How does a Detroit Diesel two stroke work?

In this video I quickly run though how a traditional petrol 2 stroke and 4 stroke works then talk about how a Detroit Diesel 2 stroke engine works in comparison.
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[@storbokki371]

7:05 "This is the piston liner from a Detroit diesel..." from a guy in Australia wearing a Freddie Mercury T-shirt with chickens strutting and clucking in the background trying to steal the show. Yes, there are still things in life that I could never of imagined seeing even at near 60 yrs. How surreal. Love the experience and knowledge you pass on. thanks

[@DangarMarine]

That pretty much sums up KZbin. :)

[@jaquigreenlees]

That is actually the clearest explanation I have seen as to what makes a Detroit Diesel so unique. Well done.

[@mumblbeebee6546]

Agreed, thank you for that great explanation!

[@DangarMarine]

Thanks mate, glad you liked it.

[@markbroad119]

I almost typed the same thing. I feel they should re-make the 2 stroke

[@jaquigreenlees]

@@markbroad119 they should start making them again.

[@johnhhinton5473]

@@jaquigreenlees No way to get them to comply with emissions laws. :(

[@jaredrobbins2120]

You’re great at not wasting any time just getting to exactly what is in the title of the video! Thanks! I was curious what the differences were btwn the 2-stroke gas and Diesel engines and now I know

[@DangarMarine]

Glad it was helpful!

[@edwardparis3043]

I saw this video last year and watched it as a refresher. It is still as good as the first time.

[@gnrphil]

I worked on US military vehicles with these engines and although I understood the basics of how they worked, I never understood why they had a "Blower" and a turbo. Thank you for clearing that up.

[@DangarMarine]

You're welcome Phillip.

[@markiefufu]

I really enjoyed the video. Not only did I learn how a Detroit Diesel works, but I loved the scenery!

[@dawgwithabone6826]

When you say you're not an expert, your explanation is far more concise than I've ever gotten from a grade mechanics on this subject. ABSOLUTELY OUTSTANDING VID ON THE INNER WORKINGS..👍

[@chrisbyers6084]

I've been running a 1947 Allis-Chalmers Road grader for 30+ years. Now I understand a lot more about the Detroit Diesel that powers it. Antique engine but give it a shot of ether and engage the starter with ample juice and it still fires right up. Massive power.

[@damienquinn]

We have a Detroit Diesel at work to supply backup power to the entire TV/Radio station. Each Detroit has its own 'personality'. Can't wait to see what your Detroit's got in store :)

[@krissfemmpaws1029]

I have seen them take years and years of abuse and keep on going.

[@nikolabolic7120]

Do you know when Detroit Diesel stops leaking oil? :D

[@Hoaxer51]

Nikolai Niko, I’ll bite, when does a Detroit Diesel quit leaking oil?

[@silasmarner7586]

@@Hoaxer51 I think his answer is "I don't know, and neither do you!" hah hah!

[@captpepin]

Great video, very clear explanation of how the DD works and by comparison to 4 stroke and “Traditional” 2 strokes. I’m puzzled why even 1 thumbs down?

[@daleskidmore1685]

That is the most concise explanation of a 2 stroke petrol engine I have ever heard; I learnt something!. The Detroit talk was equally as interesting too. Very cool engine.

[@DangarMarine]

Thanks Dale!

[@svendholme3627]

Thank you Stew, I learned something new this morning. I basically knew how a 2 stroke diesel engine worked but did not know about the low pressure feed for the injectors and that the injector itself created the high pressure. Yesterday I watched "Bus Grease Monkey" hold a frozen injector in his hand and tapped the top of the injector with a hammer to create fuel spray. Now I understand what he was doing and why.

[@DangarMarine]

Yes, that hammering is a great demonstration of how these injectors are the pump themselves.

