Nicely done video, with tons great points! I have 1985 cat d3b dry setup they are very simlar in designs. I recently pulled my steering clutches and brakes and installed all metal disc with the bronze faced linings (they are made to run dry,) major upgrade for the d3's! Thanks Nate
Hello Jeremy, I have to say this is by far the best video on UA-cam showing how to replace the seals and bearings on Komatsu D20’s and D21’s. I have looked for almost for 6 months now on how to replace seals and bearings on these Mini dozers. Impossible, can’t even get anything legible from the pdf manuals. And parts numbers? Forget about it.. Great Job on the rebuild, Thanks for the walkthrough!
Thanks for posting this video. I'm helping my uncle fix a D21E-6 that isn't able to turn left and this video will help us a lot with doing so. Thank you and have a good day.
@@jeremydiy Does the service manual you have cover the D21E-6 as well? If yes, where can I get it? Also is there a specific website that you were finding parts on? Thanks for your time.
@@nick_is_steve No it doesn’t. I have had the best luck doing a Google search for parts. I you get a part number then put that in. I use images a lot because then you can see if the part resembles what you are looking for.
Killer video, hoping my new d20p-6 is similar as I'm about to tear into it. Pretty strange I pull either lever and both tracks just stop. Anyway, Thanks for your great contribution to us backyard mechanics.
Looking like that large bearing completely grenaded on me! Chunks of metal when the drive oil was drained! Where can that bearing be purchased?? I’ve found ONE, for nearly $350!!
Not sure which bearing you’re talking about but I think I looked them up by part number and found them on eBay. If it’s the bearing from the clutch to the sprocket, ya those are expensive.
Thank you for the reply. The bearing seems to be on back order. If possible, I have a couple of questions: the access plug to get to the brake clutch bolts is frozen, it’s now stripped out! Is it worth drilling it out, or should I just use a swivel head 17mm wrench to remove those bolts? Also, once those bolts are removed, does the clutch disc assembly just lift out?? I can feel that the bearing that the clutch assembly connects to is sloppy and likely destroyed. Any other info on this project would be appreciated! All of my steering is perfect, just had that bearing grenade on me and it would stop that side and sound horrible!
@stephenlarue6842 I think it’s worth getting that plug out. Without that access it’s going to be really hard putting it all back in. You can do a couple things, drill the centers out and use an easy out tool (the biggest one you can) to try and brake it free or weld a bolt head to it so you can put a socket on it. Which ever route you go I would soak it in penetrating oil and heat it up just before trying to brake it free. After you get those bolts off the plates on both sides, the clutch is free. I used a bar and a rope to support the weight of the clutch while I was taking it apart. It’s heavy, probably about 50 pounds.
No. The only seals I changed was the ones I showed in the video. You should be able to find a number on the old seal. Every seal I’ve ever pulled out has a part number on it. You can then search that number on the internet or ask a auto parts place. I have a bearing and seal company near me. One time the number was unreadable and they were able to measure the dimensions and find me a replacement.
I think I was able to get the seal from an auto parts store or McGuire bearing company. The bearing is a genuine Komatsu part and I just did a Google search for the part number and found it online somewhere. It’s not a cheap bearing if I remember correctly, it was like $300.
I just put clutches in mine also, but I am having a hard time putting the break linkage and the cover back together. Do you have any advice? Thanks for the video I watched it several times.
Oh ya, that was super hard. I can’t really remember. I do remember having almost everything assembled and putting the cover over the brakes and then having to insert a pin I believe patience and time is what it took.
Good job, especially for someone learning as they go. I have a 1994 d37e-5 in need of this now. TEC (kamotsu) says 120 hrs labor, 26k and some change. Parts 26k and some change. Total 53k and some change. 😮😂😢
Hi I changed my clutches and the bearing went out in that yolk a little later down road I bought new yoke and bearing now the clutch won’t release my cylinder is operating and has accurate pressure thru control. I tried adjusting the bolt on top of arm both way do you have any ideas? Tired it’s of taking it apart to adjust and readjust thanks you have done a really good job!
Are you calling the yoke the leaver that the cylinder pushes against to disengage the clutch? I talked about it at 11:47 in my video. I just want to make sure we are talking about the same thing. I would think that it has to do with the new yoke and bearing you put in. If the machine was working fine after you installed the new clutches and before you put in the new yoke but not after, then maybe make sure the yoke is installed correctly. Do you have a parts diagram? Maybe you assembled the yoke backwards and the cylinder can’t push out far enough. The yokes have a specific direction.
