Chevy Block Inspection at home

so as you can see the block has been cleaned up batted it we cleaned all the surfaces off what I have here one of the things we want to check you want to get a straight edge now this is not just some random piece of Steel this is a precision machine straight edge and this one was about 80 bucks buy them for anywhere from forty to a hundred dollars depending on the supplier but this is a pretty heavy heavy duty one pretty Precision straight edge so we want to look at the surface of this deck to make sure that it's not warped because I you know as you're well aware of cylinder heads can Warp but the deck surface of this block can also become distorted in warm so what we want to do the specification for this engine is you're not allowed to have any more than three thousands Distortion or warpage or twistage in a six inch span so we want to check this all along here with this straight edge now this has been machined so we know this is perfectly straight so this is our standard so what we want to do is we want to find a 3 000 Spiller blade which is maximum allowable and then we're just going to take the straight edge and set it flat down on here now what I do is I put the three thousands underneath and I make sure that I can't slide that under there and we want to check especially in the fire ring area we want to check around all these fire rings and in between the cylinders and we want to make sure that we can't pull that out of there all along the surface and this one this looks really good this block and now we've already checked this but I just going to show you this as a demo now what you also want to do is you want to go diagonally in this direction and what this does if a deck of this block is Twisted in this manner one way or the other that's really not going to show up checking in the center here you could pick up absolutely no warpage and still have a twisted deck so to get the Twist on the deck of a block or heads for that matter you wouldn't want to go diagonally so we're going to go diagonally in both directions and we want to see if we can move this thing in here I'm not I'm not pulling anything in this diagonal Direction here so we want to make sure that we don't have any of that twist going on and then we're going to go diagonally in the other direction and we also want to make sure we don't have any twists going on here check around all the cylinders all the way to the end [Music] and I really can't pull anything here which tells me that the deck of this block is in pretty good shape so I don't I don't really have any issues here with this block and that's that's basically how you do it in order to make sure that you don't have any Distortion or anything like that this one looks really good so we checked both decks on this thing and we didn't pull anything so once you get that checked that will tell you whether or not this needs to be resurfaced or decked we are not going to deck this block simply because the surfaces of this are so so flat not likely that you're going to have a block with this much meet up here have any kind of distortion it's possible but it's not likely okay so now we start looking at the cylinders now we've already miked all this out and we have the cylinders honed or I honed the cylinders I should say this is a dial bore gauge and I've got this set for the bore size here now the bore size on the 305 V6 is the same as a standard 454 which is 4.250 four and a quarter inch bore this block has been bored 60 over and so that makes it 4 inches 310 000. so what I did is I took my four to five mic and I set it for 4.310 and then I I went ahead and I put this in here at 4 3 10 and I zeroed out my indicator so the indicator is zeroed at what the bore size is supposed to be and then what we do is we just take our indicator in here and we can see what our bore size is so we want to we also want to check this cylinder and make sure that it is not out of round or tapered so one of the ways we do that is we put our bore gauge in here and we just put it up at the top of the board here and then once we get it centered we can go ahead and zero this out and then we run this down and we see if we have a difference between top and bottom so these are really nice straight cylinders we have no difference from top to bottom and then of course if you want to check out of round you can check it this way and this is something we also need to check and then you go diagonally in the other direction and on this cylinder we have we have the same measurement all the way around so that means that the hole is perfectly round and it's straight it doesn't have it's not larger at the top than it is at the bottom making sure that the cylinder is round and not oval shaped or oblong or tapered which they have a tendency to get bigger at the top when they taper because that's where all the cylinder pressure is those are two things that you need to check for and a lot of times a machine shop will do that they'll use a bore gauge to do it this cylinder on this engine these cylinders are really good they don't have any tape or they don't have any out of round and we hold them um for the Pistons that we got so everything turned out really nice on this motor it should be a good build but if you're if you're working on an engine that has a lot of miles or a lot of wear it would be advisable to bore the cylinder or have a machine shop bore the cylinders oversized we didn't have to do that in this case we just went ahead and honed it all right now we're going to look I want to draw your attention to the bottom of the engine so this is our these are our main caps here on the lower end of the engine I'm going to go ahead and pull these off one of the things that we need to to make sure that we check on any engine we build but we're going to check it on this one is to make sure that the main bores are in alignment what can happen over time is the main bores can become distorted in relationship to one another these bores have to be in a perfectly straight line so we