Why the Honda K Series is the Best 4 Cylinder Engine

today we're going to be taking an in-depth look inside of the honda k-series four-cylinder engine we're also gonna be taking a look at why honda's still using this engine today almost 20 years after his debut but more so why enthusiasts are also after this engine for aftermarket builds and just like that the engine and transmission has been removed so here's the engine out i've also removed some of the accessories in the cover the next thing you need to do is split the engine in the transmission and put the engine on the engine stand we're going to start by taking a quick look around this engine here starting at the throttle body now this is a drive by cable setup because it's an older engine that'll feed air into this cast aluminum intake here that'll push it into the engine now the top of the intake here we have the fuel rail and its fuel injectors because this engine is port injected only now the top of the engine underneath this plastic cover here is where the four coil packs and spark plugs will reside and this famously shaped oil dipstick along the side of the engine we have our accessory hookup the alternator would be here and the ac compressor will be here while the power steering pump would be at the top with one big long serpentine belt now from the back here you could see underneath the crankshaft we've got a timing chain cover that means there's a chain that's driving these unlike the older hunters that used to use a belt at the back here we have the exhaust manifold now newer k series that actually integrates the manifold into the head itself so you don't have this piece the catalytic converter will just bolt right up to the head now this engine also has honda's iv tech technology which is going to combine variable valve timing on the intake side with vtec on the exhaust side in order to vary the timing and lift i'm taking a look at the back half of the engine here this here's the flywheel where we bolt up to the transmission as well as an egr system that's right they still use egr on one of these i'm actually going to start disassembling this engine from the oil pan because i need to hold the crankshaft steady in order to grab that crank bolt and the flywheel bolts loose let's come in with my wife's old shirt here to clean up the fluid mess unlike a lot of newer engines this k-series still uses a steel oil pan so we're going to go ahead and remove that first now the interesting thing with this oil pan is that it's slightly tilted down away from the drain plug over there and that's because the whole entire engine is actually slightly slanted when installed in the vehicle because it's so tall it can't fit under the hood now the k series has a mechanical oil pump but instead of driving it directly off of the crankshaft like a j series v6 they put it down inside of the oil pan that's why the oil pan is so deep because it integrates this oil pump inside of here it's driven off of the timing chain over here from the crankshaft and also integrates the oil pickup tube i'm going to start by removing a couple of these oil pump bolts here i'll just try to wheel this off here okay oh there's gears inside so the oil pump housing is actually this part this big part of the back here is actually the balance shaft so you can see them rotating in opposite directions all right so i got something jammed in the crankshaft and i'm going to try to break this 19 millimeter crank bolt loose here oh finally and i can remove this pulley this will allow me to get the timing chain cover off there's no thread lock in this bolt so with the engine locked up i'm going to go ahead and remove the 12 point bolts that go to the flywheel here and with all those bolts free i can remove this flywheel maybe not and with that i'm going to take a pause on the bottom and flip it over and work on the top end if i got a bigger oil leak here i'm going to use my wife's vest here to clean this up so with the engine back on the top let's start by removing some of these accessories so the front here we have the air intake plenum connected to the throttle body got a bunch of cooling lines here to remove and some wires disconnect that and remove the throttle body now taking a look at this throttle body we do have two coolant lines that go in there your throttle position sensor over here and of course the mechanical linkage for the throttle cable now one of the problem spots in some of these case series is the idle that tends to fluctuate and that's due to the idle air control valve you know when that clogs up you're going to have issues with idling i've got another video on how to open this up and clean it up so make sure you check that link in the description below alright so with this wire harness kind of freed up and out of the way we're going to take a closer look at some of the emissions components on this half of the engine here now over here we've got the egr valve which is going to recirculate exhaust gases directly from the head back into the intake it's all kind of integrated in here now this was a weak spot on some hondas because this valve would either clog up or stop working causing issues with idling or even surging now i've got another video on how to remove this and clean it up so make sure you check that out linked in the description below now over here we've got the evap solenoid and the tube for it over here we've got your valve cover ventilation and this little oil catch can over here that's going to feed your throttle body with oily air now the upper radiator hose also ports in through here and comes out the back here to the heater core you can see it also passes through the egr system to kind of cool things off and i'll just pull off all of these hoses here and remove