Thank you I’m going to tear it down again tomorrow and inspect but I’m really sure it’s in there correctly. When I get it figured out it will b too soon! I’ve replaced the whole undercarriage lots of time and money. Thank you sir
no, I mean how many hours are on the machine? I'm judging from your track wear that this was used quite a bit before the steering got to this point? Also, just fyi, Im off grid where I may be overhauling mine so, because your video was so well done, I was able to snip pictures from the vid, save to flashdrive before transferring to my phone......now I have some great stills to help me through the process! well done! @@jeremydiy
Oh, 2500. The tracks seem pretty low quality so they may look like they have more hours on the machine than it does. Glad the hear that this should help.
Hey buddy I got a D31 with similar issues and it’s pretty much exactly like yours. Do you got a email so I can ask you some questions. Let me know thanks buddy
I’m more than happy to answer your questions but I don’t want to put my email out there for everyone. You can ask your questions through this comment section or give me your email and I’ll respond. Thanks.
@@jeremydiy hey well I got almost the exact dozer , mine is the D31 ! Here’s my issue. Well it drives forward and reverse just fine , plenty of pushing power. When I first bought it a few years ago it did turn , but never turned the best. Well a few months ago it stopped turning good and I decided to tear it apart. 1- I took both sides of steering clutches out of it and replaced ( the old ones looked fine ) I replaced anyway. The springs were fine also ! 2 - my system is wet clutched also ! 30 weight oil 3- I took apart the 2 Slave cylinders and they looked great so did the o-rings . ( you said you had a company make you new ones ) 4 I put it all back together and double checked everything and replaced all the new oil in mine clutches Well it’s doing the exact same thing drives forward and reverse just fine ! I DID RELIGHN BOTH BRAKE BANDS WITH NEW FIBER AND RIVETS . I almost forgot about that Any ideas of what it could be , I thought maybe I got all those linkage arms out of adjustment . Or maybe it’s the power steering pump that sits in the middle between the clutch housing covers .
It sounds like everything is in good working order. I would double check all of your linkage that you put back together to make sure they are within the correct specs. You said your slave cylinders looked good, but you replaced the O-rings in them anyway. I’m assuming those cylinders are what causes your clutches to disengage. I think I would start looking at the hydraulic pressure that feeds those slave cylinders and any mechanisms upstream. If your system is at all like mine, there should be some kind of hydraulic control valve that allows hydraulic pressure to go to the cylinders that disengage the clutches. mine is a one-way system. Hydraulic pressure goes in and then the force of the springs from the clutches pushes the fluid back out. That fluid never gets re-circulated and sits in there for years and years. The fact that both sides are doing the same thing makes me think you need to follow the system back to a location where it Y’s off. In a nutshell your machine sends hydraulic pressure, usually via two hoses, one supply and one return, to a control valve. That valve should be hooked to your steering linkage whether they’re foot pedals or hand levers. That valve is what controls the hydraulic fluid to the slave cylinder‘s to disengage the clutches, based on what you told me, I would start investigating all of that system. It sounds like you may not be getting hydraulic pressure to those cylinders in order to disengage the clutches.
@@jeremydiy yes brother ! My machine is almost identical to yours ! Mine has steering levers , not pedals. I will get the video up tomorrow and I will message you . Im thinking it’s the hydraulic pressure like you said because when I pull the lever to steer it everything looks like it should be working, once I get the video up it will help. Im just lost with it. !! And need help badly. I purchased it to make a better graveyard for my father that passed away. I got the graveyard about half done and I have been trying to get it fixed . I was just out of ideas.. I really appreciate you !! I have done mechanic work all my life but not on heavy equipment ! So it’s a learning curve. I will Message you tomorrow. Thanks buddy
Nicely done video, with tons great points! I have 1985 cat d3b dry setup they are very simlar in designs. I recently pulled my steering clutches and brakes and installed all metal disc with the bronze faced linings (they are made to run dry,) major upgrade for the d3's! Thanks Nate
Glad you liked it.
Hello Jeremy, I have to say this is by far the best video on UA-cam showing how to replace the seals and bearings on Komatsu D20’s and D21’s. I have looked for almost for 6 months now on how to replace seals and bearings on these Mini dozers. Impossible, can’t even get anything legible from the pdf manuals. And parts numbers? Forget about it.. Great Job on the rebuild, Thanks for the walkthrough!
Glad I could give back to the UA-cam community. Thanks for the kind words.
I have an old d20p-5 was used in my small logging operation 20 yrs ago.. you inspired me to get it going.. thank you for this video..!
Glad to hear that. Good luck and thanks for watching.
very thorough. I have a D41 but I still enjoyed watching your video. good job.
Thanks
Thanks for posting this video. I'm helping my uncle fix a D21E-6 that isn't able to turn left and this video will help us a lot with doing so. Thank you and have a good day.
Thanks. Hope it helps.
@@jeremydiy Does the service manual you have cover the D21E-6 as well? If yes, where can I get it? Also is there a specific website that you were finding parts on? Thanks for your time.
