F1 Pneumatic Valve Spring - A Closer Look - Ep 1

oh you're all very welcome and uh thanks for for tuning in so where will i start i decided to i guess start a channel on rare formula one parts or parts that would never be seen in the general public um there's a few very rare parts in the newer engines which have never seen the light of day or were very highly guarded i guess um through the years now i've written a lot online about various found one parts um you some of you know me it's uh it's brian g of uh f1 technical mainly i guess i've written a lot of articles on various formula one parents um now these parts have been obtained legally and all that um they're not you know off the back of a van or anything like that and they're all they're all legit and they're all mined so i guess i wanted to put a bit of scale to things and a bit of um you know a bit of reality to the the writings i've been doing over the few years you know um i think my first piece was done on oh geez what was it i think it was a formula one wishbone back about seven years ago um but i guess what spurred in the real early days was uh the volkswagen scene you know um i did a lot of work with 16 valve cylinder heads and all that uh i did a lot of publishing on forums as well of what you could port them to and what you could bring them out and all that and uh so i've been around engine since i was a kid um so i'll i'll break it into steps i guess i may pause it here and there but um let's talk you through what's what's what's it going to be about and all that you know so as you know in a normal engine um just to say first of all um a bit of an introduction i guess because uh there may be i guess 10 or 20 videos similar to this um i started off life as a as a cabinet maker um i i branched out then into making patterns for for casting and i got into casting in a big way you know because the the cabinet making skills directly relate to casting because you need patterns which are fairly well made in order to make the sand molds so it i guess i sprang into well i was always engineering background but the engineering came stronger then because i actually started designing the parts i was casting and not not actually casting them then so it kind of went from there my my day job as well is i guess a designer involved in high level r d and all that globally so um i have a fair idea of what's involved in making things or what parents are about or you know what to tell you guys about you know parts of interest and all that so um look it's going to be an interesting journey and we'll uh we'll have a good chat about about everything so in a normal engine the valve is controlled with the camshaft and it is returned with the spring now that's fine in a normal engine because the rpm is fairly low but in a formula one engine what happens is if you use a spring or are springs you know you can sometimes put them quick so you can stack them they'll reach a certain point in terms of hertz um in terms of rpm and at a certain point they just won't function after that they'll you know they'll start bouncing and they'll do all sorts of things and eventually they'll fracture and they'll break which is bad because your valve no longer returns and your piston then will hit the valve now in formula one in about i think what was it um i think it was renault that brought it in first in about 1987. i'm not going to go into dates on this channel that's one thing you should be aware of i'm not up to speed on dates and formula one i just know the the tech um drivers i have no idea um again i'm not going to go into sizes and all that if people want sizes i'm not going down that road because it's just it's pointless in ways you know um again with all sorts of you know stats on oil pressures and all that if if you want to know all those just look them up you know switch off now it's not going to be on this video um this video is going to concentrate solely on the core mechanism and what it looks like what it does what happens why it needs to be there again this is an extremely rare part i don't think it's ever been shown in a video before so um you know it's it's enough to to discuss that alone so when a formula one engine in as i said in the late 80s they came up with did they ditch the springs and they came up with um a pneumatic return system now this item here is is a cosworth item and the cosworth item is called the pvrs which stands for pneumatic valve return system so it's you know in terms of many of the the honda guys watching this will recognize that it's got a finger follower you know um now the volkswagen guys are the the bmw guys the later are the earlier bmws and and volkswagens had a hydraulic tappet or solid tablets even going back to the early got gti's had solid tappets but um they were all basically booker tappets um but the honda guys who recognize this you can see it's it's very similar you know um it's a finger follower and your normal camshaft and your your normal valve all that um your uh your shim on the top of the valve as well the lash cap that's all same so that's going to be familiar and the head of the valve of course so that's all going to be familiar to to many people uh watching this now just to explain what this jig is this is a jig um i obtained nearly all of a um tj v10 cosworth engine and i've measured the entire engine and brought it into cad in nearly every single piece it took i guess 5 000 hours nearly so what i did was i took a small bit of the cad and i replicated it in a test jig if you want now this test jig has been put together just quickly for the video you can see the caps and all that it's been line board and there's a window here for sensors to measure the valve because i want to do some tests the the oil supply is is right here on this banjo fitting you can see it here so that banjo goes in and