D3 Dozer Hydraulic Repairs. Re-pack. Re-rod. CAT D3 Bulldozer.

hey there welcome back to Farm Craft lots of you know I lost my mind and bought a dozer recently done a lot of work on it so far but today we're going to address the Hydraulics several things that I need to fix here let me show you this cylinder right here this is one of the lift cylinders lifts the blade up it's the worst one because it needs a new Rod the Chrome is gone it's leaking like crazy look how much oil there is on that rod there's a constant puddle of oil underneath it so that Rod needs to replace the cylinder needs to repacked the hydraulic oil filter is there I need to take that off change that and we'll drain the hydraulic oil and refill that and then the lift cylinder on the other side it looks like the rod might be okay but the seals have gone and it's leaking as well we fixed this fitting in video number one and it's doing fine not leaking anymore and the rest of the cylinders on here are good yeah we got two cylinders to pack one rod to replace hydraulic oil to change let's get to it not a very impressive drain for the hydraulic tank it's just a petcock that looks like it's lost the handle just like the other side did and it's supposed to dribble out through this little hose I guess that's a metal hose I'll see if I can get that to open a pair of vice grips I guess the other end of that hose is right here so I can take it down into this and then down into my drain pan [Music] yeah that thing's just barely dripping so used to blowing out hoses when uh when they're plugged it's like yeah just uh just take an air gun and blow in that thing well what I'm going to be doing then is blowing whatever junk is in that hose right into my hydraulic system we do not want to do that so I think what I might do is see if I can take the cap off and just blow a little air in there just to help try to blow it this way blow it out clean trash bag and a blow gun here foreign still going to take a while well fortunately I don't have to have it drained to start working on the Hydraulics changing the oil is just something that I wanted to do because it's a new Dozer I don't know how long that oil has been in there don't be fooled when oil looks good the oil in my lift looked really good when I got it and it's not something I ever caught on video so I didn't show it in a video but I was getting intermittent cavitation at times when I was using it which is really bad for hydraulic pumps I was trying to figure out what was going on and when I changed the oil it never did it again so the oil looked good you know it was nice and Slick it didn't have water in it everything looked fine but that oil was old and it was not doing its job anymore so if you got to know how old the oil is and here's our first victim you know one thing that really surprises me about this machine is the lack of grease fittings [Music] foreign so on the back side of this thing there is a a set screw I certainly can't see it but there it is hopefully after I get that out of there getting this gland off won't be that big of a deal you may recall the last time I was fighting to get a gland off it was a cylinder that was probably worth more than this bulldozer Reef I bought an Amazon special so hopefully this is going to make this one a little easier I'll go this way I thought I broke it at first I guess I just didn't have it latched well enough man foreign need some eye protection on I feel like that Chain's gonna explode right in my face this will do it wow all right we're gonna have to do some heat thank you [Music] grief I need to be hotter than that [Applause] oh come on can't believe that won't move I mean to this wrench's credit I'm three feet out and I'm putting my whole body weight on it 600 foot pounds won't move it nothing like the smell of sizzling seals all right look at that why that one was so stubborn now this Rod I think I'm going to be keeping so I don't want that gland nut just uh scraping on it like that [Music] sure was easier than the other side oh there it comes foreign there's the O-ring that seals it oh crap forgot about this that's nice oil all over my welding blanket what a treat what could go wrong there an oily welding blanket I can't think of a thing if I try to pull that out like it is I'm going to be fighting negative pressure basically making a vacuum so I'm going to crack this line to let some air go in there oh wow so I'm going to try to use compressed air but I don't want to launch this thing error you know is a Big Spring it can build up some pressure and do some unexpected things sometimes so [Music] foreign looks good huh backup ring disintegrating now there's not much this thing doesn't take off but that's one of them foreign that really stinks why do it that way not just put a nut there because now I have to thread that I do not have a tap for that looks like we're going to be doing some single point threading all right let's see if I got the right seal kit definitely not that's a bummer well that means a trip to the hydraulic shop boy that came out awful easy so those are the gland seals now the piston this is kind of interesting this wear band wear bands oftentimes you can just pull off very easily and the purpose of this is to the cylinders laying on its side and the seal itself which is this is not good at taking that lateral Force so this takes the lateral Force and takes the pressure off of this this will compress a little bit into it but