Blown Generator Engine Rebuild - Part 1

hey guys welcome back so today i brought home this 5 000 watt powermate generator it is powered by a briggs and stratton engine and the title on this listing was free generator and when stuff like this goes up for free it goes in minutes thankfully jason from pate's performance noticed it right away and he messaged ken of ken small engine who was local to the person that was giving this away you know ken picked it up messaged me and here it is so thank you guys for that i do appreciate it anyway in the description the person who gave this away stated that the engine is spinning over freely the piston is not moving and he was able to push the piston down so the pistons not seized but it was more than he wanted to deal with so he just wanted to get rid of it anyway before tearing this thing down for parts i do want to validate the diagnosis and the engine actually isn't turning over at all now i think most likely the piston got pushed too far down and is now making contact with the crank so i need to get the carb off the blower housing off and see if i can back the engine up to see if that piston is moving and i mean worst case this is parts potentially it could be rebuilt but i won't know until i get it off and opened up so let me get you set up a little bit better and get going on this thing do okay so at least the crankshaft spins it almost makes it 360 degrees around but it does get hung up right at about top dead center so that kind of makes sense that is where the crankshaft journal is closest to most likely where the piston is or what's left of the connecting rod so i'm going to pop the spark plug out see if i can see anything but i am pretty sure that the connecting rod is blown on this well it is pretty much impossible to get a screwdriver in there or even look in there with the amount of clearance i have here so i'm going to use this magnetic retrieval tool just to put down to where the piston is and we'll rotate the engine see if this moves at all yeah we get nothing so connecting rod's definitely blown this engine has to has to come apart so before i can get this engine opened up i do need to get the stator and the rotor off and even before that i'm going to pull the gas tank and drain the oil believe it or not this engine is full of what looks to be clean oil [Applause] so it took quite a long time to get that oil out it was about 30 minutes in total and initially i was thinking maybe the wrong oil was in there and that's what killed this engine but when pouring that oil tray into another container for recycling it actually flowed quite well so i think the oil actually was fine most likely there's just some debris from the engine like engine parts blocking this passage all right now we got to get the stator off this one has the outlets built in to the end cap here and this should come off as one piece i guess first i do want to get the brushes off so we don't damage them and then there's two bolts holding the stator down so i'll get those loose we can lift it up slide a piece of wood to support the engine and then remove these four bolts going around and the stator and outlets should slide off as one unit all right so now we got to get the rotor off and my usual bag of tricks aren't going to work with this powermate setup there's a few reasons for that but usually what i do is i put threads here and cut a rod to slide down the shaft which will push on the crankshaft when the bolt is tightened down but in this case the diameter here is the same as the bolt and for this to work you really need to put a rod that's a little bit larger in diameter so it doesn't go down and push into the thread so this really isn't going to work the other method also involves tapping threads and using a bolt with teflon on it and you fill the shaft with water crank down and the hydraulic pressure pumps the rotor off but not in this case this bushing has a seam going around it so any attempt to build up pressure it's just going to leak out so there still are a couple options i think first is just hitting it with a dead blow hammer so i'm going to give that a try the frame's kind of in the way so it may not work too well and lastly i could take an extra bolt i have cut it down and put a notch for a screwdriver and literally you could just screw this in until it's about maybe a third of an inch down and then do the bolt trick and just push it off so that would definitely work but it'll take less time if hitting it with the hammer works so we'll try that first yeah i think i'll just cut an extra bolt down it it is possible to get it off with a hammer but you know with the frame in the way i just can't get a good swing and once you unbolt the engine you really need two people one to hold the engine and the other to hit it so yeah let's get that bolt cut okay so i made a mark right there where the bolt exits from the rotor so i want to cut it probably right about there you know i'd actually in this case rather make it a bit too short because i can always back this screw out a turn or two if i make it too short [Music] perfect so to get the rotor off i do need to put threads on here usually i use an m12 1.75 in this case the diameter is smaller so i have an m10 1.5 that should do it so so okay [Music] aah so [Music] [Music] you all right well the valves look pretty good it doesn't look like they made contact with the piston when the connecting rod broke and the cylinder itself surprisingly i mean i know it's a little hard to see but it's actually in very good shape if i get up close here you can see the crosshatch pattern and that's shocking you know this