there's two drillings across here in here into the camshaft the camshaft is is it the exact cosworth item it's hollow as you can see for lightness and it's got the dlc coating the diamond coating um for wear and so is the finger follower in fact so this is a test jig as mentioned it's replicates the cylinder head exactly and it just saves you know the cylinder is an awkward thing because you can't see different things and all that and it's just hard to see it so i'll discuss the how it's laid out first and then i'll uh maybe pause the video for a bit take it all apart and then show you the the item of interest so it's it's fairly straightforward um the the camshaft as mentioned is hollow it drives the finger follower nothing new there the finger follower pressed down the valve but in here is a little air chamber and it's like a pneumatic ram and here is the the piston you can just see it there which is also the the i guess what you'd call it the retainer you know a normal car speak and the two valve collets are there on top so that's all fairly standard again the valve is nothing special standard made by dell west they were a us company um actually i approached how when was it about seven years ago i think or eight years ago when i started i got a big interest in this because they're phenomenal bits of kit you know the speeds and all that and the the stiction and the friction and everything they have to overcome the ceiling and all that it got me really interested so i had to find i had to find out how they worked so i remember contacting dell west about i guess it was seven or eight years ago and that could i buy just one assembly you know but obviously that was a a non-runner um to barely answer my email um i contacted a few companies in the uk and i was basically told that you have no interest in you know you don't need to be buying them we're not going to talk to you so i eventually acquired one anyway um after a lot of searching i met a very nice man which i won't name in a company not in the uk i'm in him later but um i'd speak to him first because we came pretty close since so i'll see if he wants to be mentioned or not but um he was able to get me one now this item is out of a a ca the kosovo ca the cosby v8 the last one of the v8s which i think revved to i think on the test bench it was tested to oh i could be wrong 19 000 to 20 000 rpm so that's going pretty quick um now the the camshaft and all that this jig is designed around the tj which is the the v10 gosward so there's a small bit of differences here that you'll notice if i uh if i turn the the cam around you'll notice the valve is shorter and the reason that is because the tj had a what i'd call a t-shift or an i-beam head where both camshafts were mounted on like an i-beam whereas the the ca the later ca they went away from that and they went with the conventional head now in fact it was a bit like the dfv head in ways because um it was a multi-layer head where the the the finger follower carrier and all that went on separate because uh you could get at the head bolts were on the need to learn the cams so you couldn't you know it had to be multi-layer so it was an unusual way because um you know every interface you have is is a weakness and you've got tolerance stack up machine and all that but that's what they did and it was a smashing engine so who am i to comment but so just before i pause you guys and and strip this down um air comes in here on a gallery along the head so i've got a banjo fit in here with a with a braided line off it air comes in here it enters the chamber here and pressurizes the the air pressure underneath here now it's many bears it's very really high air pressure um to keep the valve on its seat and it um you can see if i turn it this way there's a little oh if you can see that there that's where all the the non-return valve is and there and where it can blast off the air um if the problem with these is it was a huge problem at the start these obviously because they have seals here oil can get past the seal and what happens then is the chamber itself can fill up with oil underneath the piston which will raise the pressure or worst case if it was full up all the way um it just wouldn't be able to close you know so they have a clever bit of valving in here that can blow off the oil if it needs to you know if it senses that there's too much oil in it um it's all done remotely there's a there's a full like a ring main of of uh airways in the engine now it's it's it's only one supply some of the others had two supplies and crazy dome systems and all that but um they were troublesome you know um in the early days when the scenes would fail i'm sure you've seen it back oh geez i guess 95 or 1995. um you'd often see a car a car engine just exploding or a load of smoke on the track afterwards and and the driver would have to pull in it was nearly always the the pneumatic valve train that failed just because it was so early you know um the ceiling was early days the technology was very new um so you know it was a huge hurdle to cross because again the speed here is is crazy and you've got you know 13 14 15 mil lift as well so it's it's it's beyond insane you know which which is why i got it so excited about it initially and so just to do a a last talk on it before i split it apart um this is a modular system now some of the the earlier cylinder heads they had this actually cast in to the cylinder head and the the i guess the plunger and piston all that would slide in the actual cylinder head but you know that was kind of back then and with casting thicknesses and all that it ended up pretty heavy by the time you've you know a three or four mil wall around all that in in terms of cast aluminium let's say whatever it was lm 25 or as the americans have 365 or 356. um so it ended up very bulky and there