it won't sit there and get smashed and what's unusual I've never seen this before this guy is split you just separate it interesting and then it looks like there's an O-ring underneath this gives it some preload it pushes the seal against the barrel wall yeah and it was on the gland here where there was a backup ring that disintegrated so I need to take that other cylinder off and get the backup ring off of that to bring to the hydraulic shop there we go and now a screwdriver yeah there's the backup ring that I'm after hmm I can tell you that gland moves on that Rod way too easy [Music] I think so wow too much air leaking for the air pressure to push it out but I can't pull it out by hand so I'm gonna have to come along that or something all right here's the setup got the old pickup truck and the come along and we're gonna pull that thing out of there [Music] [Music] why is the thing so hard to come out I mean there must be something in the barrel there that's hanging on those seals because the Piston never comes up that far right I'm going to replace this stretchy rope with a piece of chain which will make it less likely to Launch [Music] grief [Music] what's going on here time to reevaluate I mean the barrel feels fine uh this port right here I don't feel any Burr sticking out but that's right where it was so I have to think that's what it was otherwise it all seems good but I'd pour it up there I think just kind of has a sharp edge and the seal going by it is digging into that edge and just holding up so I'm just going to reach up in there with a little round file and try to knock that edge off oh I think it's coming all right well I was trying not to hit that Rod but okay look at that gland that's a little too loose yeah inside of the barrel looks perfect see if this one's going to fail me again [Applause] foreign rip my Vise off of there all right here's my backup ring if you can see that side right there is concave and then the other side of it is flat o-ring goes towards the pressure concave side goes against the O-ring and the purpose of the backup ring I didn't understand this until I did a video on it recently and several people explained it is to back up the O-ring you got to think of hydraulics as directional the pressure's coming from one side and trying to get out well without the backup ring there this soft rubber could potentially get extruded right through the Gap that exists between the two pieces of metal at your ceiling so you need something behind it to help support it but you also need the squishiness of the rubber to make the seal so you combine the two properties something that's strong the backup ring and something that's squishy the O-ring foreign I got several challenges that I'm not sure how it's going to go um one these rods might be hardened and I have carbide tooling which should be able to handle it but I don't know it's probably not like top of the line carbide so we'll have to see how that goes the ones I bought are definitely hardened so same issue there I'm going to need to do some turning on them and then cutting this weld it would be nice to have they're called button inserts and I don't have any that's one thing but the big thing is this I was not expecting this to be a bolt typically this is an external thread here the piston would go on to a shoulder and then thread would be sticking out and you'd have a nut that you tighten down I've never seen one like this I don't know what the advantage is of doing it this way but it definitely makes it maybe it's easier to machine if you have the tap the threads go in quite far I mean they go into like there and that's only a one inch hole so reaching in there with a Threading tool and trying to thread that deep is going to be a bit of a challenge I cannot get that tap locally I'd have to order it I'd have to wait yeah I could but you know I've got a lathe let's see if we can make this happen I've got this boring bar which will allow me to reach in it's pretty heavy I can use it with one inch and it just takes high speed steel quarter inch square stock and so I need to make a 60 degree threading tool so I already put a little bit of layout die on that and scribed this is just a 60 degree angle gauge and I've scribed my 60 degree Mark so I'm going to take that over to the Belt Sander and we're going to get it right on 60 degrees all right so there's the angle that's good now it needs clearance underneath I'll just take it on a diamond Stone and hone it all down a little bit a little radius on the end all right 160 degree thread cutting tool all right so first thing I need to do is take this eye off it here now I need to turn this weld down I don't really have the best tool for it I'm going to start out with this and get as deep as I can and then I'm going to have to go to a parting tool and we'll see how it goes [Applause] [Music] [Applause] [Music] [Applause] thank you [Music] foreign [Music] so this is a brand new piece of induction hardened one and a half inch chrome Rod so now I need to make this into this so this has this one inch hole and a chamfer a little bit of a relief there and then the threads the dreaded threads I have a plan I'm going to thread away from the Chuck something I've never done before but should make this a lot easier makes it less likely that you're going to crash much less likely I want to crash the lathe pretty so this is my first attempt at turning this hardened steel and you can see where it's hard