engine is about 22 years old and obviously suffered some sort of traumatic event but from what i can see of the cylinder it looks very promising so let's get this cover off the block and see what it looks like on the inside so [Music] so oh she's a fighter okay you so so yeah cylinder is looking pretty good so i think potentially this block could be rebuilt still need to measure it up the piston itself for a second i thought survived but if you look here it is cracked and you look underneath where this pin is it is cracked on both sides so the piston is done the crankshaft a lot of aluminum transfer potentially that could be cleaned up you know the case the oil sensor the camshaft all look pretty good so i'm going to take a minute i want to get this cleaned up we'll probably quickly hone the cylinder and then we'll measure the cylinder and the crankshaft and see where we're at so just about ready to get that aluminum off the crankshaft but i did want to take a second and just highlight some pretty big differences in quality what i have up here are two sump covers they're both from the same series briggs engine the one on the right is the one we just took off that one was built in 1999. the one here on the left was built in 2009 so there's a 10 year difference between these two but theoretically these parts are mostly compatible this is the same series engine and just looking at it you can tell some pretty big differences obviously the first being the lack of an oil sensor that is critical for something like a generator that could run weeks on end the second thing is the camshaft itself you can see on the newer one it's a lot less substantial you know these holes are cut out here there's also plastic right here as part of the compression release and even the lobes are separate pieces that are pressed on to the shaft and the gear itself is pretty thin when compared to this one the older engine much beefier wider gear no cutouts and these lobes seem to be part of the shaft they're not a separate piece that was attached and of course no plastic on the compression release so much better part on the older machine and even the casting when you look at it the quality looks a lot better and this one is built a lot stronger too if you look here you have these three supports going across to add strength and on the newer engine those supports are not there at all anyway a common question people ask is can you add an oil sensor to the newer style generator and my answer is yes but why would you it's a lot of money obviously you got to take the engine apart and you know the parts actually may not be available i did take a look for the price on that oil sensor and it's discontinued i mean it's not to say that there isn't another one that could fit in there but it's not readily available from this parts diagram so even if it was available it's probably 45 50 the casting here will accommodate it but you do have to tap these threads also the wire exits through here which isn't machined out so you have to machine that buy whatever you need here to cap this off and keep it from leaking and that's not the end of it you also need the low oil module which is a critical piece to the low oil system this part actually is available it's 45 dollars and that also means you have to upgrade your switch if you have an oil sensor you need to have three tabs going into this switch the third one for the oil sensor itself and these switches aren't cheap either i don't know exactly how much this one is but i think they're around thirty dollars so all in you're looking at a hundred dollars in parts if you can find that part and it's a lot of labor to do it so you know i say just check your oil and you'll be fine so to melt the aluminum off i am going to use muriatic acid it works quite well for taking off aluminum it is pretty strong and can attack the iron here and actually cause rust and pitting so don't go crazy with it don't keep it on too long and most important make sure you neutralize the acid with baking soda and water when you're done all right we're at the 10-minute mark gonna take a look and see how we're making out yeah got a ways to go but it's starting to clean up anyway this usually takes about 30 to 40 minutes total so i just continue on like i am and turn you on probably the 40 minute mark and at that point we should be ready to polish that journal so it's about 40 minutes now just gonna take a look it is actually coming off slower than normal there was quite a bit of build up of aluminum so i have a feeling i'm going to have to go a bit longer yeah this side looks pretty good i don't see any defects in the journal now there is still some chunks of aluminum stuck on the bottom here and still quite a bit right there so it's going to need at least 10 more minutes well it came out pretty good actually haven't even touched it with sandpaper yet there is a little teeny spot of aluminum still on the bottom so i think i'm going to hit that for a few seconds with some 800 grit see if it comes off and yeah i'll probably stop at that point i do want to sand it with 1500 and thousand but let's measure it up and see if it's even worth it you yeah that did it about 20 seconds and there's no more aluminum on this crank so that's a good sign i give this one hope i am going to hit it with 1500 and 3000 grit while i'm here and then we'll measure things up yeah not too bad you'd never know what this thing had been through so let's see if there's enough meat left on this journal all right now the moment of truth the reject size on this is 1.2475 or 1.2465 it depends on which document you look at there is some disagreement