was also i guess porosity issues in the casting as well that if you did all these complex drillings and all that in the casting you know you could run into serious difficulty if uh the casting was porous you know and you'd start leaking air that way too so the modular system kind of got got around all that uh it made in-head machining i would say on a cnc machine a lot simpler you know they were all just modular units and they could be replaced um you didn't have to be in the head either even though the heads were banned after you know what a thousand kilometers let's say but you know you could identify an issue it was modular you could just go in there take it out and all that and it wasn't a painting machine you know it was just decade flat and and baltimore so what i'm going to do now is i'm going to pause it and i'm going to strip this and we'll get out what we need to see whatever proper look at it so i'll talk in a moment so here we are back again now as i said i stripped off the the jig the test jig i'd made so this is the unit in question so this is the the mock cylinder head here um and this is the the air supply as i said that's just in there with a banjo fit and drilling and drilling down so it's pretty compact as you can see um you know it's it's pretty tiny so it's as i said standard valve standard lash cap these would be ground they'd be set the valve off the seat they'd be checked with fielder gauges you know the crack and they'd be grounded to match to match each one um now actually having said that i'm not 100 sure if they ground the tip of the valve or the the lash cap but anyway it's irrelevant now the lash cap snaps on there's a tiny little i don't know if you can see that probably not there's a tiny little wire lock in there and it just snaps on uh once it's in place and this is pressurized it can't go anywhere you know so that's that now i just want to speak about the finger follower for a moment before i move on to that and to compare that the finger followers are hung from the cylinder head on an axle i have one here that's that's already removed so you can see it there it's a standard enough you know now the the intake and exhaust finger followers are different lens so it rides on a there's no there's no needle bearing or anything like that it just rides on a on a shaft like so that's bolted into the pocket on the cylinder head which i'll show you now you should see it there and there's very slight flats in just there to let the oil in the oil can go in past there's a very slight space there with the flat and the eye can go in and it can collect here and it oils all that so that's that's so that's lubricated again in terms of axial thrust this way there's very slight divots there which you can probably see on the light um which lets in the oil to all the oil the face but again there's no there's no side just really on these you know um unlike you know a tap at where the the cam would be offset you know to rotate the top of this these are directly in line so they're a nice item you know and again dlc coating you can probably see the tj stamp there perhaps maybe maybe not um so that's that part you know beautiful geometry you know um mind-bending geometry uh with with camshaft design and finger followers and all that because again the acceleration rates you know the rate the valve is accelerated off the seat is mind bending in farming one engine because there's so little time and you want to get it open as quickly as possible and again once it's closing you can't just let it slam onto the seat you know it has to close very very carefully you know otherwise you'll just rip the head off the valve so that's the finger follower now one last thing with these which you'll see on the head as well in an image um these are oiled with with oil jets now the oil jet would be similar to this it threads into a bore in the in the cylinder head you can see a very small hole there and the oil gel treads in there and it's angled at the interface between the cam and the top of the finger follower to keep a decent amount of oil there now on an earlier cylinder head which i found um initially at the start of all this i was searching for pneumatic systems and i found one i was emailing literally everyone in the world and i found one in donnington so i flew to darlington and i found a brian hart engine you probably remember those it was a v10 as well but the brian heart engine was quite old-fashioned actually i have a section of of cylinder head here from it um the brian heart engine had tappets like a normal a normal engine you know um it had no finger followers again you can see the oilers here they're bonded in right here with the it's probably arrowed out from that age and it aimed at the top at the interface there at the top of the tablet now the the chambers in these this was also a pneumatic valve trend but the the chambers in these the the the system i guess the cylinder system and these was an aluminium barrel that sat here bolted down here and the the the plunger the piston plunger actually ran on the wall of the aluminium it had a ptfe impregnated anodized coating inside and it was haunted a high finish but it actually ran against the aluminium now i believe i'm told from you know mechanics and friends of brian hart um he's actually dead since r.i.p brian some man um that the anodized courting war you know um it was extreme conditions as i said you know um but you can also see the air holes there as well that feed it's similar to cosworth head um and again the drilling along here that that fed the air holes now the one thing with with the drillings here when you're casting a something like a cylinder at a complex shape like that um the rule is with casting if you can help it you don't mix thick sections and thin sections because what happens is the thick section will cool