Best Engines: GM Builds an Awesome V12 with Detroit Diesel's 12V71 "Buzzin' Dozen"

Learn more about this sweet 12-cylinder engine from Detroit Diesel, the 12V71.

[@tonyelliott7734]

Twin 12 V 71s at max rpms in an offshore yacht is a mechanical symphony that everyone should experience at least once before they die.

[@chrisadkins6830]

Sorry friend but what you said is both true and wrong at the same time. Symphony vs sympathy. Hahahaha.

[@tonyelliott7734]

@@chrisadkins6830 Damn. A combination of spell check and not proof reading before posting strikes again...lol 😆

[@chrisadkins6830]

@@tonyelliott7734 hey, made it even better. The vids of the destruction runs on these screaming Jimmys are awesome. Very few things sound as beautiful as one about to blow

[@tonyelliott7734]

@@chrisadkins6830 DeBoss garage...lol

[@bradchll]

I still see the odd DD 12V71 around, but always in old logging and mining equipment. Forgetting for a moment how visceral these things sound, the 71 series, I believe , were frankly one of the toughest diesels, especially in the worst of conditions . They happily ran continuously at higher rpm . They were a joy to shift in a truck and you had to be fully “on deck” to operate, to be rewarded with quick shifts. Again , hauling off-road in mud a new four stroke would be stuck in one gear until you hit a downhill.

[@kimmer6]

I was a Field Engineer for General Electric Company in the 1970's and 1980's. We saw lots of these twin turbo Detroit V12-71's on gas turbine generator sets. These were mounted in the Accessory Cab at the front of the gas turbine and ran through an Accessory Gearbox. The Detroit Diesels were STARTER MOTORS for frame 5 and Frame 6 gas turbine generators, 24 megawatt and 34 megawatt units. These units were often ''Peakers'' where the utility company needed another 100 megawatts very soon. Start up 4 GE Frame 5's and within 15 minutes they could go from cold to full load, run for several hours or days, then shut down and be on standby. Some refineries and power stations ran them for months on end. They sure drank fuel oil or burned huge amounts of natural gas. The V12-71's were coupled to a Twin Disk torque converter and had a one way jaw clutch to spin up the gas turbine to 20% speed (about 1000 rpm) where fuel was introduced and the spark plugs were firing. When the turbine combustion system lit off, the Detroit Diesel would scream its guts out and assist the turbine to spin up through its rpm range. The turbine would overpower the jaw clutch at some point, maybe 70% speed, and run up to 5100 rpm running speed. Sensors would idle the Detroit for a few minutes in cool down mode then shut it off. Those Detroits had a harsh life. When the turbine start signal switch was turned, the Detroit fired up and idled for about 15 seconds, then would go wide open governor for the next 5-7 minutes. There was no muffler, just a straight stack out of the roof of the Accessory Cab. After about 10 minutes, the Detroit shut down until the next time the operator called for a turbine start. These things were LOUD! I recall that they were rated 600 horsepower as shown on a tag on the diesel.

[@MUUKOW3]

There is a video on KZbin of one these plants firing up. Just amazing sounds!

[@bradchll]

It’s always amazed me that the 53 series, 71 series were used in the most unforgiving circumstances and gave a long life. 92 series not so much but they were dragging a lot of horsepower out of a smaller engine, compared with both Cat and Cummins. For sheer toughness they were hard to beat. We still have some in use powering HD Hayes and Pacific off road logging and equipment haulers ( all museum pieces now) in BC.

[@kimmer6]

@@bradchll I have a nice 3-53 in my shop. Maybe....this year I will trailer mount it, install a seat and a right angle gearbox, and make it the world's noisiest Margarita Mixer.

[@bradchll]

On your idea of the margarita machine using a screaming lil 53 series, fantastic idea! I want to see and hear it if it gets built. Think of it as a mariachi band for gear heads while you sip. I think Jimmy Buffet would be grinning as he was a gear head also.

[@kimmer6]

@@bradchll I'll be the operator and taste tester. You bring the limes.

[@92nbush]

Theres an old trucker saying if you're driving a 2 stroke, there's only one way to drive them. First you gotta take your hand and slam in the door jam first thing in the morning, then spill about a half a pot of coffee in your lap so you know you are good and pissed off and keep the petal to the metal for the rest of the day. The reason is that the detroit 2 strokes hate being lugged down and often will cause premature mechanical wear and failure if you drive to gently.

[@philstarsick82]

Amen brother!

[@keithwood4297]

That’s the way we were taught! Let it scream, they love it

[@AlanRoehrich9651]

You don't have to do that with a 12V71T. It has plenty of power. That saying was created by guys who drove naturally aspirated 6V71 engines in fleet trucks.

[@wildcoyote34]

@@AlanRoehrich9651 i remember a guy i used to work with at the rock quarry near where i live ,,guy was used to driving a dumptruck that had an old 1693 caterpillar , the truck i ran every day was a 359 pete that had a 12V71 ,and i remember having that poor guy about shit in his pants when he rode with me cause he swore iwas gonna blow up the engine ,,causei drove it with my right foot on the floorboard ,, that stupid CAT you were looking for the next gear at 1700 RPM ,, that ol Detroit wasn't even getting warm yet at 1700 ,,,dude's eyes about rolled up watching the tachometer getting up towards 2300 before i shifted gears ,,and that old pete had a 6+4 spicer twin stick ,climbing up out of the quarry was a 23 percent grade meaning LOW gear , let er sing ,,the truck he drove would get hot and boil over if you tried what i did all the time with the detroit ,,best thing that ever happened was the day jimmy tried to drive that CAT like my Detroit ,, idon't remember what the boss said but i do remember how mad he was ,,,something about cats not being driven like that ,,and then there was the 1693 that suddenly had several observation windows in the engine block after an incident involving a missed gear going down the 23 percent grade into the pit ,,he tried the same shit i did every day with that buzzin dozen

[@paulkimber6028]

Yep, that's what I was told.. Slam your thumb in the door and drive like you're trying to blow the fucking thing up.