@@nick_is_steve No it doesn’t. I have had the best luck doing a Google search for parts. I you get a part number then put that in. I use images a lot because then you can see if the part resembles what you are looking for.
You can purchase a shaft repair ring. They are available in both SAE and metric sizes. Work great and no more leaks or damaged seals.
Killer video, hoping my new d20p-6 is similar as I'm about to tear into it. Pretty strange I pull either lever and both tracks just stop. Anyway, Thanks for your great contribution to us backyard mechanics.
You’re welcome, good luck.
Nice work! Thats a big job. Hope it lasts a long time.
I’ve been using it quite a bit lately and it’s holding up so far.
Awesome video! My D20A5 just started locking up the right side. I guess I’ll be tearing it all down and watching your video 20x!!
Having a super tough time getting those clutch covers off. I need to take the little pins out on the inside, and they’re stuck!
Looking like that large bearing completely grenaded on me! Chunks of metal when the drive oil was drained! Where can that bearing be purchased?? I’ve found ONE, for nearly $350!!
Not sure which bearing you’re talking about but I think I looked them up by part number and found them on eBay. If it’s the bearing from the clutch to the sprocket, ya those are expensive.
Thank you for the reply. The bearing seems to be on back order. If possible, I have a couple of questions: the access plug to get to the brake clutch bolts is frozen, it’s now stripped out! Is it worth drilling it out, or should I just use a swivel head 17mm wrench to remove those bolts? Also, once those bolts are removed, does the clutch disc assembly just lift out?? I can feel that the bearing that the clutch assembly connects to is sloppy and likely destroyed. Any other info on this project would be appreciated! All of my steering is perfect, just had that bearing grenade on me and it would stop that side and sound horrible!
@stephenlarue6842 I think it’s worth getting that plug out. Without that access it’s going to be really hard putting it all back in. You can do a couple things, drill the centers out and use an easy out tool (the biggest one you can) to try and brake it free or weld a bolt head to it so you can put a socket on it. Which ever route you go I would soak it in penetrating oil and heat it up just before trying to brake it free.
After you get those bolts off the plates on both sides, the clutch is free. I used a bar and a rope to support the weight of the clutch while I was taking it apart. It’s heavy, probably about 50 pounds.
Wat's the trick to getting the covers back on attached to the brakes, Wish You video putting the covers back on
Hey Jeremy great video. Been having the same issue with mine. Do you have the part # for those inner seals?
No. The only seals I changed was the ones I showed in the video. You should be able to find a number on the old seal. Every seal I’ve ever pulled out has a part number on it. You can then search that number on the internet or ask a auto parts place. I have a bearing and seal company near me. One time the number was unreadable and they were able to measure the dimensions and find me a replacement.
Question the flange plate that holds on the yoke and throw out bearing, what size socket did you use to remove the nut that holds that flange on sir?
Unfortunately I can’t remember. I probably just grabbed sockets and tried them until I found the one that fit.
Where did you end up ordering your seal , bearing , and prong from for the final drive? Thank you Dan
I think I was able to get the seal from an auto parts store or McGuire bearing company. The bearing is a genuine Komatsu part and I just did a Google search for the part number and found it online somewhere. It’s not a cheap bearing if I remember correctly, it was like $300.
I just put clutches in mine also, but I am having a hard time putting the break linkage and the cover back together. Do you have any advice? Thanks for the video I watched it several times.
Oh ya, that was super hard. I can’t really remember. I do remember having almost everything assembled and putting the cover over the brakes and then having to insert a pin I believe patience and time is what it took.
Good job, especially for someone learning as they go. I have a 1994 d37e-5 in need of this now. TEC (kamotsu) says 120 hrs labor, 26k and some change. Parts 26k and some change. Total 53k and some change. 😮😂😢
Ouch!! Good luck. Thanks for the comment.
Hi, nice video. Not sure if your aware that the left track is on backwards. It will cause it to wear faster and not grip very well pushing forwards. 👍
Ya I noticed that as I was working on it. It came that way and I haven’t made the time to fix it yet. Thanks for the heads up.
Hi I changed my clutches and the bearing went out in that yolk a little later down road I bought new yoke and bearing now the clutch won’t release my cylinder is operating and has accurate pressure thru control. I tried adjusting the bolt on top of arm both way do you have any ideas? Tired it’s of taking it apart to adjust and readjust thanks you have done a really good job!
Are you calling the yoke the leaver that the cylinder pushes against to disengage the clutch? I talked about it at 11:47 in my video. I just want to make sure we are talking about the same thing. I would think that it has to do with the new yoke and bearing you put in. If the machine was working fine after you installed the new clutches and before you put in the new yoke but not after, then maybe make sure the yoke is installed correctly. Do you have a parts diagram? Maybe you assembled the yoke backwards and the cylinder can’t push out far enough. The yokes have a specific direction.