on what this should be the service manual is the higher number 1.2475 but that manual i have found some other errors in it that were 100 wrong so my confidence in that manual isn't too high the 1.2465 comes from a briggs i think common specs chart which is widely published on the internet so i tend to believe that one a little bit more hopefully the specs are above both of those conflicting reject sizes but if not we'll have to make a decision okay okay so the results are in and it's it's not clear i guess the path to take on this one looking at these numbers i took three sets of numbers in each direction top to bottom left to right starting on the pto side we are within spec 1.2475 but then we get 1.2473 1.2474 so these two are slightly out of spec all these numbers are within spec now this kind of is not clear cut as far as how to handle this you know this service manual clearly says 1.2475 but i have found other mistakes in this manual so i'm not really giving this one too much credit uh this other document the briggs check chart it is published by briggs and stratton it lists it as 1.2465 and i know you probably can't read this so i'll put this up on the screen so yeah i guess the point is it's within spec according to one of the briggs documents and it's very close to inspect according to the other briggs documents so i'll probably use this crankshaft but let's measure up the bore and see if that even matters okay the board gauge has been calibrated i set it to 3.12 inches and i may have done that a mistake i noticed after the fact there is a range the nominal amount is actually 3.119 but this is set at 3.12 anyway what i'm looking to see here is that the wear is less than 4 000 of an inch so each increment on this dial is equivalent to half a thousandth so i can only go up to about eight lines and then it's out of spec also it needs to be round and there's a spec on that it's one and a half thousandths out of round should be rejected so i'm just checking the top of the ring travel first and that's maybe half a thousandth of where that's good same there and now the bottom yeah that's good let's check the other direction we're right at zero about half a thousandth there and about a thousandth aware so that's good actually uh we're within spec we don't have too much where we're not out around so it's looking pretty good i'm going to take a minute just measure up these bearings here for the crankshaft as well as the camshaft and i'll measure up the lobes and just everything else make sure we don't have any other issues but things are looking pretty good i'm happy to report everything that i measured is within spec and not only in spec it's close to the standard spec which means there's minimal wear on the bearings for the crankshaft or camshaft the lobes as well as the journals on the camshaft come in perfect as well as these journals here the pto side and the flywheel side journals everything's pretty much right at standard specs so there's no question about it everything else is good this here is the only gray area you know i wish i knew which spec was right apparently briggs doesn't know either because these two documents don't agree so we are well within spec of the lore of the two numbers and pretty close on the higher of the two numbers so i feel pretty comfortable ordering a new connecting rod and piston so that's what i'm gonna do that'll take me well that'll take at least a week before they get here so while i'm waiting on that we do need to do some prep cylinder needs to be honed valves lapped and i'll probably paint up the exhaust while it's off definitely putting the cart before the horse but i've got a week so why not okay the parts are on their way so i want to finish prepping this we'll start just with cleaning the head surface and for that i usually use this plastic 3m roloc disc it's 120 grit and it's meant for cleaning head gasket material off of aluminum some other tools i use a little bit of scotch brite wd-40 and only when i need to this razor blade i try to avoid using it because it will scratch the aluminum if you're not careful you can even see here this head gasket must have been blown right there because there is definite exhaust exiting from the side of the head so this engine would have been down on power when it was running yeah something like that so i'm going to do the same to this surface as well as the other side of the head and the sump cover okay all the surfaces have been cleaned all the gasket material is off here on the on the case as well as the cover also did the mating surface here on the head still need to do the valves and obviously you just saw me hole in the cylinder so it is ready to accept a new piston and rings and i was just turning my attention to the oil sensor i wanted to test that and notice something which leads me to believe that there's no way this sensor could have worked you know looking at it closely i saw the insulation kind of kind of looked like it had peeled away there so i grabbed the wire just to see if it was connected and this is what i saw that screw is loose so there's pretty much no way that sensor would have been able to kill the engine and i think even worse if that screw had come loose it would have chewed up the engine pretty bad so thankfully that didn't happen i am going to remove that screw put some loctite on it tighten it back up and then we'll run some tests to see if that sensor even works okay well i think you missed it but you didn't miss much i just pulled the screw out put a bit of loctite on it and reinstalled the screws so the wire is tight now and i did the same to that side so let's uh hook