[@trevorpom]

Good explanation. Just one more thing to add tho. If a Jimmy(nickname for Detroit Diesel) isn't leaking oil it's busted. The airbox drains always leak a little oil. If you don't put a catch can on, and regularly drain it, there will always be a puddle of thick black oil under the engine. It's even worse in a confined engine bay like the trawler. If you ignore the catch can then the BILGE MONSTER moves in with a vengeance and stinks the whole place out with oily sludge and all the other detritus that falls in with it. It's a unique smell that never really washes off, you or the boat. You'll stop noticing it, your friends and people you've just met won't.

[@DangarMarine]

Yes, there was a catch can installed in the boat originally, but I didn't particularly like the way it was done so I am going to make up a new one.

[@AW-zy1kw]

I have no fuel gauge and ran out of diesel on my 8V71 so unlike the high pressure types no bleeding required to get her fired up again. Hope I did not damage any injectors! Excellent demonstration of a 2 stroke DD.

[@newjerseybill3521]

Excellent class, Stu!!! Hard to believe the 6-71 was introduced 81 years ago, and that almost all of the parts from a 1938 6-71 are interchangeable with todays 6-71.

[@DangarMarine]

Thanks Bill. I hope we do a celebratory lap around the island for the 100th anniversary. :)

[@dfo105055]

Yes well done Sir. That is one of the best explanations of a two stroke, four stroke and a Detroit engine mechanical process. I have taken a 1988 Yamaha 25 two-stroke under my wing that was not running and with your help it is now a smooth running reliable engine from top to bottom. Thank you sir

[@boothienz8021]

Spent meany a year sitting behind a 3-53 Detroit 664 Clark skidder, the 2 stroke Detroit is an awesome engine!

[@krissfemmpaws1029]

The 53s are near indestructible

[@seanthornton4382]

Thank you - learned quite a bit and answered all the questions I was seeking answers to.

[@propdoctor21564]

Excellent video... I have never owned a diesel car or truck but have owned two-stroke motorcycles and outboard motors so I understand their operation and being a car guy all my life I completely understand four stroke engine operation so this was very interesting and explained very well so now I completely understand how this works. Thanks much !! 👍👍

[@jeremykamel9655]

When I was in diesel school we actually took one air box side cover off while a we had a 6-71 running. Very cool to watch the piston. Just don’t whack the throttle while it’s off because you’ll get a face full of oil. Another fun fact. Because Detroit are the type of two strokes they are. The upper crank bearings see almost no wear along with the lower rod bearings seeing almost no wear. I’ve heard of guys just replacing the worn half’s of the bearings of budget rebuilds. Great job explaining the combustion process. Teaching is cool! Cheers

[@DangarMarine]

Thanks would be cool to see!

[@peterkolle4150]

Never knew how 2 stroke engines worked. Thanks. I have been educated. Keep them coming.

[@ChaosExplained]

At 7:40 i about lost my sh!# 😂 "im filming here dude" Good video man, i bought one of these and trying to learn more about it

[@yohon1550]

THANKS, I JUST WATCH A VIDEO A WAS CHANGING THE OIL ON A DETROIT AND IT GOT ME WONDERING, SO GOOGLED IT AND YOU ANSWERED ALL MY QUESTION . SORRY FOR THE CAPS.

[@barrchgo]

I learned a long time ago about bleeding fuel lines of air, but I never understood why they didn't clear themselves until today. Thank you!

[@dmc2554]

Those Detroits, they are really quite elegantly designed ! BUT there's MORE !!.......The head can be swung 180 degrees if you want the exhaust to come out on the same side as the blower to facilitate a turbo charger feeding the blower, (or some other reason...), with less plumbing involved and it saves space in the engine room. The camshaft, mounted high in the motor (hence: no pushrods!), is removed from one side and is installed on the other side to make this work. The bearing journals are already there!! Everything important is Gear Driven and the timing marks are already there, too. Also they can be made to turn in the opposite direction! This helps in marine applications with 2 motors to cancel torque reaction of the boat. In buses and coaches it is said you can get a million miles before major overhaul; these motors WANT to run..... P.S.(Might want to consider a flapper valve to fight runaway condition). Long Live The (Detroit) King!