that little catch can all right this whole thing is kind of held on with a bunch of 12-millimeter bolt and just break that through so i'm going to remove this little cooling port here from the motor all right and now i can pull off this egr tube here you can see it's actually a central location for the coolant to pass through as well as the egr gases to pass through inside of here this one's got a little bit of carbon built up but sometimes these can almost get completely clogged up and mess up the system and give you a check engine code now the cooling system on the k24 is pretty straightforward we have the thermostat located down inside of here and then we've got a line that draws off of it that brings it over to this little central location over here and also feeds the heater core we've got the upper ear hose of course it's going to plug in here as well as the block directly inside of here there we go over here this looks like another ventilation valve here that's going to feed your air intake as well as the air intake up inside of here what is that now unlike the plant that was in front of it we've got the secondary lower platinum here that connects it to the engine further at the top here we have these injectors that will sit right on top of the air intake now this is a port injected engine which means that the fuel is injected in the air stream before it goes down into the combustion chamber later versions of the case series did include direct injection go ahead and loosen up the fuel rail now i can lift off that fuel rail and here you can see those four injectors all right and with all the bolts and nuts free i'm gonna remove this air intake platinum now we're gonna take a look at the top of the engine the top cover removed i found that there was no bolts holding these ignition coils down so that could have been causing that misfire now the k20 uses a coil on plug design which means that you don't have a distributor anymore that you had in the earlier honda engines i'm just going to lift them up here and start disconnecting them and i can pull this harness out of the way next we're going to pull off the valve cover now there's only a couple of bolts holding this on and that's probably the reason why these hondas tend to leak these valve covers as you can see here there's so much oil build up and lift off that valve cover here's what it looks like with the valve cover removed on the k24 first thing you'll notice is how tall its overall profile is that's because the camshafts sit on top of these rocker arms which have to push down on the valves inside of here rather than having a direct cam bucket design now here we could see what honda calls iv tech which is intelligent vtech it basically combines variable cam phasing with this phaser over here with the vtec system which has a different cam profiles i've got videos on both variable valve timing and vtec itself so make sure you check those out in the description down below now because this engine is out of a regular hot accord and not some type s performance model this actually uses the economy version of vtec first of all that means that you don't have vtec on the exhaust cams and you could tell because you've only got a single cam lobe for each pair of exhaust valves now over here on the intake side of the camshaft we have these two cam profiles they correspond to these two rocker arms and valves respectively now this larger one here is what's going to power this one at all times whereas the smaller one here actually does not have a profile to it it's just a complete circle which means that this valve is going to stay closed most of the time that is until vtec engages a pin is going to lock these together and then they're both going to follow this taller profile so effectively when you're at idle or low lows before vtec kicks in you're only going to use one valve per cylinder for your intake side it's only until vtec kicks in you're going to use two valves now that's opposed to the performance version of vtec we've got three lobes and the two outer lobes are going to feed the valves most of the time they're always going to go and then the third one is the larger lobe that's going to engage when vtec engages to give both of them even more push now honda's chosen to do this because if you've only got one valve at lower rpms then you could only restrict the amount of air and therefore increase the amount of mixing of fuel inside of the combustion chamber which is going to increase your efficiency now of course there are performance versions of this k series engine that are also going to use cam phasing on the intake and the exhaust side as well as vtec on the intake and the exhaust side and those engines are going to give you much more power than this economy version now the water pump is luckily driven by the accessory belt they're going to first start by removing the pump itself what do you think that's shaped like now the k-series uses a plastic thermostat housing just three 10-millimeter bolts that hold it on and here's what the thermostat looks like i'm going to remove all the nuts that hold this water pump housing on and you can see it also looks like it has some oil passages inside here for the pcv system now this here is the valve that controls the cam phaser called the vtc valve and sometimes some hondas have issues with this guy it's either be cleaned out or replaced we've got another video on how to replace this on the vehicle so make sure you check the link in my description below next i'm going to remove all the bolts holding this timing chain cover on all right with all the bolts removed i'm going to pry off this timing chain cover here with the timing chain removed we can have a closer look at the overall profile of this engine you