up the multimeter and see if this thing even works okay so i've got the multimeter set to ohms put one lead up here which is the wire that exits and goes to the ignition coil to kill spark and the other wire can go anywhere on the case so right now we should have a connection and we do because there's no oil in here so the float should be down and we should be making contact so the sensor seems to be working now if i rotate this upside down the float should move away from the reed switch opening this connection up yep and it did so we got no connection let's turn it back and there we go seems to be working i mean the connection actually isn't as good as it was a second ago but i don't have the values as far as what's good and what's bad you know that is a connection it will send something to the oil module and hopefully that's enough for that module to kick in and shut the engine down but yeah the switch seems to be good but the wire was loose okay i'll let that sit for an hour or so it'll help clean things up and also highlight any leaky valves i'm a little bit impatient it's been half an hour and at first i thought it was leaking given what's going on down here but actually that was just sneaking out through the spark plug hole when i look at the valve stems themselves they're dry this here is the exhaust turn it around and that's the intake so the valves are actually doing what they should you know lap them anyway but for now let's get this cleaned up the plastic brush that i have doesn't fit in here so what i do instead is i use a little dremel wire brush i have a brass one and a stainless steel one and the brass one theoretically is better but i find it drops a lot of bristles and it takes a lot longer to clean so i'm going to use the stainless steel one regardless of which one you use you don't want to hit any of this surface any of the sealing surface and when you're done make sure you wash it out blow it out and really inspect that to make sure there's no bristles left in there uh anyway you get the idea this is going to take a little while to get it perfect you know and honestly you don't have to get it perfect you really just want to knock off any chunks that might break loose during combustion and you know at this point it is runnable but of course when you do this it does get a lot of carbon kind of in between the valve and the seat so even if your valves did seat well before you know now it's probably not unless you open the valve up and clean out that area but i'm going to lap them anyway so not a concern so to get these valve springs off you don't have to remove the rockers but it'll make it a lot easier if you get these out of the way in order to get the valves out you need to compress the springs there are these keepers that are holding the springs in place you get the keepers out then the spring and the valve should come right out you yeah before lapping these i'm just going to clean these valves up a bit there's a lot of carbon on here anyway the the best way i've found is just to put this in a drill put a little wd-40 on it and hold a piece of scotch brite here and just let it polish up real nice it'll knock a lot of this carbon off and then we'll lock the valves yeah i got a ways to go but you get the idea i'm just going to do that for a bit until it cleans up and do the same on the other valve there's a close-up look at the intake cleaned up very well the exhaust would need a bit more work to make it perfect but it is a million times better than what it was so i think we're ready to get these lapped in and we'll put the head back together okay we'll start with the exhaust valve you don't need a lot of this grinding compound you want to be careful not to get it on the stem really just want it on the lip of this valve make sure you get all the lapping compound off both the valve and the seat i'm also going to wash this out after just to make sure but what you want is a nice line going around the valve kind of like that anyway i'm gonna do the same thing to the intake then we'll put this back together the intake also looks good get a nice line going all the way around so i'm going to take a minute just spray everything out with some carb spray still need to wipe up the lapping compound off the seats and then we can put this thing back together okay let's get this thing back together i did keep everything separated the exhaust valve is on the right and the intake on the left i don't know if these springs are different they don't look different but better to be safe and these are tapered so put the narrow end down you so this is about as far as i can take it everything's prepped and ready to go we just need the parts and the first part did arrive today we've got the piston and the rest should be here pretty soon but this video we've already covered quite a bit we're approaching the hour mark and we still have a ways to go we have to reassemble the engine test the engine reassemble the generator and test the generator so i think this is a good place to cut we'll pick up where we left off next week and hopefully finish all that up so i hope this video helps someone thanks for watching

Channel: James Condon

Views: 145,281

Keywords: 205412, 205412-0130-E1, Blown Engine, Blown Head Gasket, Bore Gauge, Briggs and Stratton, Clean Journal, Crankshaft Journal, Dial Gauge, Engine Rebuild, Fixed, Free, Generator, Hone Cylinder, Lap Valves, Muriatic Acid, Oil Sensor, PM0545005, Powermate, Remove Generator Rotor, Remove Generator Stator, Small Engine, Teardown, Test Oil Sensor, Troubleshooting

Id: BIUUrxTaRjk

Length: 55min 42sec (3342 seconds)

Published: Thu Apr 29 2021