it throws lots of Sparks pretty hard on the carbide just shy of Two and a Half that'll work all right now I'm just taking this one inch bit to cut that outer section okay 885 and I need 9 35. I'm at 8.95. I need 35 so I got 40 thousands to go now I do want to bore this outer clearance off just a little bit more too but that's not critical of the dimension I'm just going to take a little bit off okay now we need some chamfers this is going to be my first time really trying to machine this hardened stuff so I'm actually going to take one of my this is probably going to fail but I'm going to try I have these things that are supposedly carbide but they're garbage I'm just going to sharpen this up on a diamond Stone and then see if I can get it just to give me a chamfer there oh tried to cut it for a second garbage I'm just gonna throw those things away all right I've got a carbide insert the tip broke off of this and I didn't throw the insert away just in case for something like this this Edge right here should still be good so let's see if this carbides up to the task these are better quality that'll do I've pushed up a tiny little bit of a burr on the face there I'm going to take that off now we're ready to thread this sucker this is the fun part so I'm just squaring up to the work using the face of the chuck to make sure I'm Square all right so there's our threading tool I've got the lathe set up to do 14 threads per inch which is what I need so what I'm doing here typically you thread towards you and you feed towards the Chuck so I'm reversing both things which means the lathe's going to be spinning the opposite direction and I'm going to be feeding away from the Chuck so it still makes a right hand thread there's nothing different except there's nothing to crash into which is a big difference that's really nice because you can't see much it's a small hole you know when you're coming towards it and this is going to hit if you don't stop in time it makes it a lot harder right now The Cutting Edge is aligned with the face that's good so I now have a zero set and that is where I'm going to start my thread and I mean I'll do my best to explain this internal threading is impossible to video I can't see anything when I'm doing it let alone filming it but basically I'm going to be making little tiny passes and coming out and cutting a thread if you want to see more on threading I've got a video I'll put a link to it here where I threaded a real long bolt and kind of explained how the whole threading process works so check that out if you want to learn more so what I'm going to do first I'm going to touch off and then I'm going to look at my depth and I'm going to plunge in what should be I probably need to go like 80 thousands to make a place for me to work out of then I'll come back to my zero and that's just going to make a Groove the deepest portion of the thread will just have a Groove going all the way around because I'm not doing any feed while I do this I'm just plunging [Applause] there's my zero that's 20 30 40. why not 100. okay back to zero first one you can do a pretty heavy cut I'm gonna go in 20. off camera I already confirmed that this thread is correct so now I take the cross slide back to zero that disengages me from that cut I can advance all the way back in to my zero here so now I'm at that Groove that I cut now I can bring this back to zero so now I'm exactly where I was when I just did my last cut let's Advance this I'll just do five thank you [Applause] so cross slide out so I've disengaged from the threads I come in and I'm going to go to this zero so I get the carriage now I'm on that Groove I can bring this back to zero so I'm right where I was when I did my last cut and then I Advance the compound that way we'll do ten thousands [Applause] that was a little bit of a heavy cut I'll do fives from now on I think [Applause] zero [Applause] zero zero [Applause] all right here's one of the bolts wow that's close yeah it's definitely going to need probably more than a spring pass but not much more I'd rather not overshoot so I'm just going to do a spring pass and what that means is there's spring on the the bar sticking out it bends down as it's cutting and if you do the exact same measurements again you're going to get another cut just because now there's less pressure on the tool that won't Bend as much so it'll be in the work a little bit more so we're going to cut that exact same thing again second zero and then back to zero here so right there is where I did my last cut and we're just we're not going to change anything I'm not going to dial this we're going to go again see I actually got a lot of chips out of there not more than I was expecting foreign all right it's a little tight up in there I'm not sure there must be a burr or something on the thread I'm gonna do another little pass I bet you that's exactly what it needed oh yeah much better okay threads are done awesome yeah I could have bought a tap one that would have done it was like 40 bucks and uh I probably never use it again so and then I would have had to wait that was really the main thing so I saved 40 bucks and I didn't have to wait awesome I think that's gonna work all right obviously the new Rod is longer and I've done careful measuring about five times to make sure I don't mess up I need my rod to be 19 and 1 8 inches long so I'm gonna need to get through that hardened layer now I know a ceramic insert is the way to go