last and when that happens it tries to suck when it cools it shrinks and it'll try and suck material from the thin sections so what happens is if these have solidified it obviously cancer computer from there so it'll actually just crack and it'll it'll stretch crack if you want contraction cracks i guess we can we can call them um so they were brave putting a drilling through that's quite a heavy area there you know there could be a lot of porosity there now i didn't you could polish it if you wanted to and get in there with a magnum fine glass to check for porosity but um normally in conditions where you're drilling a heavy area in a casting you would line it like you know with the like a hypodermic tube you know that would uh get rid of that issue um i think it was a big problem early on before the the cause cast cylinder heads came along um where the porosity was you know causing them to leak oil i i can't remember exactly what happened but i think they were leaking oil into the waterways or something like that through the heavy areas that had porosity but um that's what happened there you know but um obviously it look it it worked anyway you know um but um it was similar into the drilling as well because the cylinder heads i think we're 600 mil long so that is that's that's some drilling like you know it's it's not a core it's it's an actual drill way so um that was a fairly tense for the machinist i'd say um is there anything else worth mentioning on this they're again they said holocam chefs you know um they're oiled these were oiled from the uh the top journals and it just spread out there you know this that's elementary enough stuff um but uh yeah that was the brian hart head so i mean in fairness at the time it was amazing you know um it also had the compound valve angled um they were splayed in both directions where the the cosworth hasn't it's just played off to the vertical whereas this was played both ways which made fairly interesting cam lobe angles um so i didn't or i wouldn't pity that that cam grinders job um but again it was of its time you know it was a very nice casting um so that's enough of the the brian hart head uh we'll be back to the the cosmos one here again so what i'm gonna know is that i'm going to strip this down it's again very simple so as you would a normal engine um you'd normally have a i guess a collet pliers or a you know a valve spring compressor or a drill press depending on how stuck you were but if i just press that plunger down so that's the plunger down and the collets should come out now that's one that's the second one and i'm going to take off the the lash cap so i'll just leave those there i'll just give you a close look at those hopefully it focuses they're not nothing special you know and they're single groove they're very light uh i would imagine they're steel or some sort of very good steel i'm not going to go into specs because there's too many um so you can see there then that's what it looks like um pretty basic so far um now what i'm going to do is pull out the valve so i can push that down all the way and just remove the valve like that now the valve is very light if you've never seen from one valve every valve you've ever seen after this will look like something out of a tractor or the titanic i'm not sure that it valves but i don't think it had but it's extremely thin and it's wasted down then to i think 4.3 millimeters um so yeah they're extremely light and a nice item you can see that's the ca valve there you can you can maybe see it on the the front there see there somewhere on the left hand side um again you can see the ring for the the lash cap you can probably see it there so that's the valve nice item um it also has a there's probably a technical name what i call it a turbulence groove just just on the face see the ring around there um without getting into aerodynamics and all that craziness to do with cinderella reporting we'll leave that for another day uh it just creates turbulence at low lift so that's what that ring does it's very slight maybe 0.3 mil high and maybe a millimeter wide so they're quite big valves they're i think 40 mil diameter or something like that um so uh yeah that's the valve standard enough nothing too crazy about that we'll leave that there for the moment so removing this i just push the the plunger out of the way leave that there for a moment and that so the body is hollow um they've machined it from aluminium it's probably seven series i would imagine or seven or two series probably seven um aerospace aluminium as they call it on the internet although i think that's probably six series they're getting sold but anyway um so it's a nice part it's probably a five axis part there's a lot of machine work and there doesn't seem to be any interruptions so i would imagine it's probably done all in the one fixture you know on a five axis looking at it um on the bottom where the valve comes through this is its own valve guide by the way a tiny item you can just see there i've pressed in i actually got that as well with with the the system so i pressed that in there so it's his own valve valve seat our valve guide sort of say so that's normal enough so this ring there's actually an o-ring missing out of this i should have brought it i forgot and there's a very small o-ring that goes around the outside of that so that seals down there like so and this then would seal the top of it and the o-ring would seal both so if i remove that and put it in here you'll see where the o-ring groove is so you can see where the o-ring grooves on the outside and on the inside there's a a seal it's a spring energized ptfe graphite filled seal now it's not unlike something off the shelf from parker hanafan or something like that um there's nothing too special about that you know from feeling it and from i i i had spare