Why Diesel Engines Lose Power & Efficiency Over Time 

I think it’s safe to say every engine loses power and efficiency over time...

They should have outsourced the testing to VW for even better results.

I just watched a 13 minute Exxon commercial. You win.

Pretty remarkable how much engineering is behind dinosaur boom juice

My stock Mercedes 300d was dynoed at 495k kms and it made 134hp. It left the factory with 136hp

I can't believe I just voluntarily watched an infomercial.

Hi, marine engineer here with a suggestion! I understand that your channel is about the engineering inside a car, howerver I suggest for your channel to take a field trip to a producer of marine diesel engines, eg. Wärtsilä. These typically are very large diesel or BI-fuel engines. With the engines being a lot larger than the ones found in a car, all the components are too. This can really help as a visual aid for your audience. For example: I used to work on a vessel using 4 Wärtsilä Sulzer 8 in-line 400mm in diameter making more than 4000KW per engine for propulsion use only, running on IFO360, MDO & MGO. Normally each cylinder has 1 fuel injection pump delivering the fuel at +/- 380 bar at a viscosity of 2-4 cst. However, the new type of BI-fuel engines have multiple fuel injection pumps per cylinder. These fuel injection pumps are actuated by the camshaft and are about 50 cm tall. If you want more info on marine application engines, feel free to contact me.

9:26 200k? In Romania we treat a 200k second hand vehicle as new.

I always find it funny when a title is not what the entire video is about, only part of it, because then you can scroll down to the comments and see easily who commented before actually watching the video. Great video, Jason!

Take a shot every time he says "Synergy Diesel Efficient Fuel"

This video was proudly brought to you by Exon.

Actually, remember this from school. Only stayed in my head because it had to do with cars

When Rudolph Diesel introduced his engine in 1900, at the World's Fair in Paris, it was running on peanut oil.

2% is a very small margin to work with. When you consider the additional cost of the fossil fuels used to make these additives (both in energy and materials), this leaves even a smaller margin than 2%. Also, just replacing the volume of additives with diesel fuel itself might be enough to make up a 2% difference. I also understand that the additives are not just to improve fuel economy but also stabilize the fuel from degrading and other functions as well. However, in my line of business, if I were to propose adding a whole new, complicated process (that requires additional facilities to develop it, factories to produce it, storage facilities, distribution (to all of the refineries), etc) to improve

I work in a diesel shop on semis, modern engines and high pressure fuel has ruined so many people's engines its not even funny, drivers O/O report no fuel economy increase, but maintenance and repair costs of the emissions systems are unsustainable, go buy a semi Nox sensor or dpf filter, and youll see what im talking about, not counting the time in diagnostics, that is its own nightmare.

Do you have a video on the effects of the diesel exhaust systems causing additional fuel economy losses?

How much extra do they charge for 2% improvement

NOx is far bigger problem for people than CO2 since CO2 doesn't cause SMOG. 11% reduction in NOx is HUGE, sounds way too big of a claim. Is there another independent source that verify this? Another question, what combustion toxic emissions are produced by the detergent?

Another inefficiency is happening in the air intake stream due to sludge accumulation. This sludge is caused by egr and pcv mixing oil and exhaust soot. A 3 inch air stream can be significantly reduced withing 150,000 miles.

After learning about Diesel Particulate Filters, it is nice to appreciate the details about solutions for diesel engines. The "Regeneration" process to remove particulates was interesting to learn about. I'm glad this video gave a lot more info about these engines. I now have more sympathy with my fellow truckers on the road and mechanics in the shop. Thanks for the insight!

4:10 « over 2000 bars » Thanks for that unit choice man

You left a lot on the table. The new injectors are more than higher pressure and finer spray. They are electronic and injection timing, duration and flow is infinitely adjustable. Most older diesels have mechanical injectors and timing fixed. This is the idea behind CR or common rail, a very high pressure pump feeds electronic injectors which are individually controlled and chamber pressure is monitored. The timing, duration and rate are precisely controlled not possible before.

