I see alot of Komatsu D20 for sale for 13-20,000. I was wondering what this machine is capable of. Can you grade out a half acre lot with some dump truck piles, and how would you compare it to a skid steer? Is it so under powered at 40 hp that you are sorry you baught it? How would you compare it to a 50 - 60 hp tractor with a box blade?
We rented one to do a final grade on our property. It's kind of underpowered and a little too light. I found that it pushed a sufficient amount of dirt with the throttle turned up pretty high, but this is bad for fuel consumption. I don't have much experience with dozers, but with the throttle at a normal setting I had to make several passes to spread out truck loads of dirt. It's a good weight for finish work, but not for any mass earth moving. I would rather own a 15,000lb to 18,000lb dozer and rent a small one for the jobs that need one. A large skidsteer will probably push more, but tracked machines are generally better for riding over uneven terrain and leave a nicer finished grade. Track systems for skidsteers may help with this, but that is an added expense on top of the machine cost. Hope this helps.
It's hard to compare a dozer to a tractor or a skid steer, tracked or wheeled. Almost any dozer, even a small one will outproduce the above machines when it comes to pushing dirt, clearing, or cutting in driveways etc. But on the flip side, that's all a dozer can do. Skidsteers and tractors have a huge variety of attachments available that can do almost any job. They also do not rip everything up, including roads, yards and driveways like a dozers single grousser steel tracks. You can also not really compare the horsepower of dozers to that of other machines. All the newer larger skid steers have higher horsepower than small dozers, but it is used differenly. My Cat D-3 only has around 70 horses, but it is around #15,000 pounds, and it will spin its tracks and never stall when against something it cannot move. What type of machine you need really just depend on the kind of jobs you'll be doing.
Thanks for the imput woberlin
its just a wee dozer, lad! The series 20 Komatsu is a 7,000 pound dozer. It is a nice small dress dozer but the controls may take some time to master. It, like the skid steer, should not be confused with earthmoving equipment. As someone mentioned, the torque figure tells far more about how a machine pushes than the HP rating.
Comparison I have a Ford 4600 (55 HP) with a heavy duty 6 ft box blade and my little D20AG does a much better job of moving dirt. so much so I built a three point hitch for the back of the D20 so it can pull the box blade. When the box was about half to 3/4 full the tractor would start to spin and not move any more unless I started to pull just what was in the box. with the D20 pulling it I can spill it ove the top. Plus the D20 can pull with the ripper teeth al the way down and the box tipped slightly forward (deepest rip). I almost ready to trade the tractor for a backhoe. But I'd have to replace the mowers for the tractor with a ZTR. Brian Baby dozer owner
Do you have pics of the ripper and attached box? I've never seen any on a D20. Sounds like a nice addition for some light work. My D20p specs out just under 9000lbs. It pushed lots of dirt with traction so power is no issue. But without traction it just spins and I can barely load up the blade. I plan to weld some flat bar to the swamp tracks to resolve that issue.
Trade-offs Sure they're light dozers but you also can pull them on a relatively small trailer with a 3/4 ton pickup. For light clearing, I rarely have run mine much faster than an idle and it does a great job in low gear. Low gear is fine with me too; I'm new to this dirt pushing thing so I don't like going too fast plus, I've been working in some areas that were pretty tight. I can see how smooth tracks could be a problem. Fortunately, my D20 has had rebar welded to the tips of the pyramid pads. I'd sure like to see how you did that ripper too. having the ability to stick a 3-pt implement on the back wouldn't be all that bad.
