*Engine for sale, like new, only used twice, serious inquiries only!* I kid, I kid! As a serious tip though, be sure to occasionally check your oil level, older cars tend to burn more oil and it's a headache that can be easily avoided by checking your dipstick while your car fills up with gas. If you're into Instagram, consider following: instagram.com/engineeringexplained/. For product links, check the video description, like this $55K thermal camera haha - amzn.to/2mgV8XS. Shout out to FLIR for letting me borrow the camera!
Engineering Explained I can imagine the engine without oil is actually hotter but because the readings are coming from the surface of the engine, the lack of oil only allows convection rather than convection and conduction.
I think the engine is hotter with oil because the oil carries more heat and keeps everything stable. WIth no oil, you have just air and that cools faster than oil. Air just doesnt provide enough cooling or and barrier in tight tolerances
I have a guess why this may have turned out this way. The engine is new. A new engine is going to have perfectly smooth parts and will therefore have minimal friction. As wear would increase over time, so would the friction. Another thought I had is that one of the main duties of oil is to be the weak point, and therefore break down instead of the metal pieces. when you combine these thoughts together you realize how the oil really helps; the oil prevents wear by sacrificing itself. Adding this thinking to engineering principles, you realize surface temperature at equilibrium is about heat added to the system. The combustion adds much more heat than any friction, especially in this system, which brings me to the next point. You used an engine with no load being put on it whatsoever and no idle speed variation. Having some sort of drive train would increase the heat from friction and the heat from combustion, due to the added fuel consumption of overcoming the external forces. The added load would also increase wear which would increase frictional heat more as the surfaces wear even more. Overall, the biggest problem with the test was having a new engine with no load put on the engine. I good way to show this in another test would be to take a lawn mower, make sure it has oil, check the internals with a bore scope, mow a lawn, check again, remove the oil, mow a lawn for the same period of time, check again and compare. I say lawn mower because it is relatively cheap and it would do the job of adding resistance, especially if your grass is tall.
FishMan72727 Eh, the system equilibrium temperature is equally a function of heat loss and heat added. Idle speed was a big factor in this test but load would not have mattered versus just RPM.
I work at a Nissan dealer ship, this person had their car towed in, 2016 rogue 26k miles on it. Driving down the road, heard a loud banging sound, car cut off, wont restart, opened the hood there was oil every where, had it towed to us. When was your last oil change. Never had one done. At 26k miles, with out a single oil change, the crank bearing (the one a showed in this video) seized, with the engine at higher rpms at the time, two connecting rods (the rod that connects the piston to that bearing) snapped off, and blew through the side of the engine block, leaving big holes. Probably the funniest part was when we went to remove the foam insulator under the hood because it was covered in oil, a whole bunch of metal pieces fell out :). This was not covered under warranty, for parts and labor you were looking at about $18k (almost as much as the car was worth), the owner had the car was towed away (probably to junk yard, but I'm not sure on that), and is now probably making payments on a car that they no longer have. Moral of the story CHANGE YOUR F%$KING OIL PEOPLE.
+Big Hoss I use my car for short distance trips so i'll reach the distance reported on the service booklet in something like 10 years and that's when i'll change the oil.
Kevin Weil - One day I noticed my sister’s Celica GT on the side of the highway and I stopped to see what was wrong. The engine quit and was smoking a bit. Checked the oil to find the dipstick bone-dry. I asked her when she had the oil changed last and she couldn’t remember. Asked her when she last checked the oil. The answer was “The Oil light never came on”. Engine was ruined. A friends brother was a mechanic at a Toyota dealership. He somehow got it covered under warranty. Cost her a case of beer for him and the service manager. Two years later, the same freakin thing happened. I was so pissed at her.
Kevin Weil I also work at Nissan and we had a 17 Pathfinder come in with 24k miles for an oil change, pulled the plug off and nothing was coming out lol so we drop the pan and there was no oil only pure sludge so thick that the pickup tube left an indentation in the sludge. This one got lucky the motor didnt blow lol
yeah, that would definitely help! I pretty much blew up a rototiller engine like this! It worked fine for about the first 5 minutes then it slowed down and and I noticed smoke coming out of the exhaust... yep, big problem...
