Small Block Chevy valve adjustment made easy

hey welcome back everybody today we are going to talk about valve adjustment on a overhead valve hydraulic type camshaft now this particular engine is just a small cubic inch Chevrolet it is a small block it's 327 cubic inches and this thing is just plain Jane bone stock valve train with a mildly upgraded cam but it's got a flat tappet cam in and it is hydraulic so there's a real simple procedure if you have a really mild type hydraulic flat tappet cam this is the best procedure that I have found so one thing that we want to do is we want to look at our harmonic balancer here now the nice thing about this type of balancer and you can buy these is that it has marks on the balancer every 90 degrees and we've also marked our number one location at top dead center with this yellow mark we have a timing tab here with a zero on it here our timing tab mark is marked in red and we've got the number one piston TDC on the balancer here and we also have to have some way to rotate this so we just have we have these studs in here and we have a pry bar and we just use this to rotate the engine now what you want to do to adjust the valves is you want to bring the engine up to top dead center compression now keep in mind it is possible to have your mark on your balancer number one here at top dead center but you're on top dead center on the exhaust stroke that is not where you want to be to adjust these so this is our number one cylinder here so what we're going to do is I've got the spark plugs out of it I'm just going to put my thumb over the spark plug hole and I'm going to rotate this in normal rotation clockwise now you heard that compression if I rotate that around clockwise my mark is coming up towards my tab here and I feel compression come out of there that means that I am on when I get to zero Here I am on top dead center compression on the number one cylinder that's where I want to be now let me rotate this once more because I want to show you what happens when you're not on compression so if I go one more revolution here I'm just going to go all the way around and I'm gonna bring that mark up again and remember the cam and crank are two to one so I'm gonna put my thumb over that hole or my finger over that hole again and I get nothing I get no compression blowing out of that hole if you come up to TDC and you can't feel any compression out of that hole that means you're on the exhaust stroke so I'm actually in the wrong spot this gets a little bit misleading because if I adjust my valves here my adjustments going to be wrong so we'll go around if if that's the case you want to go one more revolution and you want to bring this around and you'll hear it again now I'm coming up on compression I'm gonna put my finger over that hole and you can hear it in fact you actually pulled the motor over because the pressures stopped the crank from turning where my thumb is here so we're almost to TDC here you can hear that compression so we'll bring this around and we'll put our mark on our wheel on our balancer right up the tab mark right there now my valves are ready to adjust so we've got our balancer on top dead center compression now the adjustment for hydraulics is what we have to do is we have to find zero lash lash is this up and down movement here you guys if you look at that you can see these rockers are loose so that up-and-down movement is lash if we try to run the engine without getting rid of that lash this valve train is going to be clattering like crazy and it's probably gonna you know damp beat itself to death so we have to go 2-0 lash and after we hit zero lasso zero lash means I run the nut down here until I just pinched the pushrod between the plunger and the top of the lifter there's a hydraulic plunger in there it has movement I just pinched the push rod in between the rocker arm and that plunger so what I'm gonna do is I'm gonna run this down a little bit at a time and I'm I can feel my last year you know some guys will tell you well what you should do is run this down too you can't spin the push rod that is absolutely wrong if anybody tells you that you should use the method of spinning the push rod to set these valves there they're teaching you wrong you just don't want to do that the problem with that is especially if an engine has been run and you're readjusting the valves some of the lifters are going to be bled down so the plunger will have movement and some of them are going to be pumped up and they don't have any movement so if you use the spend method some of them will actually be tighter than others so you don't want to do that what we're doing is we're getting rid of that lash of that up-and-down movement so I'm gonna rotate this and as I rotate this and tighten it I'm you see I'm pushing the push rod up and down now my lash is diminishing it's getting a lot less I got just a tiny bit left now but I still have some I have to go until that lash is gone so we're gonna go a little bit more hair okay so we're really close right there so right there I have zero laughs there is no movement up and down in that push rod you see we haven't done this one yet we got all kinds of movement over here on this one but this one is at zero lash once you get to zero lash now we have just gotten into the plunger in our hydraulic lifter down here now we have to preload that pre-loading is gonna put me down into the travel of that plunger that plunger has about 50,000 travel in it and it is its hydraulics so the valve train rides on that cushion of oil what I need to do is I need to get down into the travel of that plunger so in this case we're just going to go another half a turn and what that has done is that has put me down into my plunger I'm not bottomed out I have a little bit of movement here so I'm in the travel of that plunger right about in the middle of it and that valve is adjusted I do the same thing with this one I'm gonna go down and I'm gonna feel my lash up and down movement I'm gonna go until I get rid of that lash which is right there no I still have some be careful because sometimes you can put the socket on here and if I feel this right now if I'm pushing down on this socket too hard it feels like I don't have lash that can be misleading because if I take it off it's like oh man I have lash now so when you're checking this you might want to pull your socket off there just to make sure that you're not getting a false read by holding that socket down there so just got a little tiny bit more here just