Komatsu D20

[Durt]

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..

 

[JGS Parts]

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?

 

[Durt]

D-20 or a D-20A

 

[crowneent]

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

 

[hayes1179]

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. hayes1179@gmail.com

 

[mitch504]

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.

 

[vinothsd]

Best message for the beginners. Thank you everyone.

For more queries contact deepam earth movers

 

[Reddog02]

Can you please e mail me the same information on d20a stearing clutches and adjustments. Reddog02@windstream.net thank you in advance.

 

[treylt]

d20p-7

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

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 treylt@bellsouth.net

 

[bulldog99]

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
rljohnson1068@gmail.com

 

[Boyzee]

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

 

[Rien]

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)

 

[darinray]

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..

 

[Rien]

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

 

[darinray]

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...

 

[Rien]

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

 

[darinray]

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..

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

 

[Rien]

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.

 

[darinray]

No it actually states 10W--> Straight engine oil 10W not multi viscosity oil...

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.

 

[Rien]

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