers all take a different style.
That is overall a great description. I just have one minor difference in opinion. The steel part of the piston is for heat tolerance during combustion. The aluminum is for heat dissipation and lower reciprocating mass. Rotating mass is actually good in low rpm high torque applications.
You're close, it has to do with heat, but not dissipation. Aluminum is a much better heat conductor than steel, by a factor of 3 or more. Steel has a higher strength than aluminum, especially at modern diesel combustion temperatures, and it has a lower thermal expansion than aluminum, by a factor of 2. So a steel piston top is better because it is better able to withstand the combustion pressure and temperature, while it can get away with smaller piston-to-bore clearance (block and pistons have similar thermal expansion coefficients, if both are steel) which helps lowering emissions. But the skirt doesn't need to transfer much force, it doesn't need as tight clearances as the top and it doesn't get as hot. Steel has about a 3 times higher density, so it makes perfect sense to switch to aluminum for the skirt, it saves on important _reciprocating_ mass (not rotating mass, that's the crank and cam shaft).
@@Hydrazine1000 You're close Alum shirt just guild really. Also most of Diesel engines use full steel piston now since EGR come out in 03 in truck side.
0:23 This sequence was genius. Plus, everyone watching this has had this conversation with themselves about 3 times per project. Awesome content, Eric!
This is the reason I went into heavy duty. Yes the new trucks and some pieces of equipment (skid steers and excavators in my mind are the worst) can be pains, but for the most part you have lots of room
@@speed150mph I came to a similar realization, we try to repair our own tractors usually and it’s great how you just basically have an “engine section” with room on both sides, under, and above… passenger cars are a different world
We used our 3 ton engine hoist to pull the engine out of our 830 case tractor. Theoretically supposed to be robust enough but felt sketchy AF. I had to stand on the back of the hoist to keep the hoist from tipping over and the hoist beam was bending a crazy amount. 😬. Worked though and no one died. Keep these cool vids coming Salvage Adam Sandler.
Unparalleled serviceablilty. Would love to see consumer grade stuff with this level of modularity. Replaceable rear main seal mating surface blew my mind.
Back in the 90’s there was an issue with batches of 3126 blocks. They were listed as “Soft Blocks” and had a factory service letter out that was kept secret from the public. What happened was the casting of blocks got mixed with the wrong ratio of alloys which created a softer metal than standard. They telltale issues started out with the motors blowing smoke and loss of compression. The blocks were breaking down around water jackets and cylinder walls. I had 2 of these blocks in my boat from 1996 and Cat supplied new short blocks around 250 - 300 hours of service. They have the serial numbers of bad batches somewhere on file.
I work for Caterpillar Remanufacturing Facility in Mississippi. I work in Large Engine Disassembly and get to tear down the 16 and 20 cylinder engines. Those take about 16 hours each.
I'm super impressed with this engine...a straightforward design that's easily serviced, uses what appears to be good quality durable parts, and was built to a high standard. If only every engine could be so well-made, we'd all be better off for it
Best damn teardown channel in YT. Brought back memories of dealing with construction equipment in the Army. As seen there, they are dummy proof, lol. You bring out what's most exhausting about them... how heavy everything is. Never saw one tore down below the head and valvetrain, so thanks for that.
The cam, the crank, the wrist pins, piston heads, and the rods, everything about this engine is just HUGE! When compared to a gas engine, at least. Loved this teardown, and your planning montage. Great job Eric, another fantastic video!
Wait until you year one down yourself. You will then really appreciate the size and weight of everything! I'm currently doing an inframe rebuild (wet sleeves Cummins 8.3 6CTA). Nothing is tiny. The injectors look huge until you compare them to the heavy duty engines. Those things are HUGE!
2 suggestions that probably aren't necessary but would seem safer to me - 1) use a jack stand or some other support at the end of the engine when you have something that long and heavy sticking out from the engine stand, and/or 2) always use upward force when breaking bolts so you're not adding strain to the stand. Overall, very cool teardown.
I love big diesels. I have owned many 7.3 and 6.7 fords also 5.9 Cummins. Only once did a 5.9 fail on me. Now I am 70 and due to a total shoulder and knee, I can easily hire the work out. But that CAT of your looks great for the mileage. If possible try to due more diesels, I am not a mechanic but love the things that make motors work.