Finally the white board is back. Thank you professor 😂

A follow up video for off the shelf diesel additives, and there effects would be intresting to see as well.

2% on a drive by wire, and measured at the driveshaft. In the real world, everyone is gonna pay more and not gain anything.

Just 200k maximum life for a light duty diesel engine doesn't sound right to me.

Crazy how my 1997 Powestroke gets 22mpg and seems to have better power at 375,000? Until recently WVO was my main fuel. Better mpg, quieter, smelled like cinnamon crispas!

82 Datsun 720 pickup, bought new, powered by SD22 Chrysler Marine diesel build under license by Nissan. 36-37 MGP city or highway. Had 387,900 miles before I give it up due to deterioration of body, interior, steering, suspension and power train. Went to start it for buyer after having sat for 1 1/2 years in wet Western Washington State. New batter, a couple of revolutions and boom! Away she went just like every time I had ever tried to start it!

Hi! Great video! Here in Portugal we have premium diesel and I can say that using it makes my car run smoother and I get a tiny bit better fuel efficiency. As for performance, in 1.4 liter engine you can feel slight increase, but for bigger engine there’s nothing you can notice. Cheers

Despite every downside of diesel engines, I'll be a "turbo-diesel head" forever.

mine 2.0 tdi still runs great at 150,000 miles i just love the massive torque it gives.

Fantastic!! It's really nice to hear that some companies are actually working at making diesel engines more efficient!! Rather than the constant negative reaction and attitude towards modern diesel engines that is so common.

Remember, Herr Professor Doktor Diesel himself designed the engine for peanut oil and similar raw vegetable oils that farmers could grow themselves!

Question: Were the injectors visually compared before and after testing? If so, what did they look like before and after. Do you have any pics?

Lovely thank you great vid, as always I do enjoy your delivery ...easily understood and well presented .

Please make a video explaining how DEF helps to eliminate NOx? It would also be cool to get a better understanding of the different sulpher levels in diesel. In South Africa, it's still pretty common to have 500ppm diesel and the lowest on offer is 50ppm. I know this value is significantly lower in the USA, Australia and Europe. Thanks for a very informative video as always!

You cannot have a diesel video without paying homage to the mighty 7.3L!

who thought there was a point to trying to disguise the Ford logo on the white pickup?

jason somewhat resembles better call saul when explaining

diesel engines nowdays utilise EGR and turbos; the carbon build up over time blocks these ports, so the power performance isnt run to engine designs.

Finally a diesel-related video on this channel. Thank you, Jason!

You should do a video on the wear and tear city driving vs highway driving. I've heard a range of different studies on this.

I love your explanation and really appreciate the amount of effort you put into making these videos.

please make more content about diesel engines, they're so awesome

People hatin' on VW diesels, but my buddy's '99 Jetta TDI recently rolled over 500K(kilometers, not miles). Pretty damn good regardless...

The distillation process is performed not only by heat but under pressure. The process is known as "cracking". The alternative method would be a centrifuge. A more accurate explanation of why fuel ignites in a diesel engine is "heat of compression". Timing refers to the opportune time to ignite the fuel in a given stroke. Lastly, I believe the Exxon additive is essentially a catalyst that organically bonds to impurities either in the fuel or byproducts of combustion in the engine and enable the particulate to burn off.

these videos make my day. learning something new is always fun especially when it's useful information.

Great question, cylinder penetration is the velocity that the fuel enters the cylinder. Remember that as the piston is coming up on the compression stroke, depending on the piston top, it will make the air in the cylinder flow in a certain direction and the injector orifices or holes have to point against the direction of the "swirl" so that the highly pressurized fuel will crash against the air and bond the oxygen molecules to the fuel and burn more efficiently. These guys that design these engines have my respect. And mind you that on electronic engines, they anticipate almost all possible failures and they put a response, a series of steps from the protocol in the ECM to protect the life of that engine. There's just so much that it's fascinating to me.