seals and from burning it and all that and analyzing it it's like it's doctored graphite probably i don't know 25 30 percent um and it's just interference fit in there and that's that seal so that's the main air seal on the bottom so if you shove that on there that's your air seal so that's one seal all right so i'll take that off for a moment so you can see the air entry port here it comes in from the banjo fitting and it's drilled down into the cross drilling and that enters here on this side here and there again there's a smaller lowering in there hopefully that focuses should do and uh the air enters into the main body now again there's crosstalks and all that and this there's a lot of stuff going on in here which i'll speak about again um there's a pressure or pressure release valves and pressure pressure valves and all that for the entry pressure but um just to see how it works or what it looks like should i say um it's a basic enough part so the air enters then in here hopefully you can see that there's a very small hole just on the inside there or the air enters the chamber um so that controls obviously that's that's the main pressure and again there's a second hole um there's an air entry and an air exit or an oil exit you know because uh when it fills up you can see the entry is higher up and the exit is is there i might have got them wrong a minute ago but um basically it can purge the oil out and it blasted away out this hole here and it keeps everything in check now getting back to the brian hart system for a moment i said it was just an aluminium cylinder and with the ptfe impregnated anodized they went for a different route here which is it's somewhat surprising now i read a magazine article on this engine a while back the ca engine i can't remember who's done by i won't name them but um i i honestly can't remember and i knew there was something i missed because number one i knew casualty wouldn't give them all the parts for the photo shoot because these have never been seen before and when i looked into the bore it just seemed a bit irregular now you'll see why i i spotted that in a moment and i knew it wasn't the whole truth um there's actually a steel liner in the aluminium part in this now i'll take it apart and show you that um the steel liner is very very thin it's shoved in and it's held on with a top hat which is then bolted down through so it holds everything so if i take off this top hat now and just twist it off hopefully it should come off so there's the top hat that holds the liner in um it's a titanium part and uh it's a pretty simple but vitally important so i'll leave it there at the moment now you can see the the step on the liner that it keeps the liner down you know now i guess they went to this for many reasons um you know surface finishing is a bit more well understood with steel with tool seeds and all that um it's pretty bulletproof you know um you can also do you can probably see i don't know if you can or not you can see the there's like a cross hatching on it it's hard to say you may be able to see when i remove it but um there's a cross hatch on it so you can you know you can feed the seal with enough oil or as much oil as you want depending on how deep your cross hatching is and all that like like a cylinder bore um but this thing is pressed in now hopefully it should remove with a bit of force it's in which is very slight o-ring um so that's the liner again it's a very thin i'm guessing by feel about 0.6 mil 0.5 mil um it's a bit of a chamfer there to guide it in and the reason there's a chamfer there is because there is another o-ring there that seals it into the aluminium part which you can see there now in the magazine article i looked at it that's what i was looking at and i thought to myself hang on a second how is this going to slide you know up and down there and passed a seal and all that and it just didn't make a lot of sense so i knew it wasn't the whole picture so it might have been a few um secret spies or readers fooled with that article but um i'm glad i i found it there was a liner you know so that we all know now but um that's kind of that part um yeah it's a nice part you know um again there's there's well in the in the the v8 you know there isn't as many seals but you know a v10 you can multiply like there's one two there's three on the piston four on the top stem five here you know it's it's 50 seals that all have to seal straight away you know without any of the ancillary seals on all the other air supply stuff you know um you can see there again there's it's stamped you may be able to see it ca the lighting isn't great but um it's there on the side so that's that now the most important part which you and i will call the retainer i guess um now this also has a seal on it obviously for sealing in the in the liner which fits in there nicely again this part is aluminium uh seven six two or seven series it's a spring energized seal now looking at the parker hanafan catalog at first glance it looks the same as an off the shelf seal you can see this cross section of the seal there should be there on your screen um but i noticed with this it's got very slight and they appear to be machined afterwards pulse machined it's got very slight divots here i hope you can see that just along the the perimeter on the top now i'm guessing that's to let in a small bit of oil down into the i guess the secondary seal so it just keeps it keeps it happy um so that's that's that seal you know um nothing again nothing mind-bogglingly crazy or anything like that just a normal enough look and seal you know you may see one like it in a fest in a festo um pneumatic round or something like that but um nothing out of the ordinary and again on the inside there's just an o-ring in a groove there your standard machinery handbook o-ring spec groove and