There would be a significant difference, especially on the cylinder bore. The oil would reduce the friction and increase the heat transfer to the cylinder bore. The crank would also get worn to all hell
One thing you forgot to take note off is even though you drained the oil from the engine to do your second test without oil, all the engine parts would theoretically all be lubricated. Try running a completely dry engine with no oil and I bet your results would be drastically different
i like how this video was still posted in all of its honesty even though there was less than expected result. Scientific journals for example are now publishing "research" that have been tweeked to show a more conclusive result. Journals don't want to publish "boring" inconclusive findings. Hats off to this channel.
Plus it’s not going to stay cold, it would obviously warm as it travels through the parts that need lubrication, that’s why the temp doesn’t look to be cooler.
The oil not only acts as a heat sink, as you mentioned, but also as an internal medium to not only cool hot surfaces, but to warm cold ones...a thermal balance goes a long ways towards preventing material stress and abrasion at sealing points (gaskets, valve seals, etc)...running with no oil, the hottest spots are probably going to be the piston's crown, the cylinder head's combustion chamber (to a lesser degree), and the exhaust valve stem/face. If oil is present, these parts will give up their excess heat and spread it to cool spots, like the finned cylinder block and intake side of the cylinder head, but without oil you are going to notice slightly cooler external temps as no heat is being transferred, but critical internal parts (particularly the piston) are building heat and have no way to transfer it away aside from direct skirt/ring contact with the cylinder wall. Eventually, the piston will fail from overheating, either by cracking or swelling enough to seize in bore, and the excess heat from combustion and friction trying to leave the only way it can, by direct contact of the rings and skirt to the cylinder wall, will lead to very rapid wear. Some of those small engines have a cast cylinder liner that isn't particularly tough, and the hardened rings will wear it away faster than the piston can seize in it. Then, with even less direct contact, the piston is going to have to melt down or crack. But the compression may get too low to keep running before that happens, all depends on the quality of the build. The bottom ends on these use ball bearings, which can roll along pretty happily with just an oil film for a long time. On a car engine, with hydrostatic bearings requiring oil pressure to keep metal off metal, no oil pressure is an almost instant disaster...but really not that big a deal for these little ones, at least in that respect.
Interesting video, thanks for sharing. Three additional key points that you might want to make to your viewers are the fact that: 1) There was some initial lubrication in the engine that was drained and run with no oil and even that small amount of oil provides decent lubrication at low RPM's under no load. 2) The Second point is that this test was performed at low RPM, would be interesting to see it at half throttle for a few minutes 3) Lastly, it would be interesting to see the same test at half throttle under full load Thanks again for a well produced video.
What is really interesting is at 4:21 you can see significant bluing on the crank on either side of where the connecting rod and bearing would sit. That would seem to indicate the temperatures were actually incredibly high from the bearing running dry. Neat to see how that wasn't reflected from the external view. As always, love the content, keep up the great work.
Well, you were measuring temperature on the engine casing. With oil temperature can be transfer from moving parts to engine casing. Without oil parts inside (like gears) are getting hot, but air around does not trasfer the heat to camera. So this is why engine without oil is colder (but it really isnt).
no...it has cooling fins to keep cool...its doesnt even have an oil cooler and even if it did thats not what an oil cooler is for...its to keep the engine oil at optimal temperature which is about 212 degrees F ... oil is for wear protection not engine cooling
phil tripe The one exception to your statement is an engine with oil squirters for the bottom of the pistons. Ferrari and Mahle are even using a 3D printed part on the underside of their pistons in F1 this year, to better control the piston temps.