[@bobsmith2637]

Detroit was the last of GM's big three diesel divisions, coming after Winton/Cleveland and Electro-Motive. I'm a railroader so I'm most familiar with the three series of EMD engines, the 567, 645 and 710 (those numbers are also displacement per cylinder). The 567 is exactly twice the bore and twice the stroke of a 71, and was designed at the same time by the same GM engineering team. The main differences from Detroits are that EMDs have a fabricated (welded) crankcase and top deck (these two sections are bolted together and constitute the 'engine block'), they have individual heads and single cylinders (power assemblies) can be removed and replaced fairly easily. They are overhead cam engines with no pushrods and turbocharged EMDs do not have roots blowers, instead the turbo has an overrunning or 'Sprague' clutch and is kept spinning by the engine geartrain when idling or at lower speeds. As the engine revs up the 'load' of forcing air into the engine gradually shifts from the geartrain to the exhaust turbine, and the clutch disengages once there is enough exhaust pressure for the turbo to freewheel faster than the gears are turning. EMD has used this turbo design since the late 1950s, and it might be the earliest example of what would now be called twincharging. EMDs are all 45 degree V engines, with power outputs ranging from the 600 HP roots-blown 6-567 all the way up to the 5500 HP turbocharged 20-710. The 567 is a legend in the railroad world, as it more than anything else is what killed the steam locomotive in North America. And they all have that signature 2-stroke scream on steroids, the earlier turbocharged 567s and 645s without exhaust silencers are my favourite, they shriek like a banshee, no diesel rattle at all, they sound like a bass-boosted jet engine on takeoff. EMD is now owned by Caterpillar and the 710 engine is still in new production today. It gained electronic injection and controls in the mid-1990s (the computer in our locomotives is called the EMDEC, their version of DDEC), and can be found in locomotives, ships and generators all over the world. Dual-fuel natural gas versions are available and it even meets the EPA's Tier-IV emissions standards with exhaust aftertreatment, though the railroads are avoiding these systems like the plague and as a result very few new EMD locomotives have been built for North American use since Tier-IV came into effect (rebuilds are grandfathered in, and there are thousands of older EMDs still running in daily service in North America alone).

[@JAMESWUERTELE]

I used to work on 645’s for power generation. 2.5 mw a piece.

[@fitzmorrispr]

Makes me wonder if EMD’s tier IV efforts could be translated to the DD platform, as i recall there’s still new blocks available from the company that bought all of DD’s 2 stroke tooling…

[@FlatBroke612]

Nice. I was engineer on a tug with two 645 mains and a couple 8-71 aux engines. Absolute music at full away! I also saw the aftermath of a 12v149 which ran away, it destroyed the alternator and even threw the pole shoes off, it finally stopped after damaging the valve train enough but surprisingly the rotating assembly stayed together. They’re great engines, I have a few 6v53’s in personal projects. One is likely the only Detroit diesel powered 1924 Fordson F model tractor in existence. That was a fun build.

[@jamescaliendo1030]

Thank you for this. As a truck driver here in NYC, and also a rail fan I found your post extremely informative and interesting

[@skipnick]

i never got to run the FL-9 :( i just missed it by 2 years

[@retireditguy9493]

I was in the Navy on the rivers in Vietnam and the Detroit 71 sound is iconic to me as that of the Huey helicopter. I was assigned to ASPBs (Assault Support Patrol Boats) that had 2 12-71s. PBRs on the rivers had 2 6-71s and some of the troop carrying boats also had 6-71s.

[@MUUKOW3]

Well first thankyou for your service and sharing a local mill had bought one of surplus and used it for a log pusher in the ponds .That thing sounded awesome off in the night.

[@zubrickadvisors6742]

Yes I was aboard and LKA and we carried 8 "Mike" boats, or landing craft. The 4 large Mikes had 2 12V-71's. I was a boat officer and the guys used to get pissed at me for taking over and revving those babies to max rpm. But the engineers loved it.

[@michaelhatcher5264]

Detroit Diesel also made a 6-53 V six cilender the Army 🪖 had these in the M- 113 Battle Taxi.

[@donaldreadenour3776]

Back in the early '80s, I was a mechanic in a mechanized infantry unit in the U.S. Army in Bamberg, Germany. I was the operator of a M578 Recovery Vehicle (VTR, or a wrecker on tracks weighing 30 tons) which was powered by an 8V71T Detroit and our battalion consisted mainly of APCs (Armored Personnel Carriers) powered by 6V53 Detroits (318 Detroit) and I still have flashbacks to arctic cold mornings before the sun even came up when we would have training alerts and ALL the equipment must be ready to roll out, the smoky haze over the motor pool, the distinctive smell of 2 stroke diesel exhaust in the air, and the roaring thunder which was comprised of the hum of the dozens of the 318 Detroits idling, warming up, and waiting to defend our way of life. Throw in a few Continental V12 air cooled diesels in the 60 ton recovery vehicles (M80s), the straight 6 multifuel "Deuce-and-a-halves", and the 250 HP "Big Block" Cummins in our 5 ton trucks, GOSH!!! I've been out of the service for decades now, but every time I smell diesel fuel, diesel exhaust, or hear the melodic hum of a Detroit Diesel engine, I am compelled to put my hand over my heart and hum "The Star Spangled Banner" no matter who thinks I am a nut!!! ...and to top it off, I'm a Ford guy, but the ol' 2 stroke diesels have a mighty special place in my heart!!!

[@daledavies2334]

Yup the 6v53 is 318 CID. But the 318 generally referred to the 8V71 truck engines which happened to be 318HP. These were naturally aspirated, no turbocharger. The blowers were there for scavenging, not supercharging.

