The level shows between the two marks before starting. After running it for awhile it acts as is it has built up pressure.
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Section for komatsu d20,21 and similar grey market dozers
- Thread starter rangerfreak
- Start date
The level shows between the two marks before starting. After running it for awhile it acts as is it has built up pressure.
sick&tired
Active Member
Darinray- Your the man!!!
Thank you!!
That is just what i was looking for.
From my research i thought sae 30w was in order but i wanted to be sure.
Thank you!!
That is just what i was looking for.
From my research i thought sae 30w was in order but i wanted to be sure.
ajl7742
New Member
Roller Question
First of all, let me say thanks to everyone for all of the terrific information posted here. I bought my D21P-6 about a year ago and have found just about everything that I needed to know so far about it right here.
I use it primarily around my property in central Louisiana to make trails and clear food plots. It has been quite an impressive machine for its size. Towards the end of the summer I noticed heavy vibrations when tracking on the roads. It has been very dry this year so it could be that the vibrations became much more noticeable on the hard packed dirt as opposed to softer ground. The panels will literally shake to the point that some bolts have loosened up while tracking on hard pack.
It does have the wide swamp pads on it but I never noticed this heavy of a vibration before, not even on my driveway at home. Is this normal on these machines when running on a hard dirt surface? I am new to tracked machines so I wouldn't know where to start if I thought that there was a problem. Any insight would be helpful. Thanks again for info posted here. Great forum!
Adam
First of all, let me say thanks to everyone for all of the terrific information posted here. I bought my D21P-6 about a year ago and have found just about everything that I needed to know so far about it right here.
I use it primarily around my property in central Louisiana to make trails and clear food plots. It has been quite an impressive machine for its size. Towards the end of the summer I noticed heavy vibrations when tracking on the roads. It has been very dry this year so it could be that the vibrations became much more noticeable on the hard packed dirt as opposed to softer ground. The panels will literally shake to the point that some bolts have loosened up while tracking on hard pack.
It does have the wide swamp pads on it but I never noticed this heavy of a vibration before, not even on my driveway at home. Is this normal on these machines when running on a hard dirt surface? I am new to tracked machines so I wouldn't know where to start if I thought that there was a problem. Any insight would be helpful. Thanks again for info posted here. Great forum!
Adam
oldhousehugger
Well-Known Member
D20 with stuck main wet clutch
OK so I haven't used the D20 all summer. Yesterday I went to check fluids and otherwise winterize it and when I started it the clutch pedal had no effect. I pulled the floor plate and all the levers and inertial brake are working as designed so I am assuming the double wet disk clutch has somehow rusted??? to the flywheel.
I can start it in gear because of some previous rewiring and so I tried pushing against a Mesquite tree with no effect except to remove some bark and stall the little engine. When I got back to the house I went thru the manual which of course does not cover whats wrong when wet disk clutch will not disengage. I did however read about how to remove the clutch from machine. In there it says to insert 3-150mm x 10mm x 1.5mm/thrd (5") bolts with nuts and then tighten the nuts down about 10 mm (3/8"). I am figuring I may be able to insert those bolts through the access plate on top of the clutch housing and release all the spring pressure on the plates. With that done, if the bolts don't stick out to far and I can turn the clutch case around without tearing something else up in the bell housing, I will try jarring it once again and see if that works.
The biggest problem is access to the clutch drum. I may need a mirror to see whats going on in there thru the access hole.
The little old girl worked fine last spring when I parked her and I have never heard of a wet clutch seizing like this.
Any other ideas and experiences would be great to read.
OldHH
OK so I haven't used the D20 all summer. Yesterday I went to check fluids and otherwise winterize it and when I started it the clutch pedal had no effect. I pulled the floor plate and all the levers and inertial brake are working as designed so I am assuming the double wet disk clutch has somehow rusted??? to the flywheel.
I can start it in gear because of some previous rewiring and so I tried pushing against a Mesquite tree with no effect except to remove some bark and stall the little engine. When I got back to the house I went thru the manual which of course does not cover whats wrong when wet disk clutch will not disengage. I did however read about how to remove the clutch from machine. In there it says to insert 3-150mm x 10mm x 1.5mm/thrd (5") bolts with nuts and then tighten the nuts down about 10 mm (3/8"). I am figuring I may be able to insert those bolts through the access plate on top of the clutch housing and release all the spring pressure on the plates. With that done, if the bolts don't stick out to far and I can turn the clutch case around without tearing something else up in the bell housing, I will try jarring it once again and see if that works.
The biggest problem is access to the clutch drum. I may need a mirror to see whats going on in there thru the access hole.
The little old girl worked fine last spring when I parked her and I have never heard of a wet clutch seizing like this.
Any other ideas and experiences would be great to read.
OldHH
oldhousehugger
Well-Known Member
ajl7742
I got my D20 from a guy over in Sulfur Springs Texas. When I got it onto the job I thought it really rattled a lot. I used it that way for a few days and then for some reason I lifted the tracks off the ground with the blade and noticed that the lip on the roll of the rear most roller had worn completely off the roller. Another roller was seized and the track was just grinding it down. I talked it over with the wife and we decided to bite the bullet and replace them all since there wasn't even one which was even close to allowable spec.