Thank you I’m going to tear it down again tomorrow and inspect but I’m really sure it’s in there correctly. When I get it figured out it will b too soon! I’ve replaced the whole undercarriage lots of time and money. Thank you sir
You’re welcome. It’s the only thing I can think of with out seeing it. Good luck.
why didn't you use a speedy sleeve with your new seal instead of the JB weld?
Because until now I haven’t ever heard of those. I looked them up and it seems like it would work good.
Sir d20a-5 dozer spear parts how to book in india wibsits pls tellme
Go to mykomatsu.komatsu and register. This will give you an account and you can look up the parts and book.
how many hours were on this dozer?
Not exactly sure since I only worked on it in my spare time. Maybe somewhere between 40 and 60 hours.
no, I mean how many hours are on the machine? I'm judging from your track wear that this was used quite a bit before the steering got to this point? Also, just fyi, Im off grid where I may be overhauling mine so, because your video was so well done, I was able to snip pictures from the vid, save to flashdrive before transferring to my phone......now I have some great stills to help me through the process! well done!
@@jeremydiy
Oh, 2500. The tracks seem pretty low quality so they may look like they have more hours on the machine than it does. Glad the hear that this should help.
Hey buddy I got a D31 with similar issues and it’s pretty much exactly like yours. Do you got a email so I can ask you some questions. Let me know thanks buddy
I’m more than happy to answer your questions but I don’t want to put my email out there for everyone. You can ask your questions through this comment section or give me your email and I’ll respond. Thanks.
@@jeremydiy hey well I got almost the exact dozer , mine is the D31 ! Here’s my issue. Well it drives forward and reverse just fine , plenty of pushing power. When I first bought it a few years ago it did turn , but never turned the best. Well a few months ago it stopped turning good and I decided to tear it apart.
1- I took both sides of steering clutches out of it and replaced ( the old ones looked fine ) I replaced anyway. The springs were fine also !
2 - my system is wet clutched also ! 30 weight oil
3- I took apart the 2 Slave cylinders and they looked great so did the o-rings . ( you said you had a company make you new ones )
4 I put it all back together and double checked everything and replaced all the new oil in mine clutches
Well it’s doing the exact same thing drives forward and reverse just fine ! I DID RELIGHN BOTH BRAKE BANDS WITH NEW FIBER AND RIVETS . I almost forgot about that
Any ideas of what it could be , I thought maybe I got all those linkage arms out of adjustment . Or maybe it’s the power steering pump that sits in the middle between the clutch housing covers .
@@jeremydiy I will do a video of it tomorrow and post it on my UA-cam channel here and you can look at it and maybe see if you have any ideas.
It sounds like everything is in good working order. I would double check all of your linkage that you put back together to make sure they are within the correct specs. You said your slave cylinders looked good, but you replaced the O-rings in them anyway. I’m assuming those cylinders are what causes your clutches to disengage. I think I would start looking at the hydraulic pressure that feeds those slave cylinders and any mechanisms upstream. If your system is at all like mine, there should be some kind of hydraulic control valve that allows hydraulic pressure to go to the cylinders that disengage the clutches. mine is a one-way system. Hydraulic pressure goes in and then the force of the springs from the clutches pushes the fluid back out. That fluid never gets re-circulated and sits in there for years and years. The fact that both sides are doing the same thing makes me think you need to follow the system back to a location where it Y’s off. In a nutshell your machine sends hydraulic pressure, usually via two hoses, one supply and one return, to a control valve. That valve should be hooked to your steering linkage whether they’re foot pedals or hand levers. That valve is what controls the hydraulic fluid to the slave cylinder‘s to disengage the clutches, based on what you told me, I would start investigating all of that system. It sounds like you may not be getting hydraulic pressure to those cylinders in order to disengage the clutches.
@@jeremydiy yes brother ! My machine is almost identical to yours ! Mine has steering levers , not pedals. I will get the video up tomorrow and I will message you . Im thinking it’s the hydraulic pressure like you said because when I pull the lever to steer it everything looks like it should be working, once I get the video up it will help. Im just lost with it. !! And need help badly. I purchased it to make a better graveyard for my father that passed away. I got the graveyard about half done and I have been trying to get it fixed . I was just out of ideas.. I really appreciate you !! I have done mechanic work all my life but not on heavy equipment ! So it’s a learning curve. I will Message you tomorrow. Thanks buddy
It is a D21 A, not a 20. Mid 1980s. I have the same model. Should be a serial number tag on the left side.
No it’s not. The lag on the left side says D20 A. Also, all the parts I look up in the parts manual are correct for a D20.
Sorry my mistake, I have a D21A mid 80s, looks a lot alike from the cab area.@@jeremydiy
No weld it then machine it back to specific size