I have this engine in my 37' RV. Only 60k on the clock. I am amazed at how easily it scoots 25k pounds along, and love listening to the sound of it doing so.
I have a Cat 3208 in mine - pre everything. The 300 HP accelerates the 19,000 pounds just fine. Now if I just had a 6 speed transmission with a retarder I would be in hog heaven. Four speed on the flat no problem but in the mountains the gears are a little too far apart.
Stinky and noisy. I'm not sure why people love em so much. Other than the ability to pull and carry excessive weight adequately. But most people who own a diesel never even needed one. Was just to say "I have a diesel." Lol 😹
I have no experience but it's easy to see why these motors last so long, everything is so heavy duty. Too bad there's always so many negative ppl commenting on these videos. I enjoyed this video a lot. Keep it up.
Eh KT3406E is a bit of a dick. Seeing him intentionally blow several perfectly serviceable 2stroke Detroits up solely for youtube views soured him in my eyes to the point I can't bring myself to click on them.
This is a pretty solid advertisement for that engine stand. I've got a BBC to build and have been looking for one I know can safely bear the weight. They should make them out of wrist pins
77 years old, and I watch a tear down almost every night. Really enjoy them as I only did one rebuild (when I was 16 and we used a tree to hold a block and tackle to pull the 312 out of an old ford). I've driven just about everything I wanted to an Excalibur and an XKE back in the 60s to my current ride in an Equinox with a 1.5 turbo (pig). Keep up the wonderful work you do. The Cat Diesel was amazing and I admire your guts (and good sense) when dealing with a huge 6-cyl. industrial diesel. Stay safe! PS...How about trying an electric?
I worked for a competitor to CAT for 10 yrs. In analyzing their designs, they are always very robust on fasteners both numbers of bolts and size on any given joint. Impressive equipment.
Thank you for being as overly careful as I would be. Thank you for the comedy relief we all need. Just let things fall and run away! I Love Your Channel!
Someone else brought it up, so I will second the motion... Do a 6-71 2 stroke Detroit... not big on power, but have been in use since the mid 30's, and I still love the sound of them... The 71 Series engines went from a 1-71 all the way to a 16V71, and the (71) stands for Cubic Inches per Cilinder... Love the channel, and keep up the Great Work...
God bless Cat! All of their equipment is designed to be rebuilt, from the 797 all the way down to small unit assemblies like the C0.5, all designed by Cat to be completely rebuilt. LOVE EM !
This reminded me of my first engine job in High School. I had to remove 1 big block 402 from my 72 Caprice Couple and only had one tree limb to use on the oak tree in the back yard so I removed both cylinder heads first so as not to break the limb.
Light polish and a hone. New seals, bearings and some cryo headbolts, some CAT yellow paint and you got an engine that will go another 500k miles easy.
thx for the part 2.. it is a beautiful engine design. I cant see enough to call it a loss. I am pretty sure it would have caught a hone, rings, bearings, and repair that injector issue then went 1 million miles after.
I followed this through from part 1 and I have to say this was one of the best engines and teardowns I've ever seen on RU-vid ! This engine is very smartly designed and very well thought out - I would say It's a mechanic's dream to work on one of these great engines... provided it's out of the truck lol - Only Joking ! - Great engine - Awesome video as always - Keep the great teardown videos coming man 10/10
Eric thanks for sharing with us! A lot of people like, and learn from your videos, and it's entertainment, thank you so much for the journeys we take every week. I wish you the best and more!
I love that you're willing to go outside of your experience, and tear down something new and different. Also... no matter how much you complained about how heavy some of those parts were, it sure looked like you handled them better than I would have. No way in he11 am I going to arm-wrestle you. 🙂
Even though I've watching about 30 of your videos, after this one, I finally understand what a 2-bolt and 4-bolt main is. ...yeah, I'm a bit ashamed of myself. 🤣🤣
This tear down really showed the difference between an engine that is expected to do a ton of miles / hours then be rebuilt vs a gasser that is all but disposable now.
Generally, the bigger the engine, the more modular and nicely built it will be. On engines approx double the size of this, pretty much all wear surfaces start to be easily replaceable.
