How to REPLACE a HEAD GASKET TORO Briggs & Stratton 7.25 163cc Engine Guaranteed to Start lawnmower

old bo cephus has had enough so check out this mower guys starts runs great but it's making a funny noise and i'm go ahead and take the spark plug cap off so it won't start but you'll be able to hear it i think it's kind of a puffing sound uh i don't know if you can pick that up on the camera but uh you know it sounds like it has a blown head gasket even though it runs perfect go ahead and start it up for you so you guys can hear it all right that's the first time i've seen that puff of blue smoke coming out from under there so now i know it has a blown head gasket also if you look i'm having a hard time seeing if the camera is picking this up or not but if you look you can actually see where the hot gases were puffing out it's leaking a little bit of oil from the head gasket under here and as i said that blue smoke that came out from under here i think it came out from under here it didn't look like it was coming out from the muffler that's a telltale sign that you need a new head gasket plus i can really hear it puffing and if you look on the deck here you can also see some oil buildup probably from puffing out of that blown head gasket so let's take this apart and replace the head gasket this is the first time i've ever done one on this style of engine and even though it runs and you could run it like that and it looks like he's been running it like that for a while it's not a good idea because that will eventually start to cause damage to your engine so let's replace this head gasket and it's the newer style overhead valve with the plastic carburetor i think they're pretty good engines so far auto choke easy start we'll see how easy it is to replace the head gasket so it looks like we need a little torx bit which is this style of bit this is a t25 size and it looks like we only have a couple of bolts to take off here let's see what happens it's still attached in front there's probably a clip up there wait a sec it's kind of squishy right there we might have to poke a hole there to get to the other one well that's how you get to the tab so you have to poke a little hole there so you can get to the tab and push it and then it comes right off see that's what it looks like this little tab right here that you just have to push back to get it to come out of that little slot all right i don't know how far we're gonna have to tear this engine down i'm gonna use my 5 16 socket on these to take this cover off here i think we have to do that might as well help us see things a little better don't lose these bolts you can see their shoulder bolts they're not cheap all right that was easy so now i think we can uh see everything anyways and i think we'll be able to get to everything i know we'll have to take the muffler off so i guess we need to do that another 5 16. bolt oops first we need a quarter inch to get the cage off all right so i have my quarter inch socket take this one off and there's also one back here and one on the bottom hi and then we have this one here just like that now with the 5 16 i think we can take this muffler off one on the top one on the bottom there we go oh this is your uh automatic choke mechanism so you can just simply disconnect it like that off the linkage i suppose we can disconnect the spark plug here [Music] all right now what do we do everybody i think maybe we should get into this valve cover just so we can see what's in there looks like our 5 16 socket will do it again here one on top one on the side one on the bottom well there we go that's what our valves look like first i'm going to put all this stuff in a little container before i lose it the old 10 millimeter all right let's see what happens i think we're also going to have to disconnect the carburetor it looks like so let's do that and then i think that thing will come off of there and so to get this carburetor off of here you take off the cover the air filter and then you have four bolts in here to remove these outside ones this is a 5 16. socket and this is a 9 30 seconds socket to get these other ones out so now you can take this part off you just have to disconnect this tube so you can see the white piece there that little white ring stayed on the intake manifold and the o-ring also came off which is right here which is right here and basically you just to put this back in right you just put the o-ring inside the carburetor and then you push this little clip in and that holds the o-ring in place so that's what that looks like when it's installed correctly and you can see it just slides on the intake manifold there i think we are disconnected now maybe yeah just gotta finish taking these bolts out here take note make sure these are the same push rods that was the uh the top one put that here for now here's the bottom one dang i still have one of these bolts in here come on you stinker looks like this is the little stinker that's holding it on there we go all right so we have the head off and both of the push rods uh are the same too and if you hold them together you can spin them and tell that neither of them are bent and it doesn't matter which way they go in either so keep these in a safe spot i can't believe this engine ran so good with a blown head gasket didn't smoke really or anything it just was making that huffing and puffing noise all right i'm back several days later and uh this is the part number for the head gasket for this model here's the new head gasket now i need to take some time and clean up this gasket surface here i have a uh brass bristled brush so it won't scratch the aluminum brass is softer than aluminum so won't scratch anything and you clean this surface up real good i also have a little bit of sandpaper here i want to make