[@josephrodwell6643]

Exactly , I was in Germany (Fulda Gap) . I remember that smell

[@bradchll]

In mountainous conditions, logging, especially to be able to shift quickly off a landing, the V-12 was unmatched. Torque at idle was the highest, even amongst much bigger engines, K model Cummins, 3408 Cat. Clark trucking in British Columbia had a fleet of V-12’s hauling refrigerated goods in those mountains. Horrible fuel mileage and constantly in need of topping up the oil was a down side, but my gawd did it ever sound fantastic pulling hard. Very, very effective jake brake as well.

[@MUUKOW3]

Had a friend that was a mechanic for a logging outfit that ran those. Went on a late night "test drive" bobtail. Windows down foot the floor never forget that sound.

[@mainebigfoothunter7088]

I've operated lots of railroad equipment with 4-53 and 3-53 Detroits. As a kid before the interstate came along, I got to hear Detroit powered trucks travel by Dad's farm

[@gcrauwels941]

The -53s have a distinctive sound thanks to the straight lobed blowers.

[@michaelsullivan2361]

I operated a Euclid TS-24 scraper back in the 80’s. 12V-71 in front and a 6-71 in back. Both with straight pipes! Nice machine and pretty fast, around 35 mph on the haul road. But LOUD!!! First time I ever wore earplugs on a scraper. Prior to that, I’d been running Cat 641’s & 631’s. I did like the sound of those two Detroits singing in harmony, however! Back in the 40’s, 50’s & 60’s GM was at the pinnacle of engineering prowess. Nothing was too big for them to take on and excel at. EMD Detroit Diesel GM Coach Euclid Allison They led the world in design and innovation!

[@yunoguy2498]

Another cool thing about the 2 stroke Detroit units is they are modular so a 12- 71 is basically two 6-71 heads on a shared block and you can use one 8-71 head on a 4-71, all the pistons and liners are interchangeable between the different configurations of the same series and you can even reverse the direction of the head on the inline motors and the block has provisions to swap the cam to the other side so you can have the exhaust side of the head pointing to the left or right. They are overall very well thought out and straight forward to work on and it's a shame more things can't be designed that way today.

[@keithkauffmann5815]

Adam, great videos on the Detroit Diesel motors. My dad worked at DD for 26 years. As a kid, the engine that blew my mind was the 16V149. Basically 2 V8s bolted together with 149 cubic inches per cylinder. If I remember correctly, I think the engine weighed about 10,000 lbs! What an absolute powerhouse.

[@leonardhirtle3645]

I rebuilt several 16v149’s in my marine career. They were an amazing engine. They produced about 1000 hp naturally aspirated. As you said they were 2 v8s bolted together an we had to separate the two blocks to replace seals . This was accomplished by standing them on end in the engine room using large chain falls.

[@rf159a]

I think I installed a couple of emergency generators that had this engine. The start-up guy said these were some of the best diesels made at the time. This of course was many moons ago. I was an electrician for over 40 years!

[@joesutherland225]

Yup usually had ge gear on electrical side not always though as you could order any prime mover you wanted on all of them.

[@michaelsullivan2361]

I had a job testing standby generators. At one hospital, they had a bank with 2 Cummins powered and one Detroit. One of my tests was to see how fast they would come on line after interruption of commercial power. The 12V-72 ALWAYS won! The two Cummins would just be firing and the Detroit was screaming away at rated power. It was almost instantaneous!

[@MUUKOW3]

​@@michaelsullivan2361The only one close was the Scania 12

[@gregculverwell]

While a long piston skirt is good for piston stability, in this case it was necessary because the piston acted as a spool valve. It had to keep the ports covered when the piston was at the top of stroke. Otherwise the air from the blower would escape into the crankcase. The long piston did make the block taller (and heavier) than otherwise would be necessary.

[@edwardpate6128]

As a teenager in the mid 70's I worked at a service station(Remember those?) in the suburbs of Detroit. A regular customer almost daily was a guy with an early 60's GMC with a 3 yard dump body on it and a 6-71 engine. He would fill up on diesel and buy a gallon of oil and pour into the engine and then would go roaring off, that engine screaming like crazy! I always heard them referred to as screamin demons back then.

[@1Dougloid]

I worked at McDonnell Douglas in the 80s and on the flight line they had two compressors for pressurization checks on the MD11. One was what they called the huffer truck, had two 8v71s back to back and the other was powered by a 12V71. It sounded glorious running at full tilt.

[@paulkirkland1535]

I grew up around Detroit diesels in the '70's. Oh yeah I remember the "buzzing dozen" in GM heavy duty trucks with 15 speed gearboxes. Certainly brings back memories, I'll never forget the good old days. Great video.

[@domenickblancato8600]

I was raised on Detroit engines. And I still love them.

[@thundermite1241]

Lets not forget the 8v92ta that was featured in the m1070 tank hauler

[@keithbrown3704]

I did my apprenticeship with International Harvesters so as a result came into contact with a significant number of Detroit's of various ages from 53 series then much later 92. They struck me as being a well designed and thought out engine finely built components compared to some of the others at that time. There were continuous improvements over the years, including the introduction of the cross head piston, or more commonly called the articulated pistons. I don't recall any other manufacturer employing this system until years later, also above port cooling. These engines have a small rectangular air box cover rather than the big single oval one, aluminum rocker covers bigger injectors etc to name just a few. The oldest Detroit I rebuilt was, I think from memory was called Grey Marine, I may be wrong here but it was x military 6-71 low block, it was powering a small tug boat and reportedly came out of a US landing craft. Obviously a lot of the manufacturing techniques used in this particular engine were of the period, of note was the use of a one piece conventional head gasket rather than the later compression seal ring configuration. I have no idea how many hours the engine had done over all, and there was no indication it had any significant prior work but after the rebuild. liner kits, valves, injectors, bearings, seal and blower bearings, oil pump clean and inspection etc all the normal things, no crank regrinding or anything of that nature it went back into service. Ten year later when I left the area it was still going strong up to 15 hrs a day dragging all types of barges around. My thoughts on the Detroit. I think it was one of the most outstanding engines of its time, yeah it leaked oil and had its flaws, what engine is perfect. but it was honest, worked hard. Because or standardization of parts across a series it was cheep to rebuild and relatively simple in the process. the only service tools required were the injector timing gauges, you could do the rest with a basic tool kit I remember reading in the early 90s that something in the order of 85% or more of Detroit's built were still operating in a multitude of applications. If that's not testament to a good engine design, what is?