[@shipessex]

Plus, on the side opposite the cam you have a balancing shaft which is swapped with the cam when you change sides. Nifty.

[@gh0stchannel19]

I was just thinking that a Detroit diesel was just a Diesel from the city of Detroit. I'm feeling pretty stupid right now. Love the video again Stu! Keep it up!

[@newjerseybill3521]

Well, in a way, it was. Detroit Diesel was a division of General Motors, in Detroit Michigan. Detroit Diesel is now owned by Daimler AG. :(

[@gh0stchannel19]

@@newjerseybill3521 Thanks for the explanation. Sounds like you don't like that change?

[@newjerseybill3521]

@@gh0stchannel19 It's kind of ironic that the engine what helped win WWII, is now owned by a German company.

[@gh0stchannel19]

@@newjerseybill3521 That's indeed ironic. I must say that, as a citizen of the Netherlands, we are used to Germans digging in on our beaches during the hollidays again like it was in the past. 😉 And as a matter of fact we're actually fighting side by side with them in countries like Afghanistan. Also pretty ironic considering the past.

[@rays2877]

I'm from BC Canada, out traditional industries are fishing and forestry. Those Detroit Diesels were used in fishing boats and logging machinery, and referred to as Screaming Jimmies. Detroit was a division of GM. Noisy, hard on fuel but very reliable.

[@DangarMarine]

The reliability is certainly the thing I am most after in a single screw boat.

[@jimh.5286]

Very interesting, I'm glad the chickens allowed you to continue and finish your summary.

[@robertI153]

The screaming jimmys had a reputation of not being the most fuel efficient, but they are ultra reliable. Which is what is needed when out at sea. Good luck with the installation Stu.

[@prevost8686]

Robert I The fact that there are so many still around is a testimony to their reliability.

[@DangarMarine]

For sure, that is definitely the main reason I am happy to have one in a single screw boat.

[@afriedli]

The clucking chicken on your video reminded me of my late father who worked as a hotel chef and had to work late shifts on a regular basis, getting home from work between 11 pm and midnight. We lived in a rural area and kept around 20 hens for eggs (and the occasional stew) with one cockerel. Any eggs the hens laid beyond what the family needed my mother used to sell. The stupid cockerel had taken to crowing at some unseemly hour well before dawn. I was woken one night at around 4 am to the shouts of my father and looked out of my bedroom window to see my dad in his dressing gown in the floodlit area between our back door and the chicken coop with a carving knife in his hand. The cockerel had evidently woken my dad up one too many times after a late shift and now my dad had murder on his mind. Luckily for the cockerel my dad was too slow to catch him, and after a few minutes my dad's temper abated, and he gave up the chase and went back to bed. Chickens are evidently smarter than we give them credit for because thereafter that cockerel gave up his nighttime crowing habit, lol.

[@DangarMarine]

They can learn! :)

[@liftmanleigh]

Great explanation stu. Informed educated and entertain all-in-one video on a Sunday morning. Thanks a lot

[@DangarMarine]

You're welcome Richard. :)

[@tonysargent1699]

Nicely explained Stu, lots of knowledge passed on that is greatly appreciated. Thanks for sharing.

[@rayg9069]

Good job Stu a more than adequate explanation of Charles Ketterings design. A few reasons why two strokes were better in the day, being two stroke twice as many bangs per minute for the same engine speed. This gave a higher engine power in a smaller package than other engines of the day. Being two stroke with those extra bangs makes the engine very fast to take load or change speed, one of the acceptance tests I used to do on generators was for a NA engine like yours to be able to take full 100% load in one step without excessive speed dip. I can't remember the exact numbers 5% transient for 2 seconds? something like that. Another advantage of the GM was the ability to burn almost any clean oily fuel, I had done tests running them on straight out of the ground Merreenie crude oil, Bio Oil, Jet A1, just put through a filter. They ran fine. The basic GM design is nearing 85 years old, it's only the EPA that stops them being sold today.

