Section for komatsu d20,21 and similar grey market dozers

[darinray]

1992 according to my book.

 

[K5Cruz]

I had a seal blow on one of my blade angle cylinders today, and one of my lift cylinders has a leaking seal. Where is the best place to find the seals and is this something I can do myself without any special tooling? I've never rebuilt any cylinders before, and advice?

 

[johnmoore]

Welcome aboard rangerfreak:drinkup , I'm not a Komatsu expert but there are a few guys here that do qualify. So fire away and someone will probly answer all your questions.

Can anyone please tell me what the bearing number is for a final drive on a
D20P5 is. I have called everywhere and nobody can tell me. Mine is wore off so I can't read them.:Banghead

 

[oldhousehugger]

I had a seal blow on one of my blade angle cylinders today, and one of my lift cylinders has a leaking seal. Where is the best place to find the seals and is this something I can do myself without any special tooling? I've never rebuilt any cylinders before, and advice?

Get the exact part numbers from Komatsu (Continental Equipment here in Dallas south of town on IH 45). Continental will print you out an exploded parts diagram and parts list for each component you ask about if you go in person. Don't buy it there.

Then call H&D Distributors in Dallas. (3236 Irving BLVD in the white pages).
It's better if you go in person with your old parts in hand so they can match stuff exactly. They will match up all your seals and they told me although I haven't tried yet that they have kits for all the Komatsu cylinders. Their prices are a fraction of OEM and they are very knowledgeable and they have a whole universe of O Rings, hydraulic seals ETC. Most of the jobber hydraulic cylinder and pump repair shops in town have will call bins of their own on the wall so I guess if it’s good enough for them it’s good enough for me. Their location is handy as well because there is a great bearing and seal place right across the street, which also carries hydraulic hoses etc., and rotational seals and stuff.

I was working on a 68 Ford Backhoe and rebuilt the power steering pump and power assist cylinder for pennies on the dollar compared to OEM. (New Holland).
Make sure all your parts are spotlessly clean or they will give you the evil eye. Also make sure everything is completely disassembled because when it's your turn they won't wait for you to take it apart there. They have a $10 dollar minimum purchase which can be a little frustrating if all you need is one ¼ inch o-ring but nevertheless they are a terrific resource.

I have read instructions here on this site concerning disassembling your cylinder right on the machine. One thing in particular makes sense. Use the OEM connection at each end to hold your part while you loosen the fasteners. You may be talking several hundred FTLBS of applied torque to break them loose. My shop vise won’t stand that kind of twist.
Good luck
John

 

[Ron]

Control Valve leak

I have a d20 that is leaking hydraulic oil out of the top of the blade control valve (the up / down / tilt) and it's getting to the point it is hard to feed. It looks like an O ring should fix it, but I can't get the rod(?) out of the valve body. Does anyone have any suggestions?:beatsme

 

[darinray]

I had a seal blow on one of my blade angle cylinders today, and one of my lift cylinders has a leaking seal. Where is the best place to find the seals and is this something I can do myself without any special tooling? I've never rebuilt any cylinders before, and advice?

I have a source for those.. contact this guy at dmm@inbox.as

 

[darinray]

Can anyone please tell me what the bearing number is for a final drive on a
D20P5 is. I have called everywhere and nobody can tell me. Mine is wore off so I can't read them.:Banghead

What bearing are you talking about? Do you have a part number from Komatsu?

Darin

 

[darinray]

I have a d20 that is leaking hydraulic oil out of the top of the blade control valve (the up / down / tilt) and it's getting to the point it is hard to feed. It looks like an O ring should fix it, but I can't get the rod(?) out of the valve body. Does anyone have any suggestions?:beatsme

What machine do you have? D20 dash what? There are seals that will need replacing to fix the problem and am not real sure why you can't get the spool out of the valve body. Did you take the bottom cups off and remove these pieces? By rights you don't need to take the spool out of the body to change the lower and upper seals... you just need to remove the linkages on top and disconnect the spring below.

Darin

 

[Ron]

What machine do you have? D20 dash what? There are seals that will need replacing to fix the problem and am not real sure why you can't get the spool out of the valve body. Did you take the bottom cups off and remove these pieces? By rights you don't need to take the spool out of the body to change the lower and upper seals... you just need to remove the linkages on top and disconnect the spring below.

