Section for komatsu d20,21 and similar grey market dozers

[sick&tired]

I didnt get any replies to my earlier post, so i just went out and started working on the D31s.
I took the floor board off, i took the seat off, and the rear upper panel. I had cleaned it with a pressure washer before, but didnt have real good access in the trans area. I am going to rewash it today.
What i found was the lever which engages the steering clutches on the R side was stuck completely in the up/on position. It was rusting, and being prevented from returning by alot of hard packed dirt in that area. I took a big screwdriver and was able to scrape out alot of the dirt and clear the blockage. Then i sprayed bunches of WD40 on the joint and let it soak for a few minutes. I took the screwdriver and a hammer and started to bang on the lever to loosen it up. After about a 1/2 hour of tapping down, stepping on brakes clutch etc. I was able to finally break it free and now it will move smoothly and return where it is supposed to.
Hoping that i have fixed it somewhat, i started the tractor, let it warm up, and without replacing anything i removed, i faked a seat and tested it out in my driveway. Seems to work better now. I didn t experience the dragging problem- so far, and now it turned on R side like it was supposed too. I adjusted the brake pedal linkages a little, i think i need some more. I dont have the repair manual yet so im unsure of the exact proceedure. Anyone have any pics of what linkages i should be adjusting on the brake rods?- there are a few on each one. Darin Ray where are you buddy? You seem to know the most about these kommies.
Thanks
S&T

 

[jwar100]

Hello all, I am looking at buying a D20P-7 serial number 75056 and would like to know if this is a good model. I am in the dozer business and run older cats now. I have a customer that wants me to trade out some work for this thing, i have been wanting a smaller dozer for sometime now. Can anyone tell from the serial number what year and hp this is? thanks JW

 

[david m j]

I had a new diode put in the alternator and it fixed my starting problem

 

[catfish40]

I am new to this forum. I found it while trying to find a solution to a problem that I am having with my dozer. I have a Komatsu D20A. I let it sit up for around 3 months & when I tried to use it the right track was locked up. I pulled the seat & found that the rod in the control valve was moving properly. All of the other hydraulics are working properly I tried pulling it with my tractor to break it loose but it just dragged the whole dozer. I'm not sure what the next step is. I would sure appreciate any ideas or advice that anyone could offer to help me get it back going.

 

[jwar100]

Sounds like you have a brake locked up on the right side. Might try to see if you can move the linkages and lube them up. If you have a parking brake it may be stuck also, try moving everything and lube it up first. You could have a rat nest in the tractor as well.

 

[joemorgan]

D20 steering clutch

Hello all, I have a 1988 D20A-6, the right hand steering clutch growls when using it, can anybody tell me what causes this?

 

[darinray]

S&T....There is NO way I know the most about these komatsus but have run into problems from time to time. I don't check this site as much as I would like and sorry for not seeing your posts. The linkages are probably fine UNLESS it was adjusted prior to you owning it. To adjust the brake clearance you take the small cover off the back of the clutch housings and tighten down on the 17mm head until it bottoms out and then back off a couple turns. Keep me posted and contact me anytime via my email. Good luck and take care.

 

[darinray]

Looks like a 1992 model and they are 40hp.

 

[darinray]

Hey Joe,

Are there any other symptoms like motor bogging down or anything? It may be your clutches trying to release or your brake drum being chewed up... your slip yoke bearing bad. Best thing to do is tear it down to find out before something major happens. Good luck.

 

[joemorgan]

no other symptoms, they work fine, don't slip, just growl when you engage them under a load, been like that since I've owned it [4yrs now] I was just curious if this is normal or if they are worn and need replaced.

 

[wsw]

I have a customer here in Ontario that has one says it a great machine but a little to small for what he needs, only a few hundred hrs on it, And its going up for sale or for trade up. he wants a D4G, 550H or 650H

 

[gene0522]

Darin,

You have been such a help with our D20P. Certainly appreciate all your help. Wish everyone was as nice as you. Thanks again.
Gene & Jennifer

 

[andrewecd]

Hi,
Thought I would contribute something as I have learned a lot from searching this forum in the past few months.
I just bought this Mitsubishi for my 25 acre property.
It's a BD2H(E) model. E means wider track. Has a nice wide stance. Also has rippers which were a real selling point. Also like the clear view ahead (exhaust comes out the back! - cool)
Seller is a real nice guy who operates a D11 and a drag line in a coal mine for 30 years and he knows his stuff and how to look after it, so he also gave me a few pointers.
He loves these small dozers and could not fault it for its size....although he did say he liked this one because of the wider track (and he got the rippers fitted).