[@ElvinLeadfoot]

1979 Long Hood Kenworth 12V71 twin turbochargers Ed Davis A treat for everyone to see :)

[@danflemmer1999]

Buzzin' duzzen ferever!!!! Love that sound. A pair of 4-71's in a terex scraper ain't too shabby either.

[@ricksmith4736]

Ol2stroker has two V12 trucks in his collection... He just pulled one to rebuild... Good show..

[@ericwhitehead6451]

When I was in the Air Force in the early 90's, I remember the tugs used to pull C-5's and C-141's around used turbo charged V12's. Great sounding engines.

[@iceman45ification1]

I miss the sound of those old Detroit 2 strokes. Best sounding diesels ever made. 👌 The reason the pistons were so big was that they needed to seal off the lower liner ports while the piston was in upward motion and also the reason they had rings on the bottom. Otherwise, the pressure would leak into the crankcase and create all sorts of problems. Nice video, my friend. 💪🔥

[@Colorado_Native]

One small correction. Noise is unwanted sound. These make joyful music. Enjoyed the video. Thanks.

[@alangarton4313]

I drove and worked on the 6-71 in school buses for a dozen years in the 1980's. They not only were a great, long lasting, and powerful engine for a school bus, but they were a lot more forgiving to inexperienced drivers then, say, a 743 or 855 Cummins. We had a couple of the turbocharged engines in the buses, making 250hp, and with a 10 speed trans, it would move right along in the Sierra-Nevada mountains.

[@williamtoy3704]

855NT. One of my favorites.

[@LBrawn]

how are they more forgiving?

[@michaelsullivan2361]

Crown?

[@L-Taraval]

A few years ago, I had the opportunity to purchase a few Crown school buses that operated in the Sierra Nevadas. I forget what district, but I went to inspect them and was just amazed that they had 6-71 turbos with Jake's, 10-speed roadrangers, and Traction sanders, among other things. All started and ran beautifully, but I didn't bid. I'm still kicking myself for not purchasing one of those gems

[@chrisberti3794]

I sailed on a ship that was built in the 60's. Used Detroits for everything besides propulsion. Two 12V149s for back up generators when we had no steam. They were so loud that when they were running you could hear them across town from the harbour. If they were both running and you were down checking them out standing on the cat walk between them would make your eyes vibrate and your teeth chatter. We also had two 12V92TAs as back up fire pumps in case we had no electricity. I and about 240 others owe our lives to those engines as they ran in a smoke filled space for days as we fought an incredibly large engine room fire. And lastly we had "the green leakers" two 6-71s in our landing craft. Made a lot of noise to barely get the landing craft moving, and were more likely to overheat than actually land anything anywhere. I loved working on those engines, reliable right until the day the ship went to the big razor factory in the sky.

[@robmikell7444]

Hello there friend. I'm a retired heavy equipment mechanic. I've rebuilt a lot of Detroits. When I was a novice I saw a fresh 4-53 run away on startup. I was always extremely cautious around these noisy beasts. To the uninitiated, a Detroit sounds like it's going to blow up. Being 2 cycle, it revs twice as fast. And that smell. Like following a Greyhound bus ( also Detroit). I had a healthy respect for them. We had a 1 foot square board with a mop handle. The blower shutdown ALWAYS comes off on rebuild.. They were there for a reason. Runaways.

[@DeweyBlanton-ku7db]

Thinking about buying a greyhound with a Detroit. Any thoughts on what to modify first?

[@RandThompson-dd3sk]

Yup. When they runaway everybody runs away too. Once I was running a Gradall that ran away. Gritting my teeth hoping it didn't granade in my face as I was weaving thru hydraulic hoses and cylinders getting to the flapper. It's a sound and experience one never forgets.

[@buick1955]

A Screaming Jimmy. One of the best videos on KZbin , The Big Blue Guck - Driving to Work. 1963 GMC Crackerbox, running a Detroit Diesel 6-71 2 cycle engine.

[@hughjass1044]

I commend you wholeheartedly for your accurate description of how these engines work and for NOT calling those blowers superchargers which they are not when they are used on these applications. This is one of the most common mistakes that car guys make because they are used to seeing them only on hot rods, hemis, top fuel dragsters and the like where they are in fact, superchargers in those cases. You really need to have had exposure to trucking, diesel mechanics or some related field to understand the difference. Bravo!

[@jdcole333]

I could be wrong but I think the first roots type super chargers were scavenged from DD's. Early on they were all classified as either 6-71 or 8-71 blowers.

[@WhiteTrashMotorsports]

Thank you, I cringe when some dolt calls a turbo. Detroit twin charged because of the blower.

[@johneckert1365]

​@@WhiteTrashMotorsports#ME TOO

[@hughjass1044]

You are in fact, absolutely correct. That's exactly where they came from and it was down to nothing more than availability. The 71 and later 53 series Detroit Diesels were in widespread use in those days and the blowers off of them were plentiful as a result and relatively cheap. Another common misconception is that the 6-71 blower gained such wide favorability for use on Mopar hemi engines because it was engineered to work on a 426 CI engine which the 6-71 Detroit is. This is wrong however as those engines had been around since the late 30s and the 426 Hemi never arrived until the early 60s. It was simply a coincidence and a case of those being very common engines in those days; I myself operated several of them in my early days, and availability was high. @@jdcole333

[@DS75921]

Never drove a truck with a buzzing dozen but drove a 8-V71 and it was pure music to the ears.