just to barely feel it okay I have a little bit still a little bit more see I'm going a little bit at a time now I just got rid of that lash I have no up-and-down play and then I just turned that a half a turn those two rockers are adjusted on a hydrolic forever you'll never have to readjust those again now we have a firing order on this engine so the firing order is one eight four three six five seven two these cylinders it's a v8 they are going to fire 90 degrees apart so after this cylinder is at top dead center compression boom it fires the next one in the firing order is going to fire 90 degrees later in the rotation so what's nice about this balancer if we take a look at our harmonic dampener or balancer here this is an aftermarket balancer and it has marks every 90 degrees so if I keep going clockwise and I rotate this engine and I bring my next mark 90 degrees away up to the zero that is going to put my next cylinder in the firing order at top dead center compression and then I can go ahead and adjust that so the next one in the firing order is number eight so I'm going to come over here to number eight and I'm just gonna rotate the crankshaft clockwise till this next red mark comes up to my top it's on I'm gonna put my finger over the number eight hole so you can see what we're talking about so here we go we're gonna go 90 degrees to the next cylinder you hear that I'm coming up on compression I can feel the compression there so my red mark here I'm just going to take and line that up and now my number eight cylinder is on top dead center firing I just go zero lash half a turn on both of those and they're done after that I rotate my engine again and I go to the next cylinder in the firing order which is numbers four so you just go through the firing order going 90 degrees at a time and you can go to zero lash on each cylinder and your vowels are adjusted now that's one method that we have if you have a a roller cam like a big roller they usually have a really small base circle and this valve adjustment method a lot of times can cause you problems you if you do a big roller cam with this valve adjustment method that I just showed you a lot of times you're gonna have rockers that are not adjusted properly because you just the base circle is just too small on those big cams and you really can't get on it using this method so we have another method we've already got number one adjusted here but we'll use it as an example anyway so what we're gonna do here is you're going to do your intakes and your exhaust separately from each other now we're still going to use the firing order method still works pretty good there's a couple there's a couple extra steps here what I'm gonna do is I'm gonna rotate my engine and normal rotation clockwise and I'm gonna watch my exhaust so this is my exhaust valve now as soon as my exhaust valve starts to open you'll be able to see it right here I'm gonna rotate this and as soon as that rocker starts to move that means the exhaust valve is opening watch right here okay so that exhaust just started to open my lifter just started to come up here and I just started to depress that exhaust valve once the exhaust valve just starts to open we're gonna adjust the intake on that cylinder now you can still go through the firing order and do this what you do is you adjust the intake here and then I go another 90 degrees and I have to watch my my exhaust on my number 8 because that's the next cylinder in the firing order so if I if I keep going what I'm gonna see down here now my exhaust over here just started to open so I'm gonna adjust the intake so you can go through and do all of your intakes in the firing order just watch the exhaust valve as it starts to open and do the adjacent intake and go one eight four three six five seven two now for the adjustment of the exhaust valve what we're gonna do is it's a little bit different we're gonna we're gonna get over here to where our intake opens so we'll watch our number one here now if you look at this we just came out of overlap my intake is gonna open if you watch this intake now we're gonna open that intake all the way so here it goes there it goes it's going down my lifter is rising here we're gonna go all the way down on our valve until where the valve is fully open when that intake just starts to come back up it just starts to close we're gonna stop right there that's going to put us on our base circle for our exhaust so if you watch our intake here it's it just started to come back up so the lifters going down so as that intake just starts to close we're going to stop and we're gonna do our exhaust valve zero lash and half a turn now same thing guys you can go through the whole firing order and do that once I get this adjusted I can keep going and I can watch my intake over here on number eight and it is still opening I can see the lifter coming up here it's going to open all the way now it just started to close so I'm just gonna go and do my exhaust adjustment on that one right there one eight four three six five seven two and your valve adjustment is done now there's one other thing I want to touch on here real quick just to give you a visual what I want to do is I want to show you a solid lifter valve train all right so now when we get into these really radical valve trains and we have we have solid lifters what we want to do you can use the same procedure that I just showed you as far as the intake the exhaust valve just starts to open or the the intake just starts to close you can do it that way but we actually have to set lash here we have to have some lash because lifters are solid it's a solid piece of steel so we're gonna take a fuel gauge we have a specified amount of last year now these rockers on this engine have already been adjusted when you get into like really hardcore engines that have crazy valve trains and big horsepower you're gonna have last year so you can see we've got that's our specified lash we've got last these are already adjusted and they're actually a little bit loose they'll they're gonna clatter a little bit you'd hear that clattering that's because it's a solid valve train they're a little bit noisy when they run that's just the nature of the beast so just remember a solid valve train has a specified lash in the valve train and it has to be set with a set of feeler gauges

Channel: Myvintageiron7512

Views: 576,002

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Id: ULA3GNHI49Y

Length: 14min 51sec (891 seconds)

Published: Thu Mar 26 2020