Normally in engine with oil inside just one of the 3 rings is lubricated, others are not, and they purpose beside keeping pressure is to transfer heat to the fins. So your analogy is not exactly correct, because with or without oil they are working in the same condition. Another thing that occured to me is, you test engine with oil, drained it, and then run without oil. Well, oil is dense, and you cannot drain engine completly. Very thin layer of oil remain on the insides of the engine. For lubricated parts the thinner, the better. Layer thick on several atoms works the best, and you need more time than 15 minutes to wipe that layer. The test would be more reasonable if you cleaned remaining oil with special thinner. It would result in metal on metal action, and fast destruction of engine.
My mechanic forgot to change the oil in my car in the last service it had 2 years ago. The oil was already about 2 years old. So 4 years running on terrible oil that was less than 3 litres when 4 litres I'm supposed to have. The oil filter was already broken. I'm surprised my engine survived. As soon as my new mechanic drained the oil, cleaned the pan and new filter my car burst into a new life within an hour. It felt more powerful. So oil is really important guys. You might be thinking why so long after servicing. Well the car is a second car that's not used as often. So didn't feel the need to.
dosmastrify in my opinion, when the oul is very dirty and thik, the oil filter wont let it pass because it gets clogged overtime, then the pressure of the oil triyng to flow will eventually break the filtering material inside the oil filter. Maybe thats why he said it was broken.
theninja001 Lol, the car is rarely used, maybe it gets 1500miles a year on it.. so that's why I don't get it serviced every year so I do it every 2. I didn't know the oil wasn't changed until my new mechanic told me it most likely wasn't changed. It was also low on less than 3 litres of oil when it should be 4 litres that's probably down to leakages over the years. But I'm taking care of it more now, because I want the car to go on forever. And the reason I didn't change the oil myself is because I usually go the mechanic to get the whole lot done In 1 go, brakes, engine etc.
Hi Engineering Explained. I have a 2015 Acura TLX V6. If you haven't already heard, this car comes equipped with a 9 speed ZF DCT that's been heavily criticized as being very jerky in shifting gears. Honda has been quick to swap out the 9 speed ZF DCTs for the 8 speed DCT. I've read some articles and forums stating the jerkiness has something to do with the "dog" clutch gears. I'm genuinely interested to know why these transmissions came out badly designed. Would you make a video explaining this? I hope my fellow youtubers like this comment to get his attention. Thank you all.
I heard that some tuning out a bandaid on that transmission.. they pretty much disabled 1st gear as the fix. I’d be upset . I do love the 10 speed in my F-150 though!
This engine has splash lubrication, the forces in the engine are relatively low and the bearings don't require pressure lubrication. In an engine with pressure lubrication running under load the engine would seize within seconds or minutes, once the oil pressure would drop the bearings would dry out and overheat quickly. It's an interesting video but can't really be compared it to a car engine. If you lost oil pressure while accelerating on the road you would probably end up stranded in a cloud of smoke and possibly with bits of engine rattling around the oil sump.
This actually happened to me. I was driving down the road when an oil cooler line gave out and blew it all over the road. I temporarily repaired the hose, threw a little oil in it, drove it up on a trailer, and took it home to fix the hose correctly. The vehicle still runs like it has all or most of its power and everything. It just clacks under load. I'm debating whether to put it back on the road until it truly dies but I'd have to replace some brake line first.
My 1996 Honda Civic Ex ran without oil for quite a while. The car felt sluggish and slow, but it kept going. One of the pistons had exploded and was making a terrible popcorn sound while idling. The engine blew and had to get a new one. But it did run for awhile without oil. To this day, I say Honda makes the best engines.
Or more to the point, it sounds like you kept driving the popcorn motor??? Not all noises are something you should worry about, especially at high mileage, but there are some sounds and actions a car makes that are universal for stop, CEL or not...
My mother got a Mitsubishi endeavor with 160k back in 2013 The car always made weird grinding noises but it was really speedy and never once even stalled or had an issue I never remember her changing the oil but I never said anything This week she came to visit and I was using the car with now over 200k she still never changed one thing on the car besides the battery and I decided to check the oil just out of curiosity and I was surprised to find the stick bone dry and the car wasn’t even knocking she said she never has time to check it and refuses to go to a mechanic because the car never had a problem I added some and the car already sounded so much quieter and felt new We still drive the car today and I plan to change the oil myself at some point She got a montero sport that she doesn’t treat much better but something about these motors just keeps them going All i can say is no other car brand has survived her long
"It goes against my intuition. But then again, if I knew what would happen from the start there'd be no point in doing this". Beautiful. This is precisely how humans went from banging rocks together to landing on the Moon and building supercomputers! Love it!