[@ferragus00]

My father repaired those engines all his life. I grew up with those wonderful sounds. I believe they were generated by the blower with its elecoidal rotors made of aluminum. Wonderful engine. Special mention to the direct cylinder injection system.

[@pcno2832]

Thanks for posting this. I didn't even know that 2 stroke diesels existed in more than theory until your last 2 videos. PS: If you haven't already, you might consider doing a "worst transmissions" video on the Chrysler Ultradrive 4-speed automatic. I had one rebuilt at 30,000 miles, just after the first fluid change, about 25 years ago, and had friends who went through the same thing all through the 1990s. Then, just recently, I read that it was not really the transmissions themselves that caused most of the trouble, it was dealers putting Dexron in them, and that some of the "failed" ones would magically come back to life after Chrysler's fluid was installed. It's a bizarre story considering the fact that Chrysler was rebuilding these things while both the owner's manuals and dipsticks encouraged the use of Dexron to top off the fluid when Chrysler's fluid was unavailable. If you know anyone who worked for Chrysler on the problem, it would make for an interesting interview.

[@gcrauwels941]

These are the engines that powered many of the yachts and work boats I worked on. The JT6-71TAB (Johnson and Towers marine) produced 485 hp and was pretty much the limit for the 6. We had car ferrys with a pair in 12V71Ns (one at each end) that we could inframe overhaul in a weekend. I did get to work on a pair of 24V71Ns (rare) in a research vessel. Setting the racks took patience. They have a sound I miss tremendously. Really heavy components. Hiking a 6-71 cylinder head up the spiral staircase of a Hatteras motoryacht was not easy, even with two guys.

[@stevebyrne4235]

One of fleets I maintained had late '70s GMC Sleepercab Astros with 12-71s, 13 speed, and straight pipes; beautiful exhaust note. 4 MPG; completing a topset (injector height/valve lash/governor and rack) was brutal. We had V12 GMC gas tractors as well, single drive axle with a tag axle for the weight, what fun. Still have my first 60 Series Certificate, framed, a relic, like myself.

[@ericgilhart5951]

Those old two strokes Detroit diesel engines are what made america through so many applications

[@chrisridgeway9790]

The two stroke Detroit ! The most efficient means mankind has ever found for turning fuel into beautiful music !

[@anthonyjackson280]

Harley Shovelhead enters conversation......

[@buckberthod5007]

You're half right. It's the best way to turn money, into fuel, into screaming harmony and smiles

[@halfmil6467]

Author describes it as "turns diesel into noise" Amen 😅

[@kagome122885]

2 stroke Detroit diesels are the best sounding diesel engines

[@joeo5738]

I went to diesel mechanic school in 1980 and my first rebuild was a v8 Detroit diesel. I loved that motor. Sorry that the 2 stroke had to go away.

[@bw6378]

The tall pistons and bottom rings are required to keep blower air from getting into the crankcase. No fuel is in the air charge, that comes from the unit injectors in the head. Also you might mention that the intake air coming in the ports is what pushes the exhaust out through the valves. Also noteworthy is that the connecting rod is always experiencing compression loading unlike a 4 stroke.

[@michaelnault5905]

I rode many Greyhounds as a kid and spent several miles piloting 8V71's as an adult. I'm glad I don't do it anymore, but yes the sound is the music of my youth.

[@geraldo7325]

The skirts are long because the ports are covered when the piston is at TDC, this is to prevent air getting into the crankcase. They also have a set of rings at the bottom of the skirt.

[@Johnnycdrums]

Interesting.

[@johngalt97]

As a gasoline 2-stroke enthusiast, I suspected the skirt as closed-valve, and noticed the bottom ring grooves.

[@robertrishel3685]

The very first inland/rivers towboat I ever worked on was powered by three turbo charged 12v71’s. They were real screamers! We had 6 71’s powering our generators, affectionately known to our crew as the “hammers of hell”. I’m pretty sure there were also a lot of 16cyl Detroit two strokes powering some of the other, larger boats.

[@DanEBoyd]

Ol2Stroker is another great Detroit Diesel channel.

[@frasercrone3838]

Being a little picky here but you said the cylinder ports let fuel and air into the engine but of course it was just air and the injector sprayed the fuel in. The jimmy that made the highest pitched scream was the 53 series and in 6V form it was amazing. It revved higher than the other sized engines which added to the sound but if you put an Allison auto behind it then it stepped up a notch again. I worked for an interstate bus company in Australia during the 1980"s and we had 6V 92T and 8V 92T engines in the fleet with the average distance travelled by each vehicle was 30000 kilometers [18,650 miles] a month. The engines were removed at 1,000,000 Kilometers [620,000 miles] regardless of condition to be rebuilt. in ten years only five engines did not make the mandatory rebuild target. The fleet was around the 150-vehicle mark. What's more is that the rebuilt engines would cover the same distance as the maiden engines.

[@76629online]

Most people could never even conceive of how much freight these engines have hauled throughout history. It's mind-boggling.

[@user-rn2bi6wx2b]

I remember in 1976 the old Greyhound bus they have Detroit diesel they sound good to 🤠...

[@Blazefork]

You'd love the 53 series, they have about 400 more governed rpm....it's beautiful!

[@johneckert1365]

6v53 sounds AMAZING

[@mikebel74]

A mechanical symphony, someone said. Totally agree. Such good memories listening to the ‘buzzin dozen. A sound like no other. Great post!