I managed to find aftermarket rollers and bought a complete set of 12. I believe they take a 22 mm socket and a very long breaker bar with a cheater. Somewhere on the web I have seen a reference to maximum allowable wear for rollers and track but do not have the link handy.
Here is link to another article on that topic.
https://www.heavyequipmentforums.com/showthread.php?p=31049#post31049
It was amazing how much less vibration there was after changing them out.
As an additional note, when I had it up changing rollers I noticed the subframe member on the left side under the fuel tank was cracked several places and I took it out and rewelded it it while the machine was down for repairs. The vibration had apparently cracked the frame from long neglect.
OldHH
I got my D20 from a guy over in Sulfur Springs Texas. When I got it onto the job I thought it really rattled a lot. I used it that way for a few days and then for some reason I lifted the tracks off the ground with the blade and noticed that the lip on the roll of the rear most roller had worn completely off the roller. Another roller was seized and the track was just grinding it down. I talked it over with the wife and we decided to bite the bullet and replace them all since there wasn't even one which was even close to allowable spec.
I managed to find aftermarket rollers and bought a complete set of 12. I believe they take a 22 mm socket and a very long breaker bar with a cheater. Somewhere on the web I have seen a reference to maximum allowable wear for rollers and track but do not have the link handy.
Here is link to another article on that topic.
https://www.heavyequipmentforums.com/showthread.php?p=31049#post31049
It was amazing how much less vibration there was after changing them out.
As an additional note, when I had it up changing rollers I noticed the subframe member on the left side under the fuel tank was cracked several places and I took it out and rewelded it it while the machine was down for repairs. The vibration had apparently cracked the frame from long neglect.
OldHH
I am battling the same problem, d20 sat for 3 months and I got the same results as you. I have tried the same things as you with no success. I dont have the books and see no way to go through the small access hole on top.I have to kill it to change gears , it was doing great before it sat up. This thread is not very active but I hope someone , gives help soon. I sure like the little dozer and want to use it again. Also , where might I get a shop manual or copy, paper or CD . Good luck ,and if I figure something out , I will post it immediatly.
ajl7742
New Member
Thanks OldHH,
That is what I was afraid of. I am going to pick it up this weekend and check them out. I have a feeling that a few may be shot. I need to do a few on my KX91 excavator anyway so I guess I will be getting a little hands on experience soon.
That is what I was afraid of. I am going to pick it up this weekend and check them out. I have a feeling that a few may be shot. I need to do a few on my KX91 excavator anyway so I guess I will be getting a little hands on experience soon.
oldhousehugger
Well-Known Member
On the roller topic, I have read you can build the rollers up with weld but then you may loose the heat treat. After trying to turn the guts of one into something else on the lathe I found they make them really really hard. I ended up throwing the part in the bottom of the BBQ before a long cookout. The next day after everything had cooled down it could be worked with my old noncarbide tooling. You would definately have to disassemble each roller and then weld it and reharden it and then reassemble it.
The manual I got for the D20 was a reprint of marginal quality from SSB (bad picture reproduction). The diagram on page 24-2 shows that there is room to insert a stud thru the access plate hole and thread it into the pressure plate.
You will notice that there is almost no clearance between the pump drive gear and the pressure plate case so I would be very careful turning the engine over so it doesn't accidentally start and tear up everything.
The manual says that the way you have to disassemble the pressure plate from the flywheel is insert the 10mm x 1.5 studs and then crank down on a captive nut enough to compress the springs and pull the pressure plate back off the clutch discs.
i'm thinking that by pulling the pressure off the clutch discs maybe I can loosen the rust that is sticking them together. Then with the transmission in neutral insert a bar to twist the drive shaft which would then try to rotate the discs which would immediately break them loose. Oh course! I'm being optimistic!
I made a copy of the page which i will try to insert as a jpg
If you get to it before I do let us know how it works out. My machine is 2 hours away in the middle of a field north of Waco and me and the shop are here in dallas.
I hope to get back down there by the end of the week.
OldHH
The manual I got for the D20 was a reprint of marginal quality from SSB (bad picture reproduction). The diagram on page 24-2 shows that there is room to insert a stud thru the access plate hole and thread it into the pressure plate.
You will notice that there is almost no clearance between the pump drive gear and the pressure plate case so I would be very careful turning the engine over so it doesn't accidentally start and tear up everything.
The manual says that the way you have to disassemble the pressure plate from the flywheel is insert the 10mm x 1.5 studs and then crank down on a captive nut enough to compress the springs and pull the pressure plate back off the clutch discs.
i'm thinking that by pulling the pressure off the clutch discs maybe I can loosen the rust that is sticking them together. Then with the transmission in neutral insert a bar to twist the drive shaft which would then try to rotate the discs which would immediately break them loose. Oh course! I'm being optimistic!
I made a copy of the page which i will try to insert as a jpg
If you get to it before I do let us know how it works out. My machine is 2 hours away in the middle of a field north of Waco and me and the shop are here in dallas.
I hope to get back down there by the end of the week.