Darin

It is a d20-6. I've taken the linkage and a cap type thing loose from the top. I haven't taken anything off of the bottom. What is the spool? Is that the piece that connects to the lever? How to get the spring out?

 

[johnmoore]

What bearing are you talking about? Do you have a part number from Komatsu?

Darin

The one right behind the sprocket. The part number one place gave me is 06030-22215. I assume this is the part number, I told them I couldn't read mine off of the part and I don't have a manual to it. The bearing company I called said they could cross refference if I could get the number off the bearing.

 

[darinray]

It is a d20-6. I've taken the linkage and a cap type thing loose from the top. I haven't taken anything off of the bottom. What is the spool? Is that the piece that connects to the lever? How to get the spring out?

The spool is the piece that goes through the valve body regulating the flow to the appropriate circuit. You need to IF changing the bottom seals remove the bottom cap and then remove the bolt holding the spring to the spool. Feel free to contact me and I can walk you through the process and get you the copy of teh parts book and or service manual.

Darin

 

[darinray]

The one right behind the sprocket. The part number one place gave me is 06030-22215. I assume this is the part number, I told them I couldn't read mine off of the part and I don't have a manual to it. The bearing company I called said they could cross refference if I could get the number off the bearing.

Oh I see. Yeah that one is expensive but I guess what isn't. Sorry to say I don't have the number off that one. With the cost of these final drives and you want to be sure you get teh exact replacement brg sometimes is easiest to just order it from the dealer (Komatsu). If you find out a replacement one do share here. Good luck

Darin

 

[Ron]

Thanks Darin. You're great to help like you do! :thumbsup

 

[Danny B]

K5Cruz
I saw you are in OK. If you are closer to Tulsa than Dallas, I would recommend Crown Products in Tulsa. My brother in law works for Cat in Tulsa, he told me about them a couple of years ago. We have saved a chunk of money with these guys. Fixed a cylinder for a John Deere baler about a week ago for $5.35.

As the other guys, you have to disassemble and clean up the parts. They will measure and find parts, and will usually put parts on cylinder for you.

I have only had one they could not fix. Odd parts on Ford tractor.

 

[RichardPK]

Hi gps blades, Southern Equipment in Brisbane have a few D20 / D21 dozers with rippers that they source from O/S (china I think) they don't sell them, they only attache to their own 2nd hand dozers but they are really good and work on the blade control lever with a switch through an electronic hdy valve. Worth a look then maybe you can fabricate your own

 

[JeremiahSr]

Hey sethc,
I have parts books on cd's for all these little komatsu dozers. But thr center section in the rear is 30w oil. It is lube oil for the bevel and ring gear. You can adjust the brakes. In back there are little covers on back of steer clutch covers with 2 bolts in each. Remove these covers and tighten the adjuster. Then back it off about 13 notches. The brake pedal shouls be about 3 inches from floor when pressed.

 

[RichardPK]

Oh I see. Yeah that one is expensive but I guess what isn't. Sorry to say I don't have the number off that one. With the cost of these final drives and you want to be sure you get teh exact replacement brg sometimes is easiest to just order it from the dealer (Komatsu). If you find out a replacement one do share here. Good luck

Darin

Hi I am located in Queensland Australia and need to source repair, part and operator manuals for my D21PL-7E, can you help? also I have to say what a great help you are to all the guys on this thread, I have read all the posts and gained a lot of knowlege just reading the posts, well done

Richard

 

[darinray]

Hello Richard,

Yes I have those manuals so contact me through my link below so we can talk more.

Darin

 

[RichardPK]

Hello Richard,

Yes I have those manuals so contact me through my link below so we can talk more.

Darin

Hi Darin

Ok, will do, thank you for your prompt reply

Richard

 

[JOstrander]

Have a komatsu D21 p-7 .Wont steer going one way, friend of mine tried to adjust linkage under floor boards. Called komatsu they said he shouldnt have touched linkage . Want to readjust steering brake and readjust linkage back to where it should be. Any thoughts would be appreciated Thanks