Jet Star One of car enthusiast channels in my country (Poland) did this using a 1.4 Opel Corsa, the guy was hitting redline frequently for a few hours straight and the engine worked as smooth as it was before. The conclusion was, this kind of oil will work, but it has way shorter lifespan than engine oil (it stops working as a lubricant much faster)
If you have to escape from the apocalypse and have no other alternative it might work. Just make sure you use cooking oil that can withstand high temperatures, so no olive oil =D
When I was 18, I took my Dad's Honda 350 twin MC for a short spin; real short, like a half mile. He had drained the oil, and took the key to get some new oil. With no sign of this in progress, I found the (spare) key (go figure) and took off. On his way back with the oil, he saw me pushing his bike back home. I was still unaware what had happened, though he was fully aware. He was very understanding and composed, as always,and we did get it running again...with oil this time.
I think - and you point this out - the oil is acting as a heat conductor, which causes the crankcase and cylinder head to run hotter, but allows the internals run cooler. It'd be interesting to see the experiment repeated, with thermocouples embedded in various locations ... which would undoubtedly be hard to do.
A better comparison would be between an engine with oil and a separate engine without. It would be interesting to see how the wear patterns. I would have also left it running for hours, and tried to break them in per recommendations. Cool experiment!
quite honestly if its api certified its fine. probably grade one or two though, which means conventional with no additives(grade one) or with (grade two)
I'm sure I'm not the only one who will request you do this test again. Some people will say this test was poorly planned and they would be correct, to an extent. However, this test obviously surprised you... And you can't plan for the unknown. It is a learning experience... I'm sure if you give this another go it will result in a video that is far more engaging to an audience who may not naturally see it from an engineer's view.
personally I can understand why it didn't act crazy after only a few minutes running without. for a small amount of time I'd wager the gearing and pistons would still be able to operate before they actually heat up and start grinding more. of course only for a very short period of time. I personally feel like if they both ran for say 6 hours straight, you'd see some extreme differences. then again I'm not an engineer and this is all conjecture feel free to correct me if I'm wrong
I loaned a tiller to a friend that operated it for several hours and never checked the oil when refueling, needless to say, it locked up. The difference between that engine and yours was he was operating it under a load and i'm sure at higher speeds. Thanks for demonstrating what happens. It makes sense that the block of the engine with out oil was cooler because as you mentioned part of the oil's job is to take heat from the piston and crankshaft and move it to a location that can allow it to harmlessly dissipate. If you had never added oil to the drained engine it probably would have locked up as soon as the assembly lube dried up..
To add, at 4:21 you notice a lot of "blueing" around the connecting rod journal. A sign of high heat. The oil not only lubricates but also transfers heat away from the engine parts. Interesting video. Thanks for sharing!
Engineering Explained seems that maybe that small amount of oil still inside the crankcase had quite a bit of cohesion on the bearing surfaces, and decreased friction just enough for temperatures to stay reasonable. would not have guessed that
My guess it survived that long because there was no actual load on engine. I remember Fifth Gear drained car engine and drove around with no oil and if i remember correct it survived 8 minutes.
Could also be loose tolerances decreasing friction since it's a shitty motor. I have a retarded friend who drained his oil and started his truck and had the cam seize to a bearing in less than a minute, and he didn't even drive anywhere (apparently).
It still blows my mind that I can buy a brand new (semi decent) small engine for $90! Like the others are saying, having a load on the engine would dramatically change the results. I think powering a water pump or large fan would be a great way to apply load, using a rig you could easily fabricate and store at home. Either way, keep up the great work!