[@rockymountainjazzfan1822]

A family friend years ago ran a heavy construction and trucking business. All of his big trucks and heavy equipment were 2-cycle Detroit Diesel-powered. The Detroits' only weakness besides noise were those oil leaks--giving them the nickname "Driptroit". He always said that leaving a Detroit idling for any length of time at regular idle was a big factor in causing the engine oil sealing problems. If he was leaving the Detroits idling for any length of time, he would bump the RPM up to about 1,000-1,200. It used more fuel but seemed to avoid a lot of the oil leakage issues.

GM has always been good at producing solid power with multiple cylinder options

[@michiganmotorsports]

I've worked on large stationary generators with 12V71' s. Such an awesome sounding and performing machine.

[@jimkillen1065]

There is a company and i dont remember there name that has some of those engines , they were also turbo charged that powered pumps used to power wash boilers . I believe they were from New Mexico..They came to the power plant i worked at and hydrblasted the boiler .. I dont remember the engines giving any problems while they were there . I remember they were huge. Like a engine you see on a generator set

[@JWZelch]

The buzzin’ dozen!

[@louiskats5116]

Good day Adam, You are a man of my heart, the last thing I was expecting from you was a video on a “ Screaming Jimmy “. Like you I grew up around semi’s & those 8v71 just a sweet sweet diesel to coal music. Still driving semi’s here in Melbourne on & off the wharf & just on Friday a old timer with a 1978 Kenworth Cabover Sleeper painted up in old peaches & cream TNT colours pulls up in the grid next to me in a 8V71 & boy double stacks straight out. I knew what it was but 95% of the newbie drivers wouldn’t have a clue. Next best sound 3408 V8 Cat E9 V8 525 Mack 580 hp V8 Scania 2006 model straight 6 inch pipe 500 hp Mercedes Benz V8 from early 90’s straight pipe 500 hp MAN V10 early 90’s straight pipes. Unfortunately you didn’t get to experience European Cabover V8 & V10 from mid 80’s through the mid 90’s gave the Cat’s, Cummins & Detroit a good run for there money. When I used to sell semi’s for Nissan in the 90’s we sold in limited numbers a V10, 27 litre Nissan Diesel at 420hp. Didn’t sell many just 1 too heavy & thirsty. I hope you know Kenworth has a manufacturing facility here in Bayswater a suburb in Melbourne about a 45 minute drive from my house & yes still manufacturing Cabover. The new K220 Cabover recently got released replacing the K200 from the year 2000. My old boss works as a sales person for Kenworth here in Melbourne and is the number 1 sales person in Australia on & off. Every year without fail since 2009 I receive a limited edition Kenworth calendar & work diary. Saved them all in immaculate condition hope to show you someday when you come to Australia. Cheers Louis Kats your number 1 Fan in Melbourne, Australia 🇦🇺 🇺🇸 👍

[@RareClassicCars]

Thx Louis!

[@vicpetrishak7705]

General Motors Diesel later known as Detroit Diesel . 71 series engines were replaced by the 92 series engines before the series 60 . Also produced were a single cylinder 71 series engine . V-12 series engines used 6 - 71 cylinder heads . Oil leaks were designed . Oil weep tubes draining fly ash contaminated oil from the crankcase while operating . Very much appreciated video !

[@johngalt97]

Hmm, did the bottom rings on the piston have anything to do with that 'fly ash contaminated oil' system?

[@vicpetrishak7705]

@@johngalt97 I do not believe so . The scavenging of air through the combustion may have .

[@tomreisinger6220]

The drain tubes kept the airbox clear of excess oil, not the crankcase.

[@vicpetrishak7705]

@@tomreisinger6220 Sorry, you are correct , I did not state that correctly .

[@evanswinford7165]

We had 8V71s in our WW2 era scout boat. It was an Aviation Vessel Rescue boat used for pickup up downed air crew in the Pacific. During the war era it had the gas Allison V12s which worked good at sea level. Those were removed and we got the 671 inline engine. Those wore out and were replaced by the 8s. They ran flawlessly for many years in the boat and we had to wipe them down after each cruise looking for oil leaks. The engines had been put all the aft after the war era mid engine set up. The boat sat down in the stern and out could see it when we tied up next to other AVRs. Great engines.

[@chrisleggett685]

In the late 90's I was fresh out of truck driving school. I had to ride a Greyhound bus from Hudson Wisconsin to Dallas TX. I was excited to hear the 2 stroke Detroit in that grey hound bus. 24 hrs later I couldn't wait to get off that bus with it's obnoxious engine!

[@RareClassicCars]

I understand both sentiments

[@davidswanson5436]

You surprise me with this knowledge. Thought you were just a car guy. Bravo sir. Gentleman and scholar.

[@joshuadebideen22]

You wouldn't believe how many people think that V6 semi truck engines don't exist😂 The 6V92 is certainly one of the more well-known examples I quite like the way they sound with a single stack

[@LeeLarson-rk6cj]

Hands down, one of the toughest engines ever made 👍🏽

[@johnmaddock256]

I was deck hand on a boat that had twin 12 V 71. We had unlimited power, and the boats top speed was 24 knots full throttle and going down swell but those engines just purred along. The boat was an old Navy coastal boat built in 1943 that was converted to haul materials for the offshore oil rigs but that was almost 40 yrs ago

[@AJISFREAKENAWESOME]

Never been this early to one of these videos. Love this series so much! My generation just doesn’t get presented this information very regularly so it’s really cool to see some of the engines no one talks about!