I don't have ceramic inserts I was not able to find any for a reasonable price I found a place where I could order a box of them and it was going to be a hundred dollars so I'm gonna see what I can do to get through it without I may have to resort to abrasives so I need it to be 19 and an eighth and then I'm going to drill it 5 8 so that that will fit in there and then I need to kind of bevel it back so that I have room to get my welder down in there and make a new weld what I have here is an old insert that I touched up on a diamond Stone to see if I could just get a little bit of cutting out of it through this hard stuff don't know if it'll work [Applause] [Applause] as we're doing surprisingly well [Applause] [Applause] it did to the tip of that that thing was a nice point and it is just gone now so I've got another one that has a point on it that's starting to wear out [Applause] [Applause] [Applause] oh [Applause] you know one thing I could do is come over here with an angle grinder and just grind it off but then I'm throwing abrasive all over my lathe I don't really want to do that all right I think I finally got it that was a fight there we go [Music] thank you that's the induction hardened layer and the rest of this is not hardened so it's much softer [Music] [Applause] [Music] now I need to set this thing up so that I can do some welding without destroying my lathe all right I got my welding blanket every inch of my lathe waves are covered and I am I just got the paint off of that so that's where I'm going to put the ground clamp I'm going to cover the eye up the only thing that's going to be exposed is what I'm welding I got a piece of copper here foreign [Applause] well it's not cutting edge engineering but uh it's actually working pretty well [Applause] foreign a little ugly grinder and paint makes me the welder I ain't all right got my new seals as usual there's been slight modifications to things so this is the actual seal the oil pressure seal and that's the same it's just a different color this two-piece thing that I had not seen before that is a buffer basically when there's a pressure spike this will take some of the strain or pressure off of the actual seal it acts as a buffer the old one was a two-piece buffer this one's a one piece so there's that there's the wiper this is the O-ring and backup ring and the Piston seal the old one had the the split seal and then an O-ring around O-ring for preload this one does not have a split seal and has a square one for preload and this one is pretty stiff I may have to heat that one up but we'll see how this goes the wear bands they didn't have these wear bands but the good news is and you can still see the part number on my wear bands they're they're basically like new all they have to do is hold up against sideways pressure it's not like it has to not leak so I'm fine with reusing the old wear band so we'll be doing that so the buffer goes in first Maybe hey okay now next is the actual seal and I have a new tool for that see how that averts it put it down in there foreign pop it in all right let's see if we can coax this wiper in here okay these guys have a flat side usually in a concave side the concave side goes towards the pressure yep okay that's a rebuilt gland yeah how's the Piston gonna go foreign we're going to be heating that up a little hydraulic oil amazing what a difference that makes um here I'm going to go ahead and do the other piston one wear band right back on there second wear band let's knock out the second gland I took these old seals in cat did not have their seal kits in stock and they were 126 dollars a piece I took these into the local hydraulic shop that just does all sorts of stuff they're also the Yanmar dealer and they gave me both sets for 120. actually it was a little less than that still seems like a lot for some pieces of plastic and some O-rings but what are you gonna do all the seals are in foreign so this rod cost me 65 dollars other than that it's the seals so 120 bucks basically for all new seals and a new rod on a cylinder man if I hired someone to do that we're ready to start putting this thing back together and that is a serious wiper there it is so torque wrench really isn't an option for me with this one I don't have a wrench that would go this high foreign the second cylinder went much the same [Music] so I'm past this port now I should be able to uh use the Hydraulics to do the rest all right now this is going to tear up my nice new paint job but oh well nothing you can do about that click um foreign I think I'm gonna go ahead and get this eye in place okay now the hydraulic oil filter housing is right there so I'm going to need to take that out looks like there's a drain plug so I guess I'll drain as much out as I can so that when I take it out of there I don't make too much of a mess this sight glass is really fogged up and that's how you're supposed to check the hydraulic oil it would be nice if that worked looks to me like I'm going to have to take that off to clean it [Music] [Music] foreign [Music] [Music] there I guess you can see the problem that thing is totally to clean that up here just to show you you can actually see through that thing now [Music] [Music] okay foreign [Music] nice and clean in there so there's an O-ring up there but it looks to be in good shape it was not leaking I'm going to leave it alone some people might wonder about why I didn't pre-fill that well that's on the return