[@DangarMarine]

Thanks Ray. Burning almost any clean fuel is definitely something I like about them given this boat doesn't have a huge range and might be going into some very remote areas.

[@kentayres1819]

Great explanation of how a Detroit 2 stroke works but you left out the most important part. The sound of a screaming jimmy is like no other sound a engine makes you have got to love that sound

[@fposmith]

Fine explanation. Maintained and repaired many of these when I had my dockside service company before I retired. These are a favorite among farmers for irrigation pump stations as well. They give them years and years of trouble free service. If properly maintained, they are pretty much a bullet proof engine.You are going to have about as close as you can get to a brand new engine. Used engines like the two I found for you up in the North can be a tricky thing if you don't send off oil samples and get a report. I know the cost was pretty large for all that machine work but, at least you know for sure what's been done to it. Can't wait to hear you crank it up. Keep up the good work.

[@DangarMarine]

Thanks Doug. I too think it is going to run very well for years to come now. I would like to get a second engine like the ones you found up north to pull apart and learn from, the big trouble would be getting it into the workshop!

[@farny5557]

that was a cool educational video Stu, been around engines al my life ,62 now, and EVERY day is a school day cheers fella

[@cliffstevenson5773]

Wow I needed that. I've been looking at explanations and animations - but your straightforward summary was just what I wanted.

[@SVImpavidus]

Very good explanations. Ant, Cid & the Pooch crew.

[@frankie5341]

Read valves and blowers, so the redundant air goes to the next cylinder from the blower. That's answered a lot of questions. Love your two way radio minute 10.16 behind you, best ever explanation, keep thinking about how to improve things on a two stroke, true blue Mate. Thanks again.

[@Elinor_Scott-Lester]

Every day is a learning day, thanks for that!

[@randynovick7972]

Wow, two drops in a week. Love it, and learned a little bit, too. Many thanks.

[@justinsquire4212]

great vid..just explained or simplified my common misconceptions when talking diesels & blowers!

[@robmitchell3633]

A true work of art. Very much ahead of it’s time.

[@makeitwork583]

I like your informative videos, that was really cool. I like the ‘hybrid’ system the Detroit uses, seems to make sense.

[@jaquigreenlees]

Yup, but they do have a significant flaw that can easily be seen in BGM's rebuild vids. The intake ports get carboned over in time. The air intake plugged with carbon build up because of the design is a definite design flaw.

[@krissfemmpaws1029]

I have spent many hours running a Jimmy in marine app and can't think of a better engine to put in a work boat. I know of a few Alaskan fishing boats with over 20,000 hours on the on their Jimmy main engings and they have never been apart. Dad's boat was one of them with over 24,000 hours the last time I was on the boat.

[@krissfemmpaws1029]

@@jaquigreenlees odd we didn't have that issue. I think that may have to do with the grade if oil you use in it. All we ever ran was Delo 100 40wt.

[@brucefay5126]

The 2-stroke cycle DD engine was developed in the 1930’s. The 4-stroke cycle engines ultimately pushed it aside because of emissions (the 2-stroke cycle engines are not particularly clean burning). But many people have a deep fondness for, and appreciation of, the DD 2-strokes.

[@MattBargain]

Bruce Fay thanks, I was just about to ask why somebody would make a 2-stroke Diesel. Emissions then. Also higher fuel consumption and noise?

[@gregorythomas333]

Excellent description of these different engine types :)

[@jonc1736]

Probably my fav video from you so far. Love it.

[@DangarMarine]

Thanks Jon, glad you liked it. :)

[@coldfiredog]

Excellent explanation of the Detroit two stroke cycle, and basic engine architecture.🙂

[@jonoedwards4195]

Great episode! This Build has become a Must see for Me and no doubt for all the rest of Your Subs. Beauty DM, unreal stuff thanks.

[@DangarMarine]

Thanks Jono!