Your gonna get alot of suggestions for more diesel teardown I'm sure, but you need to do a 6-71 Detroit. Designed in the 30s and used for decades. Love the screaming jimmie!
my first truck driving job was for a local steel fabricator, I drove a 1975 GMC Brigadier that had a 6V-92 Detroit. I blame it for at least some of my hearing loss lol
Fantastic video, as always! Now get something really big like a C15 CAT or an ISX Cummins. Fifteen liter monster out of a motorhome or a semi. You think the head bolts on the Mercedes was bad? Crack those loose!
I watch a lot of your videos. I love what you do. This video shows me your very humble. Nobody can know everything, and you even say you don't know what your doing. You still do a great job! Now, you have a beast on your belt! I don't know anything about diesels either, but you now have the experience i would have enjoyed as well. Keep up the great work.
I had a 2005 Kenworth with a Cummins ISX engine. I was driving near Joplin, MO one night and heard a knock in the engine. I shut it down immediately, which ended up being my big mistake. MHC in Joplin tore down the motor and I had broken a wrist pin. I don't know if it was defective or something, but it broke in half. Shutting it down immediately saved the motor, but it was never right after that. I would have been better off if I had just jammed the pedal down and ran it until blew up. It was a company truck so I wouldn't have been out any cash. 😁
Going out of your comfort zone, but you sure made it look easy. It's amazing how indestructible all of those parts look - and quite serviceable (for obvious reasons, haha) too. Loved the planning sequence and thoroughly enjoyed this series.
Very nice, those Pistons just like a Cummins 8.9 but the way those roller followers are mounted is brilliant I bet the only thing wrong with it was the O-ring on that injector. I don't think the bearings were bad enough to make it knock or have low oil pressure. You got a good deal on that one.
@@mann_idonotreadreplies I don't suck at my job, Cummins suck. i t/s and repair more engines, aftertreatment systems, and electrical systems In my life time then you can imagine.
Overall one of the better engine's CAT ever made worked on many of them, only ever seen one seized and the driver was told drive it see if it makes it back and a piston had come apart, the blow by on one of these could be massive and they would still run. good video overall.
Those pistons are articulated pistons Cummins and other engines use something similar. I do know that you were misinformed on the cylinders, the block dose have liners in the block which can be replaced during a rebuild. I was a diesel mechanic for 26 years and I have installed many liners both dry and wet liners, dry liners have to be chilled with dry ice before installation. The counterbore needs to be checked before installing liners. Cheers Glenn P.S.I really enjoy the teardowns.
Accessory Drive, thats where you are at 4:55 this aluminum piece, accessory drive housing, the front is the Acc dr Cover. at 17:43 a piece of rubber hose is good for that, vacuum line fuel line what ever size fits. Main bolts are about 180, head bolts around 320 Lbs in stages, thats what you need a Torque Multiplier for. The outer ring at 25:41 thats a Speedi Sleeve, totally replaceable, front of the crank too maybe. 26:11 the pistons= that's why they Idle So Nice! Soother running engine last longer. CAT!! Either it got tired or "it was just going down the hill and quit running" too much engine retarder Bent Valves everytime. Use a hammer tip the valve stem while still in the head listen for the PoP just like placing your closed hand over an open mouth or the way they pop when lapping them in. As easy as those pistons came out means not much ware, good rebuildable for another couple hundred thousand. All the other this and that, I say Rebuild It with CAT Parts. at 300,000 plus it just got tired, as easy as the pistons came out low on compression if it started especially in the Cold the mains might of even rattled too?? Good Show!!
Here’s a tip for you - and I’ll use the example of when you tried to loosen the first main cap bolt - if you look at the angle you held your breaker bar at, you were putting a LOT more weight onto your engine stand while you were loosening that bolt - VS - if you’d rotated the engine with the crank facing up and then positioned your breaker bar so you were pulling ‘parallel’ to the length (your bar at a 90 deg angle to the crank) of the engine or crank. Hope this makes sense, kind of hard to explain. But the end result is to work with the physics of the whole dynamic, instead of against it. Same thing applies in many different scenarios of when you’re loosening tight fasteners.
These are very service friendly designs. Common wear points can be replaced because the wear points are all sacrificial. The skirts and sleeves are replaceable during a rebuild. Also as stated in another comment, aluminum skirts keep rotating mass weight down and wear will keep things in balance better.