an o-ring um which seals the stem of the valve which uh again is a high pressure air seal you know um so that was i remember when i saw this first it was like amazing to see all these seals and how they did it and it was like my god it's it's amazing but yet it's it's so simple when you actually see it um but of course it's not simple at all there'd be hundreds of thousands of pounds of development behind all this you know for many many years with many engineers but um hats off to them um so that's that's that part um now what i may do is just pause for a moment and grab an allen key and pull out this and have a look what's in there so i'll uh talk to you in a sec so i got the uh release valve loosened careful not to lose anything on this now it's quite small just push those over there for a second and this should just tap out so the release valve as you can see is a spring it's held in with this little uh set screw which is uh keeps that under pressure you know now the the tip of the the plunger it's like a silicon bronze or aluminium bronzer or whatever you want to call it and it's got a ball bearing then pushed into the top just so that it doesn't erode anything like that there's also which you won't be able to see i suspect may come out no that's going to stay in there there's a very small little bronze seat as well in there that the ball bearing sits against um just again for you know this this this would hammer on that at times you know so it doesn't erode it away so it's just got to be a bit durable in there um so that's how that works it's pretty simple you know it's just a simple pressure release valve um the the the venting actually happens as well through this i'll explain that well actually what the probably the best thing you could do is is log on to f1 technical and read um read the full write-up because there's some parts i'm going to miss in this or they're just going to be too boring and to go through which are all in the article um it's not a plug for an article it's just if you're interested go on there it's called i think it's called pneumatic valve assembly a closer look or something like that you'll find it so that's that's how that works now there's another one in here as well which i'm not going to open it's the same thing but it's in with loctite you can see the grub screw there on the top which is the the feed in so that's that let's in the air if it's too low and if it's too high this one lets it out so it's pretty simple you know so that's how that works so if we take a look at i took an impression of the the tj cylinder head um it'll just give you a rough idea of what what that looks like what the ports look like and all that you know and the spark plug location uh where this would all sit i just assembled it briefly um well yeah i can assemble it yeah just very quickly just to give you an idea of how it'll all go together um that will go in there this would fit in here and my plunger is here actually i put it together this way like so that will go in there i have to put it together this way upside down because uh the valve stems don't go all the way through the silicone model so so it would sit like that when it's in the engine it'll just sit above it the valve the valve guide is quite short so in the engine it'll be like that you know um this is the intake side so it will be canted over it you know 45 degrees or 90 degrees depending on how you're looking at it but um it would sit there pretty happy this way and again these all drain down where these exit here did they drain out you know um so that's that's how that would sit and again the the finger follower would be above above the valve here and all that um actually i must lay out the finger follower just that you see it just before we call this video to an end um that would be like that this is a section of camshaft from the tj that i caught i had spare camshafts so i cut up one into sections um just to display it a bit nicer um there's some amount of duration someone who lifts as well um if you if you can see the bass radius compared to the lift you know it's quite enormous um so this will go in here like that that will bolt in cylinder head let's sit there um what am i doing so they'd all sit like that um and that's pretty much it so that is how that assembly looks like how it works how it goes together um again never been seen before it was a an amazing surprise for me to take it all apart to i guess get my hands on it first um and to show it to whoever is interested i guess um you know i i know i got i remember when i launched the the article on it um it got a huge amount of traction i was getting an awful lot of messages about it and all that from everyone from students to engineers and all that you know um so it was very exciting and hopefully we'll see the return of high-speed engines again um but we may not um with the with the new turbos and all that hopefully it never goes electric fully but um that's that so stay tuned for uh more videos on this um i'll probably do one on i think i'll do one on torsional vibrations on the valve train um in say another week or something that every other week um with the uh the dampers and all that on the the gear train up to the head so that's going to be fairly interesting um just one last thing before i finish up uh to compare the uh the height of the um the cylinder head which you know it's it's not a great comparison but it'll give you an idea you know just the sizes and all that you know you can see it's they really really made it small um so yeah that's that thanks for watching and uh give it a like give it a share send it to everything or just lie back and listen take care folks

Channel: Brian Garvey

Views: 9,120

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Id: pZGhG_431nI

Length: 41min 47sec (2507 seconds)

Published: Fri May 07 2021