got the crankshaft over here and it feeds the oil pump at the bottom here and then way up at the top here we have the intake and exhaust cams so you can really see just how tall the overall profile of this engine is we've got these plastic timing chain guides over here and the tensioner located over here i'm going to start by knocking this tensioner loose here so we can release the tension from this chain and a couple more bolts and then i can remove this now the k24 has got one more slide at the top here between the two cams and then once that's done i can work the chain off just like that next up i need to remove the valve train at the top here now there's lots of 12 millimeter bolts i'm going to start removing slowly pry up on these cam covers here and i can remove them all right with those out of the way i'm going to remove the cam shaft the intake side and the one on the exhaust side all right now i'm going to remove this assembly here carefully because there's pins inside that could drop now because the vtec is only a two rocker system there isn't that third extra spring that you would have in the middle for the third rocker the way you would for a performance version of vtec remove this exhaust just pull off that exhaust header at the back here we have the vtec solenoid and there's the vtec solenoid now this gasket here is known to leak so if you've got a honda you definitely know what this is next up i'm going to remove the head bolts now these are 12 point 14 millimeter socket i've got it on my breaker bar here all right now i'm going to pry up the head here should be able to lift up the head there we go now taking a look at the top of the engine you don't really see any failure or anything this engine was definitely broken in it's got a lot of carbon build up on the top here but other than that it looks pretty healthy i'm going to remove these oil baffles from the bottom here just a couple of 10 millimeter bolts next up i'm gonna knock through the connecting rod bolts and i'll remove the connecting rod caps and just drop the piston down and i remove these two pistons from the outside the connecting rod bearings themselves look okay the backside just kind of worries me because the coatings kind of come off i wonder if this engine kind of ran out of oil this side's okay but this bearing is even worse all right next we're gonna try to knock these main bearing bolts free here you're gonna have to use the breaker bar the old-school way the k series engines have an upper oil pan which is this piece over here that sandwiched the crankshaft with the block there's a bunch of 12 millimeter bolts all the way around it i'm going to remove in order to pop that off the block the crankshaft wants to come off with the oil pan because of the rear main seal so now we've got this entire k24 torn apart here we're going to take a look at the individual components starting at the bottom here with the oil pump now this oil pump is chain driven and it's also got a spring tensioner here to keep tension on that small chain from the crankshaft now the oil pump is only the front housing here the shaft is going to extend back into these two balance shafts here that spin opposite of each other when this rotates now these two shafts have these two weights over here that are going to oppose the motion of the pistons moving up and down so they cancel each other out to make your engine vibrate a little bit less it's going to remove some of these bolts here so we can take a look inside i'm going to crack this oil pump open here there we go let's take off the gear then i can pop off the housing here now taking a look at the oil pump we've got oil that's going to be drawn in through the oil pickup screen over here and come to the low pressure side and just like any other fluid pump we have this little offset gear here that's going to keep rotating and that's going to squeeze the fluid through here to provide fluid flow and then push it out to the outlet of the housing and this is the oil pressure relief valve i'll just remove that cover oh it's got bearing surfaces on the inside just like your crankshaft and here we've got the balance shaft so you can see these are the two gears that are going to spin counter to each other and they're perfectly timed with the engine's crankshaft so they move exactly opposite of the way the pistons are moving just pull these shafts out and you can see they're just weights on the end of the shaft here now oily situations are going to call for my brother's old sock here to clean things up because it's getting really messy especially on my cardboard studio here next we're going to take a look at the upper oil pan on the k24 now in the middle here we've got the main bolts that'll hold the crankshaft in but supporting all that is this entire structure because it's also bolted to the block on the outside and that kind of lends to why this engine is so strong you basically got a ladder frame design here that's bolted to the block and the crankshaft securing everything in and that is opposed to having the individual bearing caps bolted directly to the block where it could be a little bit more weaker now the front side here we've got the oil port so they're going to bring oil up to the block there's also some block oil return ports over here i'm going to take off this oil filter here now this kind of tells you a little bit about the past owner of this car and how much they cared for it now if we take a look at the k24s block we've got the oil that's going to come inside of here and go straight to the oil filter to get filtered out it'll then get sent through this main oil galley over here to lubricate all five of these bearings for the crankshaft and connecting rods now all of these k24s use an open deck