D20 with 3 point box blade Here is a picture of the lift arms and the cylinders. I've redesigned the lift system because with this configuration the single valve lets the implement twist instead of staying level. I'll have to change the hydraulic valve to a two circuit (twin valve) so each piston has its own spool. If you can see it just below the second (electric) hydraulic pump are mounts for the upper link of the 3 point system. I'm trying a single piston upper link and stablizing bars from the implement's upper link to the center of the lower arms. That should stop the see-saw action. Next time I have the blade on the dozer I'll shoot some pictures. Brian
Nice work! Thanks for showing it!
rubber tracks dozer i like it. when your spreading loam in a subdivion and you haveto travel up the street to the other lot one word peeerfect
You can grade out 50-100 acres if you have the time - the D21 will outperform a skid steer 50 to 1 - you can't even compare the two machines. In addition, the 6 way blade on the D21 puts it in a new category when compared to a box blade. Forget the tractor or skid steer. Get the D21 do your job and when your done - put it back on the market and chances are you won't lose a dime. Thanks
I have a D21E-6 and love the machine. I purchased it for the sole purpose of work around my parents property because our New Holland Tractor with loader and backhoe was inefficient for the work as was a 3 pt. hitch woods back blade. I had previously looked at renting a John Deere 450D from Sunbelt rentals but the dozer was too big for some of the areas I needed to work and renting it was was cost prohibitive for the length of time I would have needed it. Long story short...I found a 1991 D21E-6 with the 3-speed powershift tranny for $13,000 and it took me all of a day to decide to buy it and I haven't looked back. My owners manual says the machine weighs 8818 pounds and it has a drawbar pull of approximately 9000 pounds. This thing is easy to use and can move some dirt!!! My only issue right now is that I need new grouser bars on my tracks. One suggestion as far as moving larger quantities of dirt is to have the trucks tailgate the dirt if possible instead of just dumping in piles. It saves you some work of having to move the dirt as far and you spend less time knocking the piles down. On Edit: I can run the dozer for 8-10 hours before I need to add fuel. My fuel tank is 15 gallons and I run the engine at full throttle so that I don't lug the engine.
D20 The D20 has a gearbox,so you get lots of power to the tracks.You'll make a great little dozer out of it with Standard dozer plates & Ripper/Scarifier on the rear. The rubber & swamp tracks are OK for their applications,but standard track plates will give real dozer performance.The difference between swamp plates & standard shoes is vast,when doing dozer work like excavating.There are many track suppliers out there. You'll need a little time to level a truckload of dirt,but the machine will push dirt,clear small scrub & excavate a shed site (if ripper fitted).They also pull a decent sized fallen tree....all on low fuel usage. Jim
The rubber tracks I put on my D20 have a tractor style tread and grip on most dry surfaces better than the original tracks did. I would spin tracks and dig right in at half throttle with the old tracks. Becaus they only linked to the drive sprocket on every other tooth I was always having problems. The new tracks will stall the engine at 3/4 throttle of you get up against something that doesn't want to move.
Komatsu D20P-5 Steering clutches Does anyone know when replacing the steering clutches on a Komatsu D20P-5 do you have to remove the final drive or can you pull the brake drum/clutch housing assembly out after unbolting both sides? I see it has bolts on the sprocket side and the transmission side, but are there splines in the middle, or will the whole assembly slide up? I have to replace the clutches on both sides? Any input or help would be great. Thanks! Pete
I can fax you or email you the procedure. The clutches and brake band come out as a assembly from the top of the machien by removing seat and linkages and unbolting the top housing. NO taking tanks off or removing final drives. Contact me anytime. Darin
That would be great if you can e-mail me the procedure. My e-mail is [email protected] I haven't taken this apart before and didnt want to take apart more than I had to. Thanks for the help! Pete
email sent..make sure your spam filter doesn't block [email protected]
can anyone tell me the measurement of the rubber track for the D20??
what is the size of the track???? is it 300x71x72?? I have a customer who barely speaks English and cannot figure out how to find the size and the Komatsu dealer is not any help.. I cant afford freight if its wrong..
do you mean for the D20 or the D21 dozer?
D-20 or a D-20A
There are 6 different models for a D20- It can be 2 different sizes. I think there is a company in the east coast, NJ that deals with those. Summit Supply
If there is anyway u could email me the procedure on the steering clutches it would be awesome. I have a 97 model d20p5 that needs new clutches. And I do t have a clue where to start. Even some info on a good place to order parts would be very helpfull. Thank u. [email protected]
Look up at post 19. Darin Ray is a specialist in these machines and is very helpful. He sells parts for them and repairs them. His website is at the bottom of that post.