Wasn't there a TV commercial for some oil company, years ago (probably in the late 70's-80's era) where they drained the oil and ran the car around the track to show the residual oil's lubrication ability? I don't remember how long they drove it like that, but at the end of the commercial, the car with no oil in it was still running well.
I believe that may be from the casting process, if you're referring to the coloring at 4:20. Not positive, as I didn't look inside initially, but I have a new crank as well and it too has the coloring.
It is markings of the heat treatment. After casting and rough machining, the bearing surfaces are heat treated for surface hardness and then ground to final dimensions.
you seem pretty smart but I was totally put off when you held the oil bottle the wrong way there's directions on it for you to pour it correctly so it doesn't gargle but nobody seems to read it it's right on the side of the bottle. actually I think it's a drawing I don't even think you have to know how to read just look at the drawing
+land otter1 your points B and C are the same thing. The higher Octane rating doesn't give the fuel more power it just increases its resistance to burning meaning the compression ratio can be higher and that is what gives more power. It also reduces the likelihood of predetonation for the same reason.
Too much oil can cause carbon buildup. I had a Solo 210 that got hard to start when the decompression port clogged. This put extra wear and tear on the pull starter and I wound up replacing some of that as a result. Cleaning the port involves removing the head and exhaust and then pushing a pipe cleaner through the port from each side. This is a periodic maintenance item on that engine but running say 25:1 instead of 50:1 would clog it up in only a few hours.
***** no it doesn't the lead was used so simply lube the fuel injectors. Seeing as all 2 strokes are carburated there is no 2 stroke engine in the world that would require lead in the gas. You can not have a fuel injected 2 stoke engine.
Fact is, the no oil engine did have some oil in it. If it had been completely dry it wouldn't have lasted any time at all. Even the small amount left on bearing faces makes a huge difference.
Castrol did those commercials a few years ago where they claimed an engine which had casttol oil drained from it lasted longer than any other brand. Have you done any similar testing and are their claims legit?
Interesting, never heard about that! It'd be interesting to see, but ultimately not that meaningful. If one works better when it isn't drained, that would be the one you'd want to buy, regardless of how great or poorly it acted once there was barely any left.
Hey engineering explained dude those engines always have metal shavings in the oil on the first run. I recommend breaking it in per the instructions and then performing this test, as I have two of these, and they both had metal shavings in the oil on the first batch of oil
the cylinder bore is supposed to look like that. the cross "grind" is there, so the oil doesn't flow down a straight line, but reaches all around the cylinder :) nice video and thanks for the test
I enjoy watching your videos with the thermal camera, but it would be better if you could hold the min/max values of the temperature scales constant. I understand that the method you use shows the most variability throughout the video, but makes it hard to see changes over time or compare two side-by-side images.
The variable that would apply in real world is engine load, as no engine ever just idles, they are meant to perform mechanical tasks. Try the same experiment with a load and watch the engine without oil blow up. Great video all the same.
The results are right! The oil makes the engine cooler INSIDE, exhaustingthe heat from it, and the thermal camera gets the temperature from the OUTSIDE, soh the engine with more exhaustingheat looks hotter.
I've topped up a 179 cc TVS motorcycle on Mustard oil and ran it for a couple of days because I was scared that I'll seize the engine because of too less oil. The bike ran absolutely normal with half a litre of cooking grade mustard oil and whatever engine oil was remaining in the engine from before. Ultimately, I did change the oil completely and filled regular 15W-40 oil.
If the motor was under load it would have had some sort of failure quickly. Surprised to see how little damage there was though. The blueing on the crank shows there was some real heat in there though. Good vid!
Once I repaired a " brand new " gas generator who's owner forgot to read the litle card that said you put oil before start the engine. It ran untill the crank shaft gripped! The cilinder and the piston didn't have visible damege. Atfter the repair, it ran whithout problems for at least 2 years, untill he sold it. Then I lost track of it. This shows how tuff these little engines are!