[@jeanclaude7018]

I have a 6V-71 in a 1960s Freightliner in my barn. Kommunist Kalifornia has made it illegal after I bought it. The "426" of the trucking world. That and the inline 6-71 sound almost the same, and the 12V is like a double-tracked 6V sonically. I rode from Jersey to CA in my father's 1959 GMC with a 6-71 as a boy, and that sound has been stuck in my head for half a century. It used to be heard everywhere, but now is so rare. Eventually the role of the 12V-71 was basically taken over by the 8V-92 T in trucks. I learned to drive on one in my father's Western Star. What a hot rod with a quick shifting 13 speed. With turbo and twin stacks, it was quiet too. It easily kept up with the big cam Cummins of the day. Had to keep an eye on the oil level though. Could burn a gallon a day on really hard days of pulling

[@housechadwick7505]

Everyone loves the way they sound in short bursts, get back to me after 16 hours straight in an old International cabover. The wah wah wah wah of it bouncing off the governor, hour after hour after hour. Its how my dad cured me of wanting to be a trucker 😂 I miss th old man.

[@AJmx2702001]

Detroit 2 strokes were a decent engine and probably the most adapted to any applications around the world more than any other diesel engine of the time which is why I think GM lost the market for heavy trucks from relying on the two strokes for so long

[@61rampy65]

My dad drove a bus (the old GM coaches that date back to the 40's) back around 1960, and I sometimes rode a bus to school in 1970, and I loved the sounds of the 6-71! Still do. As much as I liked your sound effects in the last few videos, thank you for putting in a clip of a real V-12 Detroit Diesel! And yes, it did sound like it was turning about 6000 rpm (even tho it wasn't). Cool video, Adam!

[@josephdipalma5989]

Awesome video, I started my career as a Union Carhauler in 1988 driving a 1979 GMC Brigidier. It had a 6-71. Awesome sound, but no power to match. It was still a fun truck to drive. We changed to Volvo/GMC's with series 60's in the 90's. What a difference. It's amazing those early Detroits were relevant for over 50 years. Most buses in the NYC area had them also.

[@MitzvosGolem1]

Do a show on Charles Kettering and the Zephyr Diesel electric train where these began. These two strokes were good but could not pass emissions. They made a 53,71,92,110,149 in V and straight . Even doubled Siamese in large gensets . Excellent channel.

[@Tchristman100]

Don't forget the valve less series 51 in 2 and 4 cylinder.

[@MitzvosGolem1]

@@Tchristman100 oh yeah never saw one Thanks

[@turbo8454]

I still get my Detroit two stroke fix. I have four of them.

[@terrystewart2070]

Great video with only a small correction: The ports only induct the air, the fuel is injected by a cam/rocker arm actuation at the top in between the exhaust valves, which are also cam/pushrod/rocker arm actuated. Bus Grease Monkey is a great channel to learn all about DD, as is The Ol' 2 Stroker KZbin channel.

[@I-Libertine]

Thank you for your channel. It is very interesting and calming, too. Much appreciated.

[@ShadowOppsRC]

Got to love that 2 stroke diesel scream! Thanks for sharing!

[@myronfrobisher]

Excellent Adam , well done !!!

[@tomromanski7925]

It's nice to see you're delving into some cool diesel history. I'm a farmer and run trucks as well. Growing up the 2 stroke detroit was the choice of power for most of the irrigation wells, and alot are still currently in use today. I also still have 2 trucks, one with an 8v92 and one with 6v92 still running strong. There's nothing like that sound, and I couldn't imagine a world without it! On a side note, have you ever heard of the International Harvester UD series diesel engines? They were early diesels that started on gasoline and then there was a compression lever you pulled to switch it to run on diesel. We have some of those too. That could be a fun topic to research.

[@mikevan5219]

We have a Detroit 71 it's retired mainly but it gets busy around the soybean and corn harvest. Its well maintained and it served us well at the CO op. Its previous life was a hauler kid you not it got 4 million miles on it.

[@erwinzeeland9390]

I'm currently still working with Detroit diesels in the Netherlands. We have one 12V71 as emergency generator and two 16V71's as firefighting engines. For those purposes the best choice, they only stop when the last connectingrod pops out of the block.

[@jazzfan6]

The engine does have a distinctive and pleasing sound -- it sounds 'healthy' and eager to run.

[@anthonyjackson280]

The Commer TS3 (The Knocker) from UK also had a very distinctive sound. 3 cylinder opposed piston 2 stroke Diesel.

[@lubesiron-cslfarmsllc2751]

Now that youve covered Detroit Diesels, you may want to consider doing a video on the GMC 4 stroke Toro-Flow V6 diesels.

[@gabrielv.4358]

Really legendary! I wish Detroit made a 1.5L 4 cylinder engine for cars, it would sound SO awesome

[@georgewilson1184]

I drove 671s in GMC 9500 Brigadiers and Ford 9000s we called them old Sing a Songs the 12 71 was a choir LOL that thing would really get you up & going running Line haul at 4:00 am in the morning

[@DanT271]

Love those old Detroit's nothing compares with the sound! I always rode transit busses as a kid and the drivers were always brutal on the throttle and I loved the sound and black smoke I am also subbed to Scott over at BGM and Ol two stroker

[@phil955i]

Very informative video but it was only air that was pushed into the cylinder with the blower, the fuel was injected at the top of the piston stroke, initiating combustion. There is also an exhaust valve in the combustion chamber, operated by a camshaft, that opens at the bottom of the piston stroke. The incoming air forces out the spent exhaust gases through the exhaust valve.

[@user-xy1lp8jx2h]

I love the sound that those detroit diesels make. Back in the 1970's a construction company in my area had a fleet of Chevy medium duty dump trucks , C60 or C70 's. They were powered by 6V71 detroits. Loved the way they sounded.

[@tonyx3768]

Fuel is injected like with other diesels, only air is blown in through the liners. That said, I love the stories about wide eyed drivers almost stalling one and it kicks over and runs backwards. We have an Oliver Super 99 with the 3-71, the timing is quite advanced. It happened to my brother at the end of the pulling track once. It was a real oh sht moment when it started backing into the sled with smoke pouring out the intakes 😅

[@zacb7427]

Not possible the DD fuel pumps only operated in one direction it runs with the blowers and the governor.