I always loved diesel topics, thank you Jason

Jason, Can you do a video on diesel exhaust after treatment? I feel like there are a lot of misconceptions about how they work and what exactly it is they do to the exhaust on diesel powered vehicles.

Thanks for this. We love our 30hp Yanmar 3GM30 in our 36’ sailboat.

Diesels are actually the most durable & reliable engines

So, I'm buying a semi for the next family road trip...

Cool video, very informative, but the real question that needs to be answered is what your age is. Are you 25 or 45? I’m lost here

I have a question. I stored diesel gas in a plastic gas container that used to have unleaded gas in it (there was still a bit of a gasoline smell) because i had no where to put it. Would it be safe to put that diesel that was stored there (for like the last 3 or 4 weeks) into my diesel truck fuel tank? Any help on this would be great.

Like your videos and watch them often - so thanks for breaking things down on the newer end of the spectrum. On that note - you State that the engines/vehicles were used and had reasonable miles on them with plenty of useful life. However, you also state that they were brought back to mechanical soundness as if there were new and various filters were cleaned and etc. So here is where I question the results - would it be better to take the truck/rig as-is and run the fuel to see what results you get? Point being that if I have a LD truck and and it only has 50k on the ODO, I am not going to start replacing or cleaning everything. If I were to run this test i think i would do it in four stages 1. Run the truck from new and measure the results 2. At XX,XXX miles Run the test again and see what results I get 3. Rehab the sensor and filters and see what results you get 4. Run the test again with the reformulated diesel and see what results you get. What I want from the above is the whole bell curve - I want the universe of data. I want to see my SD change after the introduction of the reformulated fuel. How do we know it wasn't the rehab that caused the desired results? I may be missing something here, but hope you understand what I am trying to get at. Cheers - Henry

My 2005 Mercedes e320 cdi (diesel) dyno'd at 205 HP at 457,000 miles on the original engine. The car was rated at 201 hp new

Make video about evolution of AC in cars.

Yes, yes, Professor, this was a brilliant lecture. I feel like I'm back in Thermodynamics class.

Thanks for the effort, video's like these are a ton of work.

This guy is really, really clever. I learn a lot from this videos, both things I maybe should have known by myself, and a lot of completely new things and new angles. Big thanks for this!! People, of all countries, how many of these really skilled guys run our countries around the world?? Not many here in Norway, I can tell you that:-)

My Golf mk4 TDI had 131HP when it was new, now has 220HP. 🤔😂

Nice. My grandfather built and ran one of the refineries for Standard Oil on Aruba, pre war. He distilled hi test which was used by the RAF.

Excellent. Thank you for explaining all this. Now I know why I bought my Chevy Colorado ZR2 Duramax. I love it.

Does fuel economy, CO2 and NOx emissions depends on the air temperature? On a hot day or on a cold day there are more CO2 and NOx emissions?

So they make engines more efficient but they got less efficient faster than the older designs, got it 😄

Can diesel injectors be cleaned? If so is it best doing it manually by removing them or through the use of additives such as Redex, Wynns etc. Lastly, is this worth doing on an engine with say 100-120,000+ miles?

In your video, when talking about the distillation part, I was wondering where they get the stuff for making plastics?

THANK YOU JASON!! We pretty much exclusively drive Diesel's here in Europe (and the UK) because of the *huge* tax put on fuel, we need efficient yet most of the time, powerful vehicles. Please keep including Diesel facts in your normal videos!

Great explanation of the basics and the science behind some improvement efforts. The real takeaway is what appears to be insificant improvements are much more significant when volume consumption is considered. The holy grail combustion engine race has always and will always be run in baby steps.

20 seconds in and I admire the quality of the sound

hi, do you recommend using fuel additives like fuel injector cleaners to keep the engine running smooth? if so, any particular brand? thanks.

At what RPM and Load does a Diesel Engine operate the most efficient?