[@JamesJ7851]

Thumbs up. A refresher from high (secondary) school, engine and automotive courses.

[@alastair2001]

This is one of your best videos! Really clear explanation lovely to listen to and clear diagrams. Keep up the good work

[@DangarMarine]

Thanks mate. :)

[@ivogiev]

Just learned something new. Thank you for the great content.

[@smithcalvin]

Loved the video, I had never thought about how a diesel works. Thank you very much.

[@EdwinSteiner]

Great explanation, thanks! Now the words you say during the restoration make a lot more sense to me.

[@davidapp3730]

Great explanation with props of the operation of the Detroit Diesel.

[@andycumberbatch4140]

You are not a mechanic by any stretch of the imagination? Lol That's the biggest understatement of the century. I can just imagine, had you been you might have actually made an engine. Well done man, thanks for one of the best explanations on this topic.

[@korvtm]

Very accurate description of D.D function.Once worked on an old WW2 era barge that had 2 so called 24 Cylinder engines.Actually there were four 6=71 engines accached to a special gear box that drove a screw.The boat had two of these monsters each driving a screw. Talk about noise. The U S military used the DD engine in so many different things from Tanks to the Gamma Goat.I personally have been able to work on the 3-53,the 6v 53,the 6-71 the,8v 71 ,and the 12v92. Love the DD.

[@DangarMarine]

Thanks mate. I really like these Detroits too!

[@vanzi2834]

Very informative thanks mate cheers from Florida

[@GregsWorkshopOregon]

You should do a video on the versatility of setup for Detroits. You can put the blower on one side or the other, exhaust on either side, starter on either side, dipstick in multiple locations, etc to work for your setup. You can set your twin engine up identically or to be mirrors of each other, etc.

[@ryleewatson6849]

That was a great vid! Thanks buddy stoked she is moving along. Watch every video

[@austinfanning8641]

I agree with one of the other comments it's a very good explanation, we had two or three Terex R17 Dumpers using the GM diesel engine with a blower box in 1971 in the Avoca Copper mines at that time

[@vindivergilio3482]

Thanks for another interesting and informative video. See ya in the next one.

[@gordonpeden6234]

Thanks for this vid Stu, Fascinating I think I learned something today. Merry Christmas.

[@DangarMarine]

Thanks Gordon, Merry Christmas.

[@TheGreatdane56]

Thank you thank you Stu for explaining that. It cleared up a lot of questions i had about that ! Thank you !!

[@dirk4926]

This was so helpful. I learned what I wanted to know. Thank you

[@chrisnorman1183]

The things you learn every day :) Cheers as now I know.

[@johnduffy7502]

An excellent explanation, Stu! I've never worked on a Detroit but it seems very similar in principle to the large B+W two strokes I sailed with (980mm bore). Those had a central exhaust valve in the top of the head and three injectors spaced around it. The big difference (apart from the size) was that we had a crosshead and a very long piston rod which had a sliding seal around it as it passed through what we called the scavenge space, and you call the air box. This piston rod gives you the possibility of a much longer stroke/bore ratio and therefore higher efficiency. Because we burned heavy fuel, sometimes quite high in Sulphur, it was necessary to inject a highly alkaline cylinder oil through quills in the side of the liner to lubricate it and neutralise the acidity of the combustion products. This was a total loss system, so a lot of this oil and carbon ended up in the scavenge spaces (air box) and needed frequent cleaning. Fortunately it was large enough to send people in! What interests me is how the conventional lubrication system of the Detroit copes with the demands of keeping the piston, rings and liner lubricated, and what kind of state the air box gets into after a lot of short runs?

[@mleugs42]

That was a really interesting video! The explanation was great, and the editing moved at a good pace to keep things interesting. Kudos!

[@DangarMarine]

Thanks Michael. :)

[@gregmirr]

Stu - Merry Christmas and happy new year from San Diego , Ca ..always enjoy watching the videos from the trawler & the workshop . Looking forward to seeing you cruising the Trawler .

[@DangarMarine]

Merry Christmas Greg.