Best message for the beginners. Thank you everyone. For more queries contact deepam earth movers
Can you please e mail me the same information on d20a stearing clutches and adjustments. [email protected] thank you in advance.
d20p-7 i recently purchased a D20p-7 (my first dozer) and also need to rebuild steering clutches. Could you please send me this procedure also? any help is greatly appreciated [email protected]
Hello gentleman. I am new to all of this including operating a Komatsu d20S-6 crawler loader..I love my little machine....she's a little rough on the cosmetics but runs great....I haven't been able to find or afford the one I have found service manual..she'll turn right fine bit pull left lever and she stops....a little jerk to left then stops instantly...I know there is water in housing but need to know where tho drain and how to adjust brakes and clutches....any help greatly appreciated. Bulldog99 [email protected]
Hello everyone, just joined today, So if I get this wrong please be easy on me, mybe just a good horse whipping. I have just purchased a 1970 approx Komatsu D20S-4. What I am trying to find out is a PTO able and how would you fit one as it seems to have the plate, but don't any more than that, Cheers hope you can help
Darin, Being new here now but made a lot of use of this site by reading owners experiences. Just finished a sort of revision and cleaning of one of the steering clutches of my Komatsu D20S-5 track-loader. This due to the familiar "not steering at one side" issue. All parts are going as new again now and have been mounted back, however I am wondering how to de-air the hydraulic steering system? Noticed a significant amount of pressure on the system when the engine is running. Logical because this pressure has to press the 8 springs inside the clutch drum. Found a little squared shaped screw (7mm) at the hose connection on the top of each of the hydraulic cylinders (which pushes the clutch rod). Has this little screw a 'bleeding" function like with cars or is there a different way to get the air out of the hydraulic steering system. Assuming this is the issue of not having a clutch now after mounting all together. Can you please advise, regards, Rien (posted this one as well on the "grey market" thread)
Hello and welcome to the forum.. Rien sorry to hear of your troubles especially after going in to fix the unit. ANyway the hydraulic (both the hydraulic for loader function and the hydraulic of the steering cluthes) bleed themselves generally. Just cycle them by operating the functions of each system.. You actually hear the motor loaded up from a hydraulic pump? The clutch is just a normal clutch and shouldn't be affected by hydraulic pressure. It's engaged normally and only released when you pressure the pedal and actuating the linkages... Do all your loader functions work normally and return to neautral position? Your machine won't pull when you put it in gear at all.. Any gear? Keep me posted..
Darin, Many thanks for quick reply. After remounting the steering clutch the tractor only reacts on the break function of the pedal, not at the clutch function. Which is combined because of no levers on this model. That made me think of having air in the hydraulic system because all was disconnected (hoses, cilinders). And while releasing this little (7mm squared shaped) screw air and oil came out. So to disengage, when pressing the pedal, this cylinder should push the rod which pushes the plates inside the drum, however I assume that is not happening, because only the engine reduces power due to brake band tightening, not to clutch function (as that should not reduce engine rpm's and power). Loader functions all work and tractor is moving when shifted in gear, however still not steering. Now at both sides... Regards, Rien
Oh when you said clutch I was thinking the main clutch nbot the steering clutches.. Yes I have had that happen ONCE when I bought a machine from a guy and he delivered it and then would not steer. He looked confused but thought for sure he was just a crook. Long story short I pulled the little plug you are referring to and started steering again. Now that I know you are talking about the steering clutches not releasing we should be on the same page. Try the bleeding part on both sides and make sure your clutch oil level is at normal range. This is the pump that release the slip yoke inside the steering clutch case.. How did the steering clutches look and the steel plates. Where they swelled from rust. Did you adjust the actuating bolt to be sure it was 121mm from the center of the machine? When you assembled the clutch packs did you tighten them down evenly and make sure the tubes went through the inner drum. When you place the inner assembly inside the outer brake drum did it look like it was relatively level (not perfectly level but close)? Talk to you later...