OldHH
D3DaveC
Well-Known Member
On the topic of a wet clutch sticking together; I had an old D2 Cat with a wet main clutch. When I first brought it home the clutch would not release therefore I couldn't shift. I drained out the old oil, loosened off the clutch adjustment and filled the clutch housing with diesel fuel(maybe should have been kerosene?) and run it for awhile. Drained the diesel and let it drip out good, filled with correct amount of new oil and it worked good. Old oil can sometimes stick certain things together.
Thank you for the picture of the clutch assy. Great news!!!!!!!!! after parking the dozer pointing uphill ( I dont know if that had any thing to do with it ) While I was trying to fix it I adjusted the shaft brake and added 2 qts of new fluid. I started my d20 in gear and backed it up , then once again I started it up in forward gear.... thought I would bump a stump once again , pushed the clutch in as far as I could without engaging the drive shaft brake and ran at the stump from 10 feet . It worked !!!! It works better now than ever and shifts smooth with no grinding. Keep bumping that stump . Good luck ! Nick
Thank you Jesus ! I really didn't want to go into that clutch housing.
Thank you Jesus ! I really didn't want to go into that clutch housing.
With so much talk about clutches I think you guys have given my D20P-7E a clutch virus. My machine was operating great until suddenly when clutch pedal was depressed it became extremely hard to engage or come back dis-engaged. I have removed floor plate where it appears all is normal no bent linkage, I was able to limp back to shop with force applied to clutch pedal. I cant tell by diagram if unit has a T.O bearing that may be seized to shaft? Any thoughts would be appreciated.
TY
TY
No, what I meant was you needed to be superman to depress or release the clutch pedal. I have found the problem lies where the clutch attachment rod connects with the fulcrum lever then to the clutch assembly. Inside the fulcrum lever is a needle bearing that cannot be greased, once it goes dry it is metal to metal on shaft which then caused it to bind resulting in pedal not wanting to move. The bearing is $9.00 #06124-02020 from Komatsu. If you are noticing the pedal not retracting quickly, drive shaft spin-down time excessive (as adjustment rods wont extend fully) or the clutch return spring breaking your problem may be this bearing which cant be seen until it's dissembled. I have 3400hrs on my machine.
oldhousehugger
Well-Known Member
As a followup on my earlier post, the 10 mm bolt idea pulling on the pressure plate idea worked to pull the outer pressure plate but did not affect the inner one. I was able to use it to take the pressure off the outer clutch plate but the inner disk and plate are still frozen up in there and it looks like I will have to remove the bell housing and pull the pressure plate etc. I tried again pushing stuff with the machine but that didn't work. With the pressure plate released I tried rocking the driveshaft with a big wrench. Even though I could feel the outer disk loose in there, it was still bound up. In disgust, I left the clutch pedal depressed with a 14 inch chunk of firewood. Maybe by the time I get back it will have magically come loose in there. Otherwise, back it up on some timbers, slide a piece of 28 inch wide plywood under to roll the transmission jack on and drop the sucker. This is why impact wrenches were invented. Maybe I should replace my left steering clutch while I’m at it. I pulled the alternator at the same time because I’m not getting any charge.
OldHH
OldHH
Frank Dozer
Well-Known Member
My 1985 Komatsu D21A-5, shuttle shift, 1800 hours, hasn't been used in about 10 months. I've started it several times for about 10 minutes in those 10 months just to check the batteries, but hyave not used it. It's stored inside 24/7. Well yesterday I started it to move it outside to get my trailer out which was parked behind it and it went forward just fine. To get it out of the garage, it has to go down a 3" step then within 4' of flat then has to go down an 8" step. All went well. I got my truck, pulled out the trailer then started to back the Komatsu back inside. It went in reverse OK, but when I got to the8" step, Komatsu backed to it then just sat there. I had to go forward then backward 2 times to get a slow running start to get up the step. I was going to use it next week to do a few things, but I don't want to get down to the lower field and find out I have no reverse. What is going on? The temperature was about 22 degrees? was the trany fluid just cold or do I have a bigger problem??
22 degrees ??????? That little dozer is telling you to stay inside where it is warm. It is 70 degrees down here today . I always wonder why you guys live up north........ If your oil level is low and the cold temps cause it to contract, it could just be acting like low clutch fluid. We all tend to freak out when these machines act up , but it is usually a simple fix. Good luck
Last edited:
joemorgan
Member
Hello Glock, I had the exact same problem with my D20, I sprayed some WD40 at the clutch pedal pivot point, this helped for about 15 minutes, I then sprayed it with PB Blaster, been working fine since. Hope this helps
PawPaw
New Member
I am brand new to this site and I need help. I have a D21A (not sure about other numbers). My left side track does not pull whwn making right turns or pushing. Any help is appreciated.
darinray
Charter Member
Your left side clutches are either bad or oil soaked. Need to tear it down to find out exactly. If you just got it maybe you could be LUCKY and find that the linkage is not adjusted right or something is binding it allowing the left side steering valve to be partially disengaging BUT after finding this play the lottery because that woudl be luck. 
Contact me if you need more info.
Contact me if you need more info.