sure to have a nice clean surface and you can see we've almost cleaned up all those marks there and anything that fell inside the cylinder here you'll want to get that out and make sure to clean up the head side here so so and you can clean out the combustion chamber a little bit if you want to all right so that looks pretty good and you see this little carbon ring around here it's always a good idea to clean those up a little bit so all right so i have everything cleaned up the best i can this gasket surface there the gasket surface here and that's how we go like that put a couple of the screws through here to hold it in place hold the gasket in place now i have to figure out the uh the tightening procedure on these four bolts i'm not sure if you're supposed to tighten one down first um i'm sure that you criss-cross them when you start tightening them down i also don't know how tight to make them i need to get the torque specifications and i haven't been able to find a lot of information on this engine i ordered the manual but it hasn't come in and i'm tired of waiting for it so i'm going to try to figure this out so though the head's not on here completely tight yet i can still mount up um you know the carburetor here so let's do that just to kind of help start cleaning things up a little bit here all right that's what goes to the choke okay looks like the 10 millimeter is the one you need here so i think we can just crisscross them and we'll be all right i'm also going to tighten them down in stages about 140 inch pounds is what they recommend which is about 11 foot pounds that one's torque that one's torqued all right that one's torqued so to adjust the valves we'll need to get to top dead center to adjust the valves we'll need to get to top dead center on the piston on the combustion stroke so to do that i'm going to go ahead and push the get the push rods back in place so i can watch them move and once again they're both the same nice and straight and if you look down in here you'll see that back in in inside the engine they actually sit into a little socket so you'll of course want to make sure that they're in that little socket back there and uh now when we rotate the engine the push rods will move and we'll be able to tell uh when the intake valve is open and the exhaust valve it looks like this top one is the exhaust valve so we want to look for this bottom one moving here and there it is you want to wait until it's coming up that's the exhaust all right so now the bottom push rod starting to come up which is opening the valve so as you can see the screwdriver is moving down and [Music] now we are on the combustion stroke moving back up and we'll want to just rotate it until the screwdriver is as far out as it's going to go and that's top dead center right about there that's top dead center now we can measure these valves looks like i can get them back on here just by pushing the valves down a little bit there we go so at least they're both in position now point zero zero four two point zero zero eight uh from what i could tell is is what we need that one feels a little loose that one feels a little loose so we could tighten these a little bit let's go ahead and do that to tighten these you're going to need a torx bit and whatever size that is and the size bit it is is a t10 little tiny one so let's do this top one first and we'll just crack it a little bit and this is an eight millimeter it's a little too big but i think it'll be it'll work take this out a little bit more all right that feels about right slides in and out with some resistance tighten down this lock screw not very tight you can bust those off pretty easily and now that we're tightened up i'm going to check it again all right so i just finished up this bottom one same procedure and uh looks like we're set pretty good at point zero zero four we can put the spark plug back in i'm also going to spray a little bit of lube all through here um just to make sure while things were apart nothing got too sticky [Applause] all right back to our 5 16 here so okay all right got these all good and tight can't remember did this go over the spark plug or below it yeah i think it'll go like this so let's put the muffler on the linkage him over here i don't use my drill to torque things down because it's powerful enough it'll strip out bolt ah there we go where's that cover so okay we're good there now let's get to this other side where the carburetor is we'll want to hook up the breather tube and just mounts into place like that and these screws here go on the outside these are the bigger ones and before i tighten these down completely i'm going to go ahead and install these tighten these babies down and back to these outside ones air filter cover all right let's get this engine cover back on here pretty straight forward and these tall daddios go back in tighten these three screws down so i don't know why these guys use these damn torx screws they're just a pain in the butt [Applause] all right folks i think we're ready to test this baby out no more huffing and puffing you

Channel: Jeff's Little Engine Service

Views: 37,746

Keywords: tdc, top, ded, dead, center, senter, briggs, ohv, model, toro, craftsman, jon, john, deer, deere, poulan, troybilt, troy, built, bilt, troy-bilt, troy-built, start, stops, dies, smoke, smokes, running, when, how, what, where, look, work, wont, dont, starting, white, blue, engine, motor, lawn, mower, lawnmower, valves, adjust, adjustment, procedure, specs, specifications, tork, torque, bolts, off, on, put, take, spark, gas, fuel, petrol, scotts, lawnboy, yard, machines, machine, parts, diagram, shows, video, which, way, valve, check, test, tell, bad, fix, repair, symptom

Id: v44esT7QpOQ

Length: 29min 15sec (1755 seconds)

Published: Sun Sep 20 2020