spent a lot of time taking care of 6-71s

i got some klotz techniplate synthetic 2 stroke oil to dump in my 8v92 turbo 2 stroke. i like so far and the engine is quite and smoother now but boy its not cheap, bummer.

That 2 atroke 12v71 block out the sun whence it helps with global cooling LOL!

@@jlo13800eat ya heart out greenies 👍🇦🇺

"Combines"

Anyones ears within a hundred-mile radius 🤣

What

Puts some tuned expansion chambers on this 2 stroke, i would love to see that..

The 2 stroke is concentrated energy, like a lightning bolt

@@Leemur2335 they could be driven by a pulsed plasmoid impulse ar explosion using radiant force. Nicola Tesla used violent impulse ar distruptor DC from his arc impulse devices to tap into the aether for radiant force

HELL yeah !!

@@scottcupp8129 Its a 2 stroke

@@scottcupp8129absolutely very deceiving 👍🇦🇺

Well the book was moving slow enough he should have took it home 😂😂😂😂

Actually, they won't run with no scavenging blower. All 2 stroke diesels are like this. Now they are turbocharged with no roots blower. They have no bottom end, so they are run at a high RPM.

@@strobx1 "Now they are turbocharged with no roots blower." Wrong. All DD 2 cycle engines had a blower.

"The v series was turbocharged an supercharged." Nope. DD built 2 stroke V engines with or without a turbo.

i got to got my silver 8v92 out back running.

I’m jelious, I love those 2 stroke Detroit’s. My freight linger has a 60 series.

@@ryanehlis426 i dont like the series 60 4 joke i got a 8v92 silver, yesh the 60 has roller bearings and can be converted to a 2 stroke but i like the original 2 strokes better. Achates power is making a 10.6L 10600 cc op 2 stroke and running a few in a freight liner 579. Also most 4 strokes here have a 2 stroke counter part in the spirit realm!

@@ryanehlis426 the sun is a giant 2 stroke and burns oil at 32;1

@@jlo13800.... I don't know what it is that your "on", but whatever it is... is causing some rather severe hallucinations in your cranium. Just FYI.... the Series 40, 50 and 60 engines CANNOT be "converted to a 2 stroke" in any way, shape or form. The "60 has roller bearings"??!!? You better let the Reliabilt Div. of Detroit Diesel know about that, because they seem to keep forgetting to include them in their rebuild kits for the 50 & 60 Series engines... instead of including upper & lower plain bearings for the rods & mains. Have a nice day. : )

yeah them big 1710 CID v-12 2 strokes, how about a crecy. Unfortunatly about 6 Teska motors could make more power.mart.cummins.com/imagelibrary/data/assetfiles/0058689.pdf

@@jlo13800 what a thing of beauty!!

@@jeffwalker9122 yeah i got an 8v92 and i work on a dive boat, 16v92 for thruster and winch and 200kw 1200 rpm 12v71 480v gens. the 12v71 can go 425 kw with twin turbo at 1800 rpm's. Alco 2 strokes are the mains. the detriots run anti friction bearings. Im running XD-100 in my silver 8v92 turbo, takes about 7 gallons at 48.50 a gallon.

@@jlo13800 That's a hell of a collection! I grew up farming, so I've always loved the big diesels that came with it. Been a butcher now since 1995.

out back i got a silver 8v92 turbo and a 4l johnson v8 2 stroke small block.

Funny note to your story! I work for the man that built this and we are putting the final touches on the new one a 8030 with the twin turbo version of the motor in it. We had it out the other day and I took a video of it and there was a Timber Jack they use to trim the trees on the power lines cumming up the road and you could hear it in the back round. After the owner gets his new toy from us I will post the video I took but I don't feel it's right to post it before he gets it!!

It's also known as the "Buzzin' Dozen" and you can certainly hear it.

@@edwardcalvert Rotax should come out with a v8, v12 and v162 stroke etec engine of about 230 CID per cylnder.I like the rotax 850 etec turbo r in skidoo.

It has a supper charger

@@mikealexander3985 It's a 2 stroke.

@@jimvss no shit

Don't forget the overhead cams for the exhaust valves, the common rail fuel system and direct injection! All the 'new' tech that's going in common cars is actually ~90 - 100 years old. Otto cycle gasoline engines are finally catching up technologically with these old diesels!