design which means that there's no reinforcement between the cylinder walls and the actual block itself and that's not going to be as strong as a semi-closed design but at least it'll have sufficient cooling around the cylinder now also on the top of the block here you can see a bunch of oil supply ports and return ports that will feed the head now if we take a look at the k24s cooling system it's pretty straightforward there's a big giant water pump housing here that's going to bolt to the block itself now also kind of interesting is this passageway that's a little oily and that's for the positive crankcase ventilation system so it's going to use these little passages instead of here to properly ventilate the crankcase but it's got this trapped design here so that it kind of allows the oil to flow back to the bottom of the block and just allow the air to go back into the air intake through these hoses if i use my brother's sock here to wipe up these cylinder walls i noticed that there's a lot of scoring up around the top area over here where the piston ring would sit but i can still see the cross hatching on the inside of the cylinder there were a number of different crankshafts for different k series engines this one is just the regular crankshaft if you upgrade to say a tsx engine it's got a built up forged bottom end and these are much stronger inside of there to handle the more power also in typical four-cylinder fashion you've got the two middle pistons that are going to move together in the middle and the two outer pistons that are going to move together opposite of those two inner ones and that's just to counteract each other with primary vibration force now the pistons on the k series did vary depending on which engine you got say if you upgraded from this support engine to a tsx these would have definitely been built up and be a lot stronger with lighter weight pistons this piston's in okay shape it's got a lot of carbon buildup on the top but other than that i don't see any extra wear marks especially on the sides here now of course on the k24s the strokes are much longer so your pistons are going to be a little bit longer on the k20s though the bore is actually equal to the stroke so you've got a square design which is going to give you a good balance between power and torque now if you look really closely you can see the oil control ring which is this third ring on the bottom here and slowly getting clogged up now on the newer k24 z engines and the newer records these oil control wings had a huge issue where they would clog up causing excessive oil consumption that oil control ring is there to scrape any oil away from the cylinder wall as the piston is making its way down now when that oil control ring clogs up the oil has nowhere else to go but in the combustion side and get burned now the only solution to this is basically take out your pistons and clean up or change these rings completely or swap in different pistons with a better design next we'll come to the most debated topic on any k series engine and that is the head now this is a k24 a4 head which means that it's just out of the regular accord now this is a port injected engine which means that we've got gasoline that's going to come into here and that's why this intake and these valves are so clean there's no carbon buildup of course the newer k series engines are direct injection only which means that the gasoline doesn't pass through here and you can get carbon buildup on these valves now this head design is a good example of where honda went to the extensive engineering something very different than a typical four-cylinder economy engine now on regular four-cylinder engines this camshaft here is going to sit right on top of these valves and each cam lobe is going to directly drive the valve now instead what honda has done is they've put this on top of this cradle over here and this cradle is going to house the assembly it has a roller rocker arm system now you've introduced a whole bunch of other mechanical components that of course make the assembly a lot bigger now these roller rocker arms are what's going to follow the camshaft profile and then press down on the valves indirectly now although they've introduced a lot of mechanical complexity with all these extra moving parts hondas still maintain this to be a very reliable design the only thing you need to do is periodically adjust these valves every so often so that the clearances between this and the valves don't give you that tap tap tap tap noise of course the reason they've done this rocker roller arm system is because of the vtec system to allow different cam profiles if you had this directly driving each bucket then you couldn't switch profiles to give you extra valve lift now to further add to the complexity of the vtec system honda's added variable valve timing to the equation here so that means that this head has a lot of oil passages in it we've got the vtc solenoid that's going to plug in over here and give control to this variable timing gear on the intake side then we've got the vtec solenoid it plugs into the back here and that also has its own oil passages that are going to feed this assembly here to engage and disengage these roller rocker arms to follow the higher cam profile now as i mentioned before there's two cam profiles one for each valve on the intake side on the cylinder we've got the taller cam profile here the shorter one actually does have a peak a very slight one in this pot over here so essentially this valve is going to open very slightly and a little bit earlier or later because the peaks are actually offset in the rotation of this camshaft you just kind of find it weird why they would put security bits on the variable valve timing gear