Darin, The steering clutches looked pretty ok. One was dry and functioning, on the other, (the not steering side) parts were caught by some rust. But still very good and easy to clean with a steel brush. Almost no wear and tear as tractor ran only 1200 hours. Inner plates were all ok, After having them all apart I grinded them slightly with fine sandpaper. The steel plates in between were rustfree, also these have been slightly touched with sandpaper. Only the final covering lid, which moves over the top splines of inner drum when clutching, was stuck to that inner drum and for that reason the plates unreleasable and did not trigger any steering (the issue!) Soft hits with a small hammer made it come loose. Thoroughly cleaned and greased with some copper grease, as written before, made it moving smoothly again like new. The 121 mm distance to machine center will be close. I guess this may vary a bit as the cylinder will adjust the last mm's..? Which "tubes through inner drum" do you mean Darin? The ones inside the springs? The part "clutch oil level is at normal range. This is the pump that release the slip yoke inside the steering clutch case" is not fully clear to me. Inner drum inside the outer brake drum leveled somehow when mounted and is equal to working side. Can you please inform me what sort of oil is used for these hydraulic clutch cylinders left and right? Is it hydraulic oil, ATF or brake oil (dot 4) and and approx. how much? The dipstick of the reservoir is situated just below the right brake pedal. Perhaps a strange question but each and every word/character is Japanese on my tractor. Thanks and regards, Rien
Oh ok. The 121mm is plus or minus 1 mm so it has to be pretty close to that.. The steel tube that go inside the springs yes.. If they are hung up (not through the hole) it will cause problems for sure.. It's sounds impossible to mess up but has happen before on occasion. The main clutch pump provides the oil (10w engine oil) for releasing the clutches via the steering clutch cylinder..Manual states 6 liters of oil... Good luck and keep us posted..
Great. So just the regular (car) engine oil? Like 10W40 or 15w40? Just to be on the safe side as I do not want to mess up the machine.
No it actually states 10W--> Straight engine oil 10W not multi viscosity oil...
10W equals hydraulic oil? Can find it "here" only as fork-oil for motorbikes
hmmm... Someone should have it.. Autoparts store or tractor store... Good luck...
The D20S-5 tractor rolls again and steers like new! Thanks Darin, your advise was very welcome. Found the 10W oil at a local (Dosan) construction machinery dealer this afternoon. Re-adjusted the rod - center machine measurement (121mm) and got the cylinders de-aired in less than a minute. Next is mounting all plates, brackets and seat back in place and then playing time! Regards, Rien
Nice. glad to hear it worked out for you. Not fun time..
There's a commercially available three point hitch that mounts into a 2" receiver that could be adapted or copied: http://www.t-pointlift.com/T-Point-Lift-Vehicle-SUV-UTV-3-Point-Hitch.html
Hey everybody,i'm new at this I don't know if I'm in the right place I have a BD2g that will not turn right both tracks seem to dig well while trying to move dirt just won't turn Right,I would appreciate any help. Thanks, Ken
You'd probably have more responses if you made your post in its own thread. I have a BD2G II also. If you need pics or some sort of measurements of a BD2G that works you can ask me.
D’day All, I have a 1980s Komatsu D20S-5 track loader, and am looking for clutch adjustment specs, if anybody has them. I have the adjustment rod specs for a Series 6, but these are different to the 5! Anybody out there able to help? Cheers, Rob
Hello D20 drivers, Being a proud owner of a 1979 Komatsu D20S-5 track loader which needs some engine parts. Who can help me (or guide me) in getting cilinder head parts. The engine type is 4D94-2 and am looking for a rocker arm, valve rod pushers and valve springs. Thanks for your support. Regards, Rien
I have a D21a-7 and it's excellent for pushing over trees up to 10-12". All my dirt moving is short push and trim work. I don't think there is anything available that I would consider trading for. Fuel economy is excellent and it's a "crank er up, get er done" machine!
If there is water in the steering clutch housing you really need to schedule a remove and rebuild session. Drain plug on bottom of case, use 1/2" impact driver to remove.