[@dglasgow0]

Fantastic description. Thank you.

[@MrCalifornia1234]

Well done professor. 👍

[@iamtheverybestever]

So interesting. What a unique combination of ports and valves! Love it. Can't wait to see it come together. Good luck with the blower.

[@socarboy]

Fantastic video, enjoyed every minute

[@alfgjelsvik2286]

That is actually the clearest explanation I have hear as to what makes a Detroit Diesel so unique,now iam a DD mekanic ;-)thanks fore greate vid mate

[@DangarMarine]

I'll send you your certificate. ;)

[@frankbiz]

That was awesome, made me finally understand how they work. Great audio and visual explanation. I need both. Lol. Thanks. 👍🏻👍🏻

[@kglesq1]

Thanks Stu, that was a great video. Learned something new.

[@MrLukealbanese]

Outstandingly good explanation. Many thanks.

[@rudywoodcraft9553]

Great explanations--I learned alot--many variations I wasn't aware of!

[@Sfrrob1]

Nice explanation, so interesting to hear how they operate. Thanks mate.

[@tpcoachfix]

Carbon Monoxide, not Carbon Dioxide.. Good video Mate.

[@DangarMarine]

Much more carbon dioxoide than carbon monoxide en.wikipedia.org/wiki/Diesel_exhaust#Exhaust_gas_composition_according_to_various_sources

[@trolling4dollars816]

Thank you, I have wanting a video like this for awhile

[@DangarMarine]

You're welcome mate.

[@Crogue464]

Best video to sate my curiosity. Thanks mate, well done.

[@stuartkeegan2291]

I wish you'd bought a boat with a Napier Deltic... I'd love to have seen you explain a 3 crankshaft, 18 cylinder, opposed 2T diesel in layman's terms!

[@newjerseybill3521]

Every time I see that engine name, I think it is an enemy of Dr. Who. hehe

[@paulbateman3654]

what an engine!

[@thedredd187]

Accept no substitutes, Napier Deltic is the King of crazy diesels.

[@mitchellstadnik752]

Deltic is awesome, but the Fairbanks Morse is still in use

[@DangarMarine]

I want one! :)

[@nevets7152]

Thank you very much a great thought out explanation and easy to follow. Steve in Thailand.

[@richardbohlingsr3490]

Thanks for sharing that information.

[@stephen5147]

Good explanations. Thanks for the video.

[@Kimbeattie]

Thanks for the lesson, Kim from Canada

[@bobjoncas2814]

...great info., the work is lookin' good...

[@davidanderton2437]

Great simple explanation.

[@UrbanFisherman]

Thanks for the info 👍🏾

[@SailorBarry]

love the specifics, great video

[@87xfute]

Well done Stu, great explanation !! Seeya Rob

[@cliffthelondoncabbie]

Stew your amazing mate. I always wondered how a 2stroke diesel worked. Just never bothered trying to find out, now I know and life's just got more interesting. My benford rollers a two stroke as is my diesel mixer, both incredibly reliable, keep up the great work stew. Boat drinks 🍻Cliff the London cabbie

[@DangarMarine]

Thanks Cliff. :)

[@tuvia4082]

Good stuff, very concise. The Detroit Diesel is a workhorse when maintained properly.

[@edwardparis3043]

Very clear explanation. Good Work.

[@DangarMarine]

Thanks Edward.

[@Tux_Appreciator]

Very educational. Thanks!

[@markbroad119]

Best explanation I've seen. Thanks much

[@philowen2755]

An excellent explanation. Thanks.

[@DuncanMargetts]

Superb technical explanation.. thanks so much, learnt heaps.

[@Dan_C604]

Great episode, super interesting. Cheers!

[@fitzmeister5992]

A well done video. Thanks for the education!

[@learnapex2444]

Great job explaining that! I have a 453 Detroit in my 142 franklin log skidder and love it very fuel efficient

[@DangarMarine]

They are great engines the 4-53s. :)