and most hydraulic systems your main filter is on the return You Can't Get Enough suction to get enough oil through because you can only get atmospheric pressure worth of pull when you're on the suction side on the downstream side of the pump you have as much pressure as you need to push it through that filter so you get a lot more flow with a smaller micron filter there are suction filters on hydraulic systems my excavator has one but it's like a probably a 50 Micron it's really there just to keep particles of rust from the tank getting sucked up by the pump this is the main filter and this is Downstream of the pump so this not being full of oil won't hurt a Thing Once the pump starts running it will fill this up and then dump it into the tank so this is 10 weight drivetrain oil is what they called for and I could only get this from cat so all right yeah now that's going to drop when I run it because I got to fill those cylinders I got to fill the filter and we'll add more [Applause] just letting it idle for a little bit to circulate the oil the filter would be full now and you can see how much it's dropped [Applause] [Music] [Applause] [Music] [Applause] [Music] [Applause] foreign [Applause] [Applause] you know I get a lot of questions about bleeding hydraulic systems so a brake system is very different from this a brake system is kind of a one-way hydraulic system you've got a line that goes to your caliper pushes on the brake pads and if there's any air in there you're going to get a Big Spring and it's not going to be able to push very hard this is very different because you're getting a big amount of flow of oil there's a little bit of oil in the lines but the vast majority of the oil every time you cycle this thing is in the barrel so that Barrel then gets mixed with the air and then when you cycle it the other way it all goes back to the tank and the air just Rises to the top of the tank and comes out of the system there's a breather on the hydraulic tank so all you have to do is cycle a cylinder back and forth and all the air will come out I've had hydraulic mechanics tell me it helps to deadhead at the very end of the stroke in other words take it as far as it'll go and then hold it there and let the relief valve take some of the flow at that point but either way you really don't need to worry about bleeding these kind of systems so much they'll self-bleed foreign so what have we done on this machine we changed the fuel filter we checked for a screen behind the primer pump which does not seem to be there and I can't find we changed the engine oil and filter we replaced the seal in the governor and we fixed a hack job of an alternator we welded on the exhaust put a new pipe and we fixed up the the top of the stack there which still needs a little bit of adjustment because you can see it's hanging open we cleaned the air pre-cleaner we repacked this cylinder and put a new rod on it we drain the transmission oil and cleaned out that screen underneath there we did some wiring in the console here to fix the hour meter got the oil pressure switch working made sure the breaker worked we change the hydraulic oil and the hydraulic oil filter we cleaned out the sight glass so that we can see that we change the bevel gear oil we changed both final drive oils and we patched a leaky final drive under there and then also put a protection on that one we drained the fuel tank and fixed the petcock valve for draining it next time we made this board so the battery would stay in place we also put some protection on the wires some wire loom we tightened up our throttle so that it'll stay in place and off camera I also adjusted this so that it won't go into gear accidentally we had to make a custom wrench to tighten the fitting under there we repacked this cylinder we cleaned out that radiator power washed the whole thing changed the air filters patch the crank case breather and put a new breather in it and again a little wiring here fixed one of the loose track plates and I'm probably forgetting something but that's all I can think of right now well there you go guys all the Hydraulics are fixed and you know I really wish I could say we're ready for action ready to put this thing back in service because like I said I have a job coming up with it and a lot of you guessed it too I'm really looking forward to getting out there and pushing some dirt around with this thing but many of you have made really good comments on additional things that I should do to it and one comment in particular something that I had not considered whatsoever and not doing it very well could have led to the early demise well I don't know if you can call it an early demise but not doing it could have led to the demise of this machine and uh man I hadn't even thought about it one bit but I'm going to take care of that before we put it back in service plus several other things so we're going to have one more video of repair on this Dozer before we're ready to roll so look out for that one coming soon and thanks for watching we'll see you guys on the next one thank you wow [Music] [Music] [Music] thank you [Music]

Channel: FarmCraft101

Views: 98,477

Keywords: heavy equipment, dozer, bulldozer, hydraulic repair, hydraulic cylinder repair, repacking, repacking hydraulic cylinder, hydraulic cylinder rebuild, cat equipment, D3 dozer, D4 dozer, cat dozer, cat d3, CAT D3

Id: hvA10pHZwQw

Length: 62min 4sec (3724 seconds)

Published: Fri Jun 16 2023