have to check that so now that we got the Caps off we've exposed exposed the upper portion of our main bores here and I'll show you how we can check and see if these are misaligned so we take our straight edge and we just lay our straight edge in here and then we're going to take a filler gauge now this is the smallest feeler gauge on the set this is one thousands so what we do is kind of like we did with the warpage we just take and we let the weight of the straight edge sit on that and we make sure that this does now I can pull that out of there that's not what you're looking for what you want it what you want to do is put the weight of the straight edge on there and make sure that this thing doesn't slide easily under there and it's not sliding under there on that one if this blade slides easily under any of and you can see it's not it's snug there and we go to the next one and we have let's get this straight in here this is not sliding and then to the last one here no movement I can't slide this blade in and out I'm pushing on this blade and I can't slide it in and out I'm trying to slide it in and out of there it is not moving now again I can pull it out but that's not what you're looking for you're looking to see if I have a gap here or to see if this this blade will actually slide under here and it won't I can't push it and I can't pull it so what that tells me is that these bores are in a perfectly straight line now if these bores were distorted because these are precision machine bores just like the cylinders are they're just a very short bore now if these bores were distorted in relationship to each other in other words they weren't lined up perfectly your feeler gauge would be sliding under here and then we'd have to take the block uh set it up on a machine and a line home or a line bore this block but fortunately for us this block has no misalignment so it's in really good shape okay so another thing we want to do now that we've established that the alignment is good we want to take and put our caps on one by one because remember like I said this is a precision machine bore here now the Caps are directional and they are they are also location specific this these caps are numbered this is number one and right here it says front so this goes to the front and the number one cap here and you'll notice these notches here on most engines the notch is here and the block The Notches here The Notches are usually on the same side and that is the case with this so we're going to go ahead and put our cap on there now one thing that you need to do these caps fit into this pocket here you need to make sure that the cap is seated down in the pocket before you start tightening these bolts otherwise you could damage the cap this one when it's snug but it went in there pretty good so I don't need to tap on it and then we're going to take and we're going to torque these to Specs so the torque on the 305 is 135 pounds that's pretty significant torque so you want to make sure they're torqued correctly and to spec in other words we want to get a good reading on this bore so we're going to torque it to 135 pounds there we go okay we got it torque the specs then we're going to take our dial bore gauge again um we want to know that this is round so then we're going to take our bore gauge and we're going to put it in here right in the front and we're going to find the smallest point and we're going to zero that out just like we did remember this is a bore just like the cylinder is then we're going to go just gently slide it back to the back of the bore and make sure we don't have a difference here and we don't it looks like so the bore on this thing is not tapered it has the same diameter in the front of the bore up here as it does in the back which is good now for out of round what we want to do is again we're on our zero here and then we just want to rotate this around in a diagonal fashion and you can't see that but I'm looking at it here and we have no difference we're still zeroed out on that bore so what that tells me is that main bore doesn't have any outer round or taper and again we've already checked all these we know that the com the the bores and so forth are good on this but this these are some things that you got to check because on any engine not just this one but the main bores have to be round and the cylinders have to be round and they have to be the right size now to get the right size on this thing what you can do is just look up the spec for this bore diameter in the book set your micrometer for that and zero this out and then you can you can put this in there and check it and we've already done that and the bores are really good size on this so the bores are within spec size wise and it's important that these boards are inspect because that's what controls your oil clearance down here and also if they're out around and tapered it's going to cause rapid wear on your on your main and rod bearings your main bearing specifically and we don't we don't really want that to be the case overall this block is in really good shape if you don't actually measure all these things out a cylinder bore a main bore any of these bores that we have here they could look good visually especially after you clean the motor and do some honing and cleaning it could look really good but that doesn't mean that it's within specifications so the difference between a motor that runs well and one that destroys itself very quickly is basically is are the clearances with intolerance or do we have some wear in there so if we had wear on these bores down here we would actually have to do some machine work to a line hone or a line bore again just like as if we just as if we had you know uh misalignment or anything like that so hopefully that makes sense um so that's basically the block the block is in great shape so we are well on our way to a really solid build here it looks good

Channel: Myvintageiron7512

Views: 5,446

Keywords:

Id: GsFlgYB7pcE

Length: 13min 16sec (796 seconds)

Published: Thu May 11 2023