BC Logger Well..... your correct on everything, except... if I may, on the "high pressure air"..... it's not, it's "high Volume".... Roots blowers, do Not, and cannot "compress / pressurize / supercharge/ or boost".... air flow, it is... in it's purest form, strictly an "air pump or, air mover"..... no different whatsoever than any common house fan, except that it employs "rotors" rather than "blades" for the sake of making use of tight space, and does so, really well. The "rootes" design comes directly from the "Rootes - Connersville" industrial blowers developed back in 1938 and used, (among other applications) primarily for feeding fresh air into mines... and also for exhausting large volumes of "dirty" air in large industrial applications of the era. The design is excellent for moving large volumes of air, when there is a minimal amount of space available for the blower itself.... and is also (to this day) widely use in supplying air for numerous industrial applications.... it's a very Simple and basically trouble free design, but in and of itself, cannot "supercharge" air flow.... because by design, it is impossible to compress the airflow. Read my reply above, to "Joseph Schewe" on the subject..... if you wish. Have a great day & take care. PS: Are you from "BC" ?? IF so... what part ?

2Stroke Diesel Power This blower type first patented in 1860! One could assume the development preceded this date. No 'E' in Roots BTW :) en.wikipedia.org/wiki/Roots_Blower_Company I believe the Roots design CAN compress air but Detroit Diesel calculated the swept volume of their 2 strokes around the blower displacement and blower RPM rather than vice verse though I could well be wrong about that. Your description re volume is generally very accurate when considering the DD. "In of itself" you're correct they generally can't compress air but in a supercharger application they can and do considering the higher revs petrol engines attain. Also, the clearances are tighter in a supercharger and the blower lobes have seals. Boost pressures are varied by changing the drive ratio of the blower - sometimes 150% crankshaft overdrive, 1:1 or even underdrive. Consider The DD power rating charts: power drops off with elevation increase, temperature increase and a combination of both. The big advantage of the turbocharger is the free spooling (ie independent of crankshaft speed) of the design allows rated horsepower to be maintained at all adiabatic temps and density altitudes (up to about 18000ft). The poor old blower cannot do this because it is geared to the crank so each blower revolution yields a known displacement (usually at a datum of 1013.3hpa @ 15deg C @ sea level) and as the air density changes with pressure height then the amount of air available for pumping gets less so power drops off. Even in a Supercharger application this occurs.

+ThePaulv12 Hi Paul.... Thanks for your reply and correction on the spelling.... it was very late at night when I wrote that... and wasn't completely with it. Actually, my spelling of "Rootes" is correct.... in the sense that I was also thinking of another 2 cycle engine manufacturer in England which use to produce a 2 cycle for Comer "Lorries" (Trucks) and the British spelling was "Rootes" for their blowers. Just mixed them up... anyway, I stand corrected either way. As far as the Roots blowers themselves.... they are, by design... totally incapable of "building boost". What most people confuse with boost when used as "superchargers" on anything from diesels to "Fuel" motors in drag racing.... is NOT "supercharged" or, "boosted" (raised Above atmospheric pressure) air, whatsoever..... what IS happening is a Greater Volume of air is being pushed into the airbox (on a DD) or intake manifold plenum at a greater rate than the engine can injest..... resulting in Backpressure between the valve heads (or cylinder liner ports, in a DD) and the outlet side of the blower in effect raising above atmospheric pressure..... but, again.. the Roots Type Blowers in and of themselves, by design... are totally incapable of producing "boosted" air. There Are blowers produced by certain builders(Kenne Bell, Bendix, and larger Alchy and Fuel motor, blowers) that "look similar" to roots blowers.... but, are not..... and in fact are small Lysholm Screw Blowers..... which ARE capable of... and in fact DO, produce boosted air..... as in, when the air leaves the "exhaust" port end of the housing, it is in fact under pressure or Boosted. Lysham Blowers (Type - not a "brand") consist of two interlocking "rotors" which resemble machine screws... one small, one large which actually takes the injested air flow and compresses it from the "big end" of the housing (intake end) and squeezes it down to a smaller area within the housings exhaust port end, effectively causing greatly increased pressure upon exit.... very similar to what takes place within the confines of the compressor scroll side of a turbocharger. Roots blowers by design, are strictly Air "Movers".... not, "compressors"...... any increase of air pressure when used in conjunction with internal combustion engines of whatever type.... is purely a result of excess air volume resulting in backpressure, showing as "boost".... which is produced with the confines of whatever given engine.... and NOT withing the blower housing, itself. As far as GM Diesel (as it was branded from the beginning) is concerned.... you had the right "formula".... only reversed..... the blower cfm / displacements / rotor speed ratios were calculated around the needs of each engine within it's "family".