Jason talk about the science behind making cars/ engines which can run on h2o...

Onething you forgot in this video, you didn't mention cetane number. It also determines quality of diesel fuels.

What happens when you lug a vnt turbo diesel engine, is the black smoke and sticky diesel at the end of the tailpipe from the process something to worry about if it happens frequently?

Very interesting and well explained. Thank you.

i learned more in 14 minutes than 4 hours in school

This is the best video you've made this year and exactly why I subscribe.

I always learn a bunch from your channel!

Smaller holes + higher pressure definitely does = better penetration.

The 2% fuel savings only occurs against a dirty engine. There's no difference vs a clean or new engine as I understand the presentation. Although, I suspect if the injectors were really clogged and if this additive could clean them, fuel savings would be even more significant. In as much as we know that standard fuel works overall fine, based on the trucks already out there running without the new fuel, the difference in price of the new fuel is most relevant to whether it's worth using on a regular basis. If the new fuel was the same price or less expensive than standard fuel, buying it is a no-brainer. If the new product is more expensive by more than 2% it gets harder to justify. Noting that the new fuel does nothing for an engine that is already clean. So in short, if the new fuel is locally available at the same price, it's a good deal, but if it costs more and requires a longer trip to obtain, it might not be justified for regular use... Lastly... it's getting kind of old hearing oil companies use the term "proprietary". If I buy a cookie, I have a right to know what's in it. When I buy gas, its a state secret. If someone really makes a better product, why are they afraid to tell us what it is? If Exxon is better than Shell, they should tell us why. If oil companies were transparent, we could evaluate the products against each other and the competition would actually lead to better products and fewer 2% better economy claims based on a single "fair" test criteria. Consumers and even most testing labs can't fairly evaluate the components of fuel or lubricating products at a molecular level. This means we have no objective way of knowing what is good, better or best and allows oil companies to pretty much claim whatever they want, knowing that no one can dispute their claims.

US needs to borrow some ideas on diesel fuel production from Europe. We’re missing out on this efficient fuel and long lived engines.

[PV = nRT] for the compression ignition win! Love your vids, Jason! Keep up the good work 👍🏼

excluding 1.9 tdi

I love watching these videos and seeing the data. I would love to see some of these data sets to test in Minitab. I'm sure they are spot on.

I'd like to know if there is a particular brand of truck stop that will carry this for use in my semi...

A euro vs US comparison on the quality for the diesel fuel could be a good follow up..

Man I heart me some big ol diesel engines. More diesel vids please!

My favorite channel for geeking out on car stuff.

Like always, great video Jason! Love the channel!

It depends on how you take care of it. I have a 15 year old car with diesel engine, works the same as first day. Has not lost any horses :D

Do after market fuel system / injector cleaners actually work?

Is it true that you have to keep the rpm over 2000 for the best fuel efficiency on a tdi engine? How much difference is it gonna make and why?

It's called a fractionating column, not 'distillation column' 1:20 Also you have 'gasoline' at the top when in actual fact there would be at least propane and then butane above it.

The diesel fuel standard for UK is EN590 which has a cetane value of 49. Shell Optimax diesel is 51 to 53. I assume Exxon has their equivalent. Higher cetane numbers means smoother combustion less knock, less smoke and less NOx. The USA allows a minimum cetane of 40 so they have a lot of room for improvement.

damn, that's some serious test engineering!!! *RESPECT* lol, a 2% increase in efficiency for a long-haul trucking fleet means significant money.

Hey dear. Very informational video. Keep it up. Well, i have skoda octavia rider 1.9tdi diesel 2007 clocked 1 lac kms on odo. Will it be fine if i use Liqui moly Diesel purge in full tank to clean injectors and fuel system? Is it safe? Please let me know. Thank you.

So, no mention of cylinder wear and compression loss. Every OTR truck driver is probably familiar with 'blow-by'.

I thought any engine looses power and efficiency over time 🤷🏼‍♂️