Great video! Running an engine under no load will eventually lose itself, but it'll take time. What happens is like you show and explain, the engine starts wearing from bearing friction. You put this engine back together and keep oil in it, it'll still last a long time, just not as long as it would have, LOL! I should say, the engine will last longer than a new engine that isn't taken care of. Proper preventative maintenance is the life of an engine.
One thing to note during this test was the engine is not under load. This means forces may be somewhat mild versus one under heavy load and actual use. It's hard to say how big a difference this would create as you are still getting moderate forces just from piston movement, but you are not getting the torque loading you would if the engine was actually worked. My guess is you'd see a vastly more rapid failure when placed under load. I just don't know the relative values and geometry to evaluate piston acceleration forces and a light rotating crank vs torque loading the crank and putting cylinder pressure forces to work. A blind guess would have me say the forces experienced would be vastly different, possibly some multiple of magnitude (10x, 100x, etc.).
API certification is API certification. Either the oil meets the spec or it doesn't. if the bottle says "WPP" (Warren Performance Packaging) on the bottom, they are a major player in the private label oil market and they bottle major brands as well. The additive package might be an "off the shelf" additive package in a grocery store labeled oil, but you could bet you life on the certification part.
When I was a young man I drove a Ford Windsor V8 about 3-4 miles without oil pressure. It survived just fine, but I did think to keep it at almost an idle getting home. Rattled a lot. Put in a new oil pump and kept driving it.
This engine faired pretty damn well for running for a half hour without oil, even without a load on it. I just got done fully tearing apart a 318 V8 that had been ran to its death without oil, and every single connecting rod big end bearing was totally shot, as with the crankshaft. There was also a piston that had totally melted rings and the entire skirt busted off.
Well, that metal content in oil is OK for brand new engines, even in manuals it says that usually after 8 hours of work oil needs to be changed as it will/may contain metal pieces
yeah i mean the engine was only idling too which obviously itd be hard to give the same exact amount of throttle both times, but the engine had minimal stress on it. plus with the metal shavings in the oil and and all that stuff, you will always get some shavings in the oil especially after the firt run or break in period. still really cool experiment dude!
We did something similar to this when I was at school. An old clunker was used, had all the oil drained, and then ran at full throttle! The point was to place bets on how long it would take for it to die. It took quite awhile for it to die (my memory tells me it was close to an hour and a half or so) and it wasn't anything spectacular, it just siezed up.
Man, I feel so sad... This is my favorite engine of all time... The 212 cc 6.5 HP Horizontal Harbor Freight Predator engine is so useful. It can be used for so many things! I have one installed in my "runabout" car. But, I guess it's a good thing to see what would happen if I did not check my oil...
Sir can you make a video on what would happen if one of your injectors (cri diesel engine) fail (i.e. leaking, clogging, etc.,)... Your videos are really educational and entertaining at the same time.
I think that assembly oils and lubes were still in the "no oil engine". A piece of silicone got pulled up into the pickup tube in a small dump truck I had, I saw the oil pressure gauge drop to 0. It dropped sitting at a red light and I only had to go about a mile and my engine (v8) was so damaged, that I bought another engine for it. Multiple bushings were damaged, valves were scored and stuck, cylinders scored as well. Very expensive day!
p.s. To help with all metal-shavings that form and are thrust through the engine-oiling system,it's best to attach tiny magnets to the oil-drain-plug and somewhere on the oil-filter!!! You'd be amazed at just how much those tend to collect after awhile!!!
At VW shows in the 80's they used to drain the oil from a running bug engine bolted to a stand and wait for it to explode. As you found out it's surprisingly long and often just a loud clunk followed by the disappointing sighs of the expectant crowd.
in the moment 4:20 you can see the "thermal affected area" in the crankshaft showing that it is losing its thermalmecanics characteristics, it was just a matter of time for it to lose its resistance and blow! (sorry my bad english)
They said a bit of Solid Lubricant as MoS2 (eg: LiquiMoly; Molikote A), [in the 70s this was done by adding a small Molybdenum additive can to new oil every time oil was changed] can help in avoiding or delaying enough this catastrophic result...