Yes, you were referring to the Rootes Group and the Commer Knocker that thermodynamically speaking, was particularly efficient at turning fuel into noise. I am familliar with the Lysholm compressor. Mazda Eunos?? had a Miller Cycle V6 awhile back. The thing with a blower on a Detroit Diesel and GM EMD 2 strokes is the blower is required for scavenging the exhaust from the cylinders. Since all the work in piston engines is done by 90deg crank angle from TDC, the residual combustion pressure is used to begin the exhaust cycle. This goes for 2 and 4 stroke engines BTW. In a 2 stroke Diesel there is insufficient time to clear the cylinder since there is no dedicated exhaust stroke. Also, this 'clearing' must occur in far fewer crankshaft degrees than a 4 stroke motor. This is where the blower really shines. The inertia of exhaust gas flow is begun with the residual combustion pressure combined (of course by the exhaust valves opening). Since the blower is only moving air (as opposed to fuel and air) then the exhaust valves can be held opened until air is actually flowing into the exhaust system. This scavenging by the blower is particularly effective. The cost of blowing air into the exhaust is a pumping loss (loss incurred in the production of power) and is partly the reason 2 strokes are out of fashion currently. The unit injector arrangement of DD 2 strokes is another reason. To get big power big tips are required in the injectors. This means idling and revs below the power band results in high hydrocarbon emissions due to unburnt fuel. DDEC as used in Silver Series (8V92TT) 2 strokes went a fair way to eliminating this problem.

Amen! 2200 and things are getting shaky!

KBS117..... as one who has worked with Detroit Diesel in years past, I can tell you that your power output figures.... are Way Off base. In certain Highly modified (racing) applications, these numbers are attainable.... but in general public use for pleasure craft, etc..... absolutely Not. The Maximum output levels for an 8-92TiB for example, that could be covered under warranty in marine applications is approximately 680 - 720hp while retaining any degree of reliable longevity and overall reliability. There are a couple of noteworthy after-market builders of Detroit Diesel Marine Engines who can custom build Higher Output engines, and have their own limited warrantee's.... however, even their engines Do Not produce the hp outputs that you are claiming that they do. There were several 12-71 Detroit Diesels in the NTPA - Super-Semis Pro Sled pulling class a number of years back that were producing some incredible power levels... but due to a combination of the NTPA's refusal to even out the class and the increasing number of "big money" built, large displacement 4 cycle diesels the V12's slowly disappeared.

@@Romans--bo7br you are Talking land based, epa engines. I'm talking marine and military. Was at the volvo marine dd rebuilder in lake Charles l.a. watched them dyno a military 8v92 with water cooled turbos. It was sitting on 900 horses at 70% throttle. Guy, told me, maxed out it would do 1200 for short periods. He said, the turbo is all that limits horsepower on land based engines. They melt off the manifolds at anything over 700.. water cooled turbos can run much higher h.p. without problems. He also stated they had some military stuff that would do 1400 in short emergency burst for 30 seconds. I laugh at your assumed expert opinion.. they can crank 5000 h.p. out of a cat or Cummins for a tractor pull, but can't do it on this engine? Go back to your coloring book.

@@KBS117..... I'm not about to waste my time quibbling with someone who, apparently does Not know how to read with Understanding, nor with someone who childishly uses insulting phrases such as "Go back to your coloring book." Have a nice life.

@@Romans--bo7br thank you mr. know it all..you are a nuisance..

@@KBS117.... Thanks for your reply, again. With regards to your Original comment.... specifically regarding - "These engines in a boat, produce upwards of 1500 horsepower." The way you worded it, seems to relate to the Series 71, V12... as in the video of this sled puller, correct? IF so... what injectors are being used to attain that much horsepower, and at what engine speed, in the marine applications that are producing upwards of 1500hp? Just an honest question to you.

Deere+DetriotDesiel=💰

Derek VanBrugge I know. (Showing my age) In the late 70s and early 80s I drove a couple of over the road trucks with the 12v71 motor. One was an N model and the other was a TA (turbo and aftercooled.) With the exception of Macks Maxidyne engines, most diesels of that era (Caterpillar, Cummins and the DD) the factory operating RPM range was between 1600-2100 RPM. Since the DD engines didn't produce much torque at lower RPMs (~1600 RPMs) because it is a 2 stroke, it performed much better at higher RPMs (2100 and higher), where it produced the most HP.

i think the 12v71n made 450hp and 1450lb/ft

It has a gear driven roots-type blower. Based on the full pulls, I don't think he needs a turbo?

@@benjamingamble2407 detroits can have turbos added to them and it will add a lot more power. they need the blower just to run

@@benjamingamble2407 they do benefit from a turbo, since the blower only runs at 1-2psi

Yes they do make some noise but the proof of power is evident in the video. Just sayin'.

Buzen Dozen

papabugs71 Good grief.... don't know where folks get some of their "knowledge" from... at least in regards to this "discussion" on DD's. The Blower(s) are NOT... "used for crankcase scavenging ONLY"......... their NOT used for that purpose, whatsoever. They are there for "Cylinder scavenging (partly)" with fresh air.... and when the blower rotors & and case are "in spec" and all is well..... the cylinder air, will enter... under about 4 psi (average).... but only due to "back pressure" as the blower provides more Volume than the engine requires.