 

[Garrett]

Hello,I have issues with my d21-a5:
First I left dozer with trusted friend and now when you pull the left lever hard, it barely turns.Like the brake is doing the turning and track is still engaged.Feels like it's been like that a few hours and brake is wearing down.I didn't hear about this until recently bad enough that it's no longer working good.What a pal.
Second this past year I've had to turn glow plugs on for 15-30seconds to get it to start.Smokes black and a knock until warm.Even in 100deg weather.When I bought it I didn't have to use glow plugs unless really cold.Injectors dripping fuel now?
Third when I check transmission fluid level near brake pedal,It's dry then I put back in and recheck,it may have oil on it then if I leave dip stick out for a little longer,it will show oil level is good.Like air pressure in tank?I am supposed to check level while it's off?When running the dip stick is dry.Also if I loose power to tracks which does happen sometimes,I pull dipstick out and then put back in and power comes back.I put a qt of oil in and problem is gone.
History of dozer,it's a rebuilt in vietnam referbished unit with a pipe roll cage on it.Showed 259hr when bought and nearly 500hrs now.Was really nice looking till I used it clearing cedars on side of mountains at house.Recently I've had overheating issues so would just use it lightly and would hold temp under 210deg.I had radiator rodded out and new temp gage put on and weather has been cool so we'll see if it's fixed.It looked like hydro oil in it so I added it.I see know I should use 30SAE engine oil.I have hydro filter but don't know where to put it.long tube cartrige.I was thinking it was going to be the spin on near the batteries.Man I need some manuals I know.Komatsu dealer in dallas is awesome.That's where I bought my fuel,oil,hydro,throttle cable from.Real helpful and good people.One here in San Antonio is looking after the big boys machines with the big money.I don't blame them but sucks to have a machine people look down on.(grey market)

 

[Garrett]

One more thing, it pulls good on both sides under load but just won't turn good on left side,like brake is trying to grab it but worn down.Doesn't matter if forward or reverse.Man I'm temted to take to shop but scared of the bill.thanks for the help.CG

 

[joemorgan]

if the left track won't disengage, especially under a load it sounds like the steering clutch is stuck

 

[Ron]

Steering Problem

I was working with my D20-6 this morning all at once when I pull either steering lever the machine stops moving and a clunking noise comes from the belly. Everything still seems/sounds normal while going forward or backward (until I try to turn). I don't understand what point the steering levers have in common - unless both clutches went out at the same time.:idontgetit Is there ANY chance this is a quick, cheap fix? Any thoughts and suggestions would be appreciated.

 

[Ron]

New observation: oil is coming out of the final drive.

 

[darinray]

I think you need to check the pressures on your steering control valve to see if both sides are actually getting pressure to release the clutches at teh same time.

Is there oil in BOTH steering clutch cases? Hopefully NOT...

Make sure there is nothing obstructing the linkages that woudl cause both to be actuated...

If you push the brake pedal down all by itself (don't pull any levers and go forward or reverse) does it stop the machine or make the motor bog down?

Where does the oil leak from the final?? The sprocket seal???

 

[darinray]

Reply is in you message

Hello,I have issues with my d21-a5:
First I left dozer with trusted friend and now when you pull the left lever hard, it barely turns.Like the brake is doing the turning and track is still engaged.Feels like it's been like that a few hours and brake is wearing down.I didn't hear about this until recently bad enough that it's no longer working good.What a pal.
Second this past year I've had to turn glow plugs on for 15-30seconds to get it to start.Smokes black and a knock until warm.Even in 100deg weather.When I bought it I didn't have to use glow plugs unless really cold.Injectors dripping fuel now?
I always have to glow my older machines...

Third when I check transmission fluid level near brake pedal,It's dry then I put back in and recheck,it may have oil on it then if I leave dip stick out for a little longer,it will show oil level is good.Like air pressure in tank?I am supposed to check level while it's off?When running the dip stick is dry.Engine off and double dip stick for accurate readingAlso if I loose power to tracks which does happen sometimes,I pull dipstick out and then put back in and power comes back.I put a qt of oil in and problem is gone.Yikes... not sure on this
History of dozer,it's a rebuilt in vietnam referbished unit with a pipe roll cage on it.Showed 259hr when bought and nearly 500hrs now.Was really nice looking till I used it clearing cedars on side of mountains at house.Recently I've had overheating issues so would just use it lightly and would hold temp under 210deg.I had radiator rodded out and new temp gage put on and weather has been cool so we'll see if it's fixed.It looked like hydro oil in it so I added it.I see know I should use 30SAE engine oil.I have hydro filter but don't know where to put it.long tube cartrige.I was thinking it was going to be the spin on near the batteries.The hydraulick tank doesn take engine oil adn also has a spin on filter by batteriesMan I need some manuals I know.Komatsu dealer in dallas is awesome.That's where I bought my fuel,oil,hydro,throttle cable from.Real helpful and good people.One here in San Antonio is looking after the big boys machines with the big money.I don't blame them but sucks to have a machine people look down on.(grey market)