Try using 6"x6"x3' wood cribbing. When I got used to it, I barely use the engine stand. It's super stable and weight doesn't matter. Plus you set it at any height you want to eliminate back strain.
In the fall of 2022 I was considering using cribbing to jack up my semi truck so I could do some work on it. I ended up giving up the ghost because after going up some 38 in, it would just be less expensive and less hassle and less storage space to just get jack stands. Six-by-six cribbing probably could have done the job but then the cost is almost at what jack stands are to go up that height to reach the bottom of the frame-rail. I guess spreadsheet out and everything it was very interesting. Watched fireman train with Caribbean on RU-vid. But if you're only going up 12 to 15 inches or so, 4 x 4 cribbing can easily and affordably do that.
Also The two-piece piston offers several advantages. One important advantage is a lower top land height, thus decreasing the crevice volume, the volume within the room defined by the top land and the cylinder liner, hereby reducing engine emissions. Alot of people think it'd for heat reduction it,s not
Anytime you have a metal tab attached to a bolt, keep your fingers clear!! They have a tendency to stick to the bolt and basically become a blender blade when attached to a power tool.. yeah.
I have a suggestion for an engine teardown: the SISU HD98 inline 7 cylinder, It is installed in Massey Ferguson combines. Thanks to you and Josh, you both have great entertaining channels
Looks like she would be a good candidate for a rebuild. You can still see some yellow deep down! Great vidya as always bud. Josh is THE man. Great cat vidyas. He’s just all-around a diesel genius.
Thanks! One of my favorite teardowns! I think that engine would easily be rebuilt. Not sure what to do about the cylinder wear - I doubt CAT sells oversized pistons for that engine. Maybe bore it out and sleeve it?
Hey Eric, this one was really interesting. I wish gas engines were so easy to service. The parts in this thing were pretty much indestructible but easily replaceable. Very impressive. Cheers!
great videos Eric! I drove OTR trucks for a dozen years, with all different engines. the CAT powered ones (in my experiences) were the best in performance & reliability. the DDs were ok if they were set up right, but I never had a Cumm-apart I didn't hate for some reason or several.
I drove a fuel transport, 9000 gas, the oldest truck in the fleet had that engine. I had a c12, and it was like driving a go cart. Cat engines are the best, to bad they are no longer an option on big trucks anymore. There are plenty on the road, but only older trucks.
Great video! So interesting to see the big stuff. A lot different from my VW Rabbit diesel, except for the wristpins. They were huge, too. OK, not as huge, but still pretty heavy compared to most gas engines.
I welded 2 gussets to my prime engine stand for big block builds, one directly under the top tube that holds the swivel mount, and another at the bottom of the main upright and welded the upright to the base…it doesn’t unbolt anymore, but it is sturdy and doesn’t flex when you rotate a complete big block anymore. Before this, it would flex enough that the paint would crinkle and end up falling off.
How about tearing down a B engine code 5.3L LS? I know that they are different from the z and other engine code 5.3's, but don't know exactly how they are different! Great job tearing down this engine. Really good info on it1 Keep up the good work Eric!
SKF makes replaceable wear sleeves like the one on the crank under the name "SpeediSleeve". They´re usually designed to go on a worn shaft without machining and using a standard seal.
Do yourself a favour, and put a short piece of rubber tubing on the connecting rod studs before pushing them out of the engine. This will prevent any scoring on the journals and cylinders. Excellent work as always, Eric! Also, good to hear that you are becoming more aware of safety as you get older. I was the same when I was younger, and now I try to think of EVERYTHING that could go wrong! Have a great day, Sir! And God Bless! o7
I wouldn't really worry about it on an engine thats getting rebuilt... The liners will be bored and you'd have to have no business working with tools (or engines) if you managed to do that much damage to the cylinder by bumping a rod bolt into it.
@@volvo09 Eric is the first to say that he doesn't know what he is doing. That said, he has been salvaging parts for long enough to know how to save the good stuff. And as a Mechanic of 35+ years, I want to give him tips and tricks to help him on his journey. He expressed concern, I gave an answer. He reads all the comments. And personally, I do worry about the condition of everything when I disassemble it, and when I reassemble it. It's a simple thing to do to prevent damage. Have a great day! o7