2Stroke Diesel Power He might be thinking of the "standard" 2 stroke design where the air first goes into the crank case. I'm not sure that is the case however with all 2 stroke engines including DD's

Agreed. They're great industrial engines, but I've always heard that in a truck, you'd never catch these things on level ground, but they could not pull a hill worth a damn.

Founded 1938

Thats the general story for diesels. Horsepower is a function of torque and RPM. As far as power goes, a 12v71 (14L) will make 450hp and 1300lb ft without a turbo, 550 and 1500-1600 in turbocharged form. Really close to modern C15s and ISX engines (about a decade) which I'd say is respectable for an engine from the 60s

DoubleVisionandco pound for pound you mean inch for inch a 4 stroke with the same cylinder count will be a massive displacement compared to a 2 stroke pound for pound and diesel mechanics agree a 2 stroke is pound for pound a better power house

DoubleVisionandco yes it is espeically in a tractor

jdr ok...... it takes a 4 cycle diesel of approximately 33 percent More ci to produce the same amount of power output as a 2 cycle Detroit.... or most any 2 cycle diesel of similar design. All the "Large" diesels in the world that are used in very large industrial and Especially in large marine applications that are in excess of 45,000 to 50,000 hp.... are ALL 2 cycle design.

DoubleVisionandco..... Not entirely true, Detroit (2cycles) produced (still do) more power PER Cubic Inch of displacement, than Any of the 4 cycle diesels (Cat, Mack, Cummins, etc) ever did... even after they started turbocharging the 4 cycle diesels for truck use (mostly starting in the 1970's). Prior to that time period, when ALL of the diesels in heavy truck use (OTR semis, etc.) were NA (Naturally Aspirated).... the 2 cycle GM Diesels were literally "king of the Hill" (mountain grades), as they would regularly "walk all over" the 4 cycle diesels, loaded or empty... especially in the mountain grades.

+Mike Berg Yeah buddy!!

I sure would like to get a tour of that barn! Thanks for the comment!

Those tractors didn't come from the factories with Detroit Diesels in them.

Unlike a two stroke gasoline engine, fuel/air does not enter through the crankcase. The crankcase of a two stroke diesel is filled with oil. Air enters through ports on the cylinder wall which become exposed when the piston reaches a certain point. The Air is then compressed and diesel is injected somewhere close to tdc. It ignites due to the high pressure and temperature. That's your power stroke, then the cycle repeats itself.

Thanks dirtbike5100 Engine designs intrigue me.

Yep. What dirtbike5100 said. And it can be oiled just exactly like a "normal" 4 stroker (no fuel-oil mix, but pumped throughout instead) simply because it is force-fed from blowers. That's how it scavenges. All Detroit 2 strokers have a blower (or blowers) and FOUR exhaust valves per cylinder. As soon as they open. the piston uncovers the intake ports near the bottom of the cylinder and the pressure created by the blower blows fresh air in and helps with the exhaust evacuation.

***** The answer is simple. the crankcase is wet sump like a conventional 4 stroke. These 2 stroke Diesels have 2 or 4 exhaust valves in the cylinder head (operated by camshaft and rockers in the identical petrol engine way) and a ring of intake ports in the cylinder (in a similar 2 stroke motorcycle/lawn mower etc) way. Since it is Diesel then only air is blown by a Roots Blower into an air gallery surrounding the cylinders which is separate from the crankcase. Just as in a 2 stroke dirt bike, the piston covers and uncovers the ring of intake ports. The fuel part of it injects the fuel via a unit injector ie one injector per cylinder, operated by the exhaust camshaft and rockers. On the cam there is a seperate love for the injector rocker arm. The injector has a piston inside and the Diesel fuel is injected into the combustion area via the exhaust camshaft rocker arm. The blower DOES NOT provide for positive boost, but must be used for start, idle and lower RPM. This style of motor is called a UNICYCLE Diesel. Some do have turbos that feed into the blower. The turbo Unicycle Diesel does provide for positive boost, however the blower only ones are designated N for natural ie 12V71N, or 8V92N. Proof that the blower does not provide boost is the Detroit horsepower graph for their engines. The graph shows how the power substantially drops off (like any other naturally aspirated engine) with altitude and temperature gain or a combination of both. Turbo engines remain constant so a 475hp 8V92TA produces nearly the full 475 regardless of altitude or temp.

***** and 2 stroke diesels have to have superchargers to feed air due to high compression so when someone says its supercharged and it a 2 stroke its considered naturally aspirated but ive seen them with turbos on top of superchargers

Mattywho that’s right. I hope my kid gets cancer.

Not that big of a deal

Zoidlrrr That's from the vaccines , not the smoke .

Hey guess what! I already knew it's a two stroke because I have 5 of them :)