[@tonyx3768]

@zacb7427 Maybe learn about how things work before you make yourself look stupid interrupting the adult conversation.

[@jamesbell6182]

A look at the 12v149 would be great, they have a lot of features that were shared with RR Merlin the big one is the bladed and fork rods. I remember all of those autos from the past . Good stuff

[@russvoight1167]

Very good presentation

[@coburnlowman]

I absolutely loved driving up Mount Eagle at night with the windows down. That sound bouncing off the rock back into the cab. Awesome music. Tho I was sitting behind a 6-71. Those things shifted so smoothly. Or the way they dereved and accelerated, made them shift like stirring a pot of gravy.

[@Dr_Reason]

Ready for the Monfort lane.

[@ScottAbgekurtz]

The US military still uses Detroit's in a lot of applications, most notably the 6V-53 in the M113 Armored Personell Carrier and many marine applications. Although I'm not a big fan of the noise that these engines make if I had a favorite it'd be the 92 and 149 series, those do make a nice noise. You should make a video on the big brother of the Detroit Diesels, EMD Diesels. EMD's make a really nice noise particularly under extreme loads.

[@johneckert1365]

The reason the military uses them is because they're 100% mechanical and require zero electronics to run (other than starting). Makes them immune to a Magnetic Impulse bomb. Also no radio interference.

[@jamescaliendo1030]

​@@johneckert1365exactly

[@kevin9c1]

I believe the 12V71 was the largest to be fitted to an over the road vehicle. The 12V92 seems rare and I am not sure that was used in over the road applications. Also, would have been good to mention the DDEC generation toward the end, as they tried to clean up emissions. They definitely were cleaner, but I guess not clean enough. Fully electronic, drive by wire, scan tool, codes, the whole bit.

[@gsm19911]

I’ve driven several of the 92 series in buses. I owned a bus with an 8V92 and since have sold it. First bus I ever drove had a 6V92. Ive only driven a few 71 series but they sound quite similar. The 92’s had more power Ofcoarse and were turbocharged. I miss them. Even the series 60 is getting rare these days, at least in bus form. They were an awesome engine too.

[@warmstrong5612]

Makes a semi-truck sound like a race car. Loved seeing and hearing these things on the road as a kid.

[@kevinvoyer5053]

Yea I had the opportunity to log many many miles on single axle 6/71 powered GMC Cracker Box day cabs, with 10 speed Road Ranger, or tandem Sleeper cab Cracker Box, powered by 12V/71 buzzin dozen, running through a 13 speed. The 6-71 was rated at 237 hp, 610 lb ft tq, the 12V-71 was rated at 420 hp, 960 lbs ft tq, that in each kept you floating through the gears to keep momentum up in hill country, or running flat it at 68-78 mph, sitting right up on top of the front bumper, just inches between your kneecaps and front wall of the cab. Talk about noisy! I remember once the owner added straight dual exhaust pipes on the sleeper, forget about running at idle to sleep in the colder weather! At least they started well on ether. But man running up or down the gears sounded great! Now I’m retired and it’s been over 35 years since then and I’m now suffering with tinnitus and attribute it to the Detroit Diesel’s.

[@paulkelly4731]

Got 2 of them in my boat... wonderful engines

[@SuperDriver379]

There was a few families of these two stroke Detroit Diesels the 71 from 1 cylinder all the way to 24 cylinders, they also had a 53, 92 and 149 cubic inch per cylinder all roughly based on the same ideas, EMD also had two cycle engines but they don’t share anymore than the operation principles. What really did the two stroke Detroit in was mainly the power to weight, they were immensely heavy for their power output, there emissions weren’t the best but it was more of the weight for the power output, beyond the 80’s V engines fell out of favor in heavy trucks do to the cost and complexity and the reason the 6-71’s lasted to the end of time was really their low power output for the mass of everything and if you tried to get 450-500 horsepower out of one you’d start to go down the road of diminishing returns in cost and reliability, it could be done, but not for less than what the series 60 was costing them to develop. A 500 horse 6-71 wouldn’t meet emissions as easily as the computer controlled 4 stroke 60 could. Not to mention the weight of the older design. But I believe MTU is still casting blocks for lower emissions markets and many parts for them are still being produced to this day. They’re not bad engines and there’s still places we’re they have an edge.

[@yvindHvaal]

As a kid I lived next to a pulp factory and they had a couple of Terex loaders that handeled the pulp wood. Both loaders were poison green and their Detroit Diesel engines were singing loudly while working. They woke the whole neighbour hood up early every morning, even sundays! My first experience with Detroit Diesel engines.

[@jimmckinney6715]

Great video that brought back a lot of memories. I've rebuilt everything shown in this video and then some. I used to work in the engine rebuild department at Covington Diesel in Greensboro NC, which was a DD distributor. I'm not sure if they still exist. The 71 series were great engines. It was pretty typical to see them with 300,000+ miles on them.

[@mikewasfaret9563]

I started my trucking career driving a cabover binder with a 8V71 318.

[@stevejarred6484]

May goodness! All this information lately on Detroit Diesel engines from a channel about classic cars and automobiles! Please continue this thread and keep up the good work! I use to work for Lucas Varity Diesel (Later Delphi Diesel) in the Detroit area that re-manufactured Series 60 injectors and fuel pumps and grew to love the sound of their clatter on the test stands ("It was the sound of a hearty paycheck!" you might say... LOL!). It would be an interesting project to adapt one of these types of Detroit Diesel engines to a kit car chassis - It might weigh a ton and slow as a sloth but the sound and torque once you got it going!

[@kjverhage5706]

My family's construction company has a 30 ton P&H crane with a 12V-71 great crane. I've been able to operate it unassisted since I was 8 years old and I'm 34, that machine really teaches you how to communicate, you have to learn to speak up when that buzzin dozen Jimmy is screaming.