anyway some hondas and toyotas suffered from these variable valve timing actuators rattling on cold starts i've got another video linked in the description below if you want to check out the reason why that happened now some people have noted that the k-series exhaust camshafts tend to wear out a lot and that could be due to a worn out rocker that starts eating away at this camshaft causing a ticking noise from the top end of the engine and of course we come to the infamous vtec actuator now most of the time if your vtec is not working or if you got that pesky vtec code it's probably due to this thing over here which is the solenoid that controls the vtec system and the oil pressure switch to make sure that you've got enough oil pressure to engage vtec now since this is one of the earlier k24s it's got individual ports for the exhaust newer ones integrate the manifold into the head itself so the catalytic converter bolts right up to the head itself now some tuners argue that this head is the one to get because it's gonna flow a little bit better than the one where it's all integrated into the head now there's so many different heads that you can get for a k series motor the most common one is to swap on a k20 head onto a k24 block because that's going to give you taller cam profiles stiffer springs better intake and exhaust flow so it's definitely worth the upgrade and because parts are so easily available and easily swappable everything is compatible with each other it just bolts right up that's what makes the k-series so good for tuners and people who like to modify and tinker with their cars now the air intake system on this k-series engine is actually quite complex considering this was in family and economy cars almost 20 years ago when this engine debuted now of course you've got your four ports over here that are going to feed air to the cylinder heads but we've also got this additional valve over here this is called your air bypass valve it's going to take air from the air intake tube and bring it around over here to feed the injectors that's right it means it's actually going to feed the injectors over here through these small little holes with extra air so that it mixes with the gasoline so you get a little bit of a leaner mixture especially on cold starts to help you warm up now this valve here is actually sitting inside of the coolant jacket which goes into the block from the thermostat now when this does warm up and coolant starts flowing through the engine it's going to shut off the flow of that to stop the air from being so lean in addition to all that we've got the head and the intake manifold that supports the egr system now the egr system is going to take exhaust gases from this bottom half here and bring it through this port and the egr valve itself is going to control the amount of exhaust gases that can come from the head and go back over onto this port over here then through this port over here then into the air intake and then once it's in the air intake it's going to follow this track at the bottom here to go into this port over here to get distributed into each one of these intake ports over here to get re-burned now one of the things with this egr system is that all of these ports here and the valve itself do tend to clog up with a lot of carbon deposits you can see if i use my wife's old toothbrush here just how much of this stuff can just flake right off at some point you're going to want to open your air intake system and clean out all these little ports now additionally the egr system must be cooled off so we've got this coolant hose that's going to run through from the thermostat through the air intake manifold and then into the head here that'll then run over here to this jacket over here which is going to correspond to this jacket over here where your upper radiator hose hooks up your heater hoses also hook up to the back here so you can see this also forms part of the coolant circuit now of course all this complexity and sturdiness with this metal design has been swapped out for one piece plastic design a newer k-series engine now with how complex this engine is i really have to give kudos to honda for making a really good strong engine that's going to last very long yet it can still be mass produced in many vehicles today such as the accord civic and the honda crv now the bonus is if you're an aftermarket tuner and you're looking into building one of these engines this is definitely a good platform to start because there's so many different variations of the case series that it's really easy to find components and swap them on not to mention the aftermarket support for these engines and that's pretty much an in-depth look at honda's k-series engines and how they work in my opinion it's probably one of the better modern engines honda has made it's just unfortunate though that it's probably going to be replaced by the 1.5 turbo l15 engines found in the civic and the cr-v now make sure you follow me on instagram for more behind the scenes footage and subscribe for more videos just like this one

Channel: speedkar99

Views: 341,050

Keywords: honda, acura, k-series, k-swap, k20, k24, inline, 4 cylinder, v6, engine, motor, transmission, drivetrain, flywheel, piston, connecting, rod, bearing, oil, valve, cover, rocker, roller, arm, vtec, repair, teardown, works, fail, problems, best, strong, mileage, turbo, civic, accord, CR-V, CSX, type R, type S, s-2000, racing, tune, variable, timing, crank, camshaft, intake, exhaust, mods, ECU, flash, hondata, ricer, replacement, rebuild, analysis, budget, EGR, idle, cooling, lubrication, inside, remove, how to, award, mount, lift, TSX, RSX, TLX, rev, RPM, kick

Id: o_hbAl3BFuE

Length: 23min 25sec (1405 seconds)

Published: Mon Dec 21 2020