Section for komatsu d20,21 and similar grey market dozers

[Krackerjack9]

If your wanting or needing a ripper for a D20 or D21 they are made for those units trying to get a price if get at least 5 people and due a group buy they should come in at less than $900 total price but should know something latter on this evening

 

[Don Shilling]

Has anyone ever had a problem of squealing noises coming from the tracks and to find out the bottom rollers are not rotating, and the track chain is sliding over them, making the noise? Is it practical to rebuild the bottom rollers on a D21 or replace them?

 

[Krackerjack9]

Hmm I thought i replied to this the other day, theres a post a few pages back maybe 15 or 20 about saving the bearings from the original ones, he seemed pretty well informed on them switching them out of the rollers he bought, they must be pretty good to last over 20yrs and be better than the new ones that are in the replacement rollers
he tried putting zert fittings or something to keep the oil in the new ones but they just were not like the old ones

 

[Krackerjack9]

If your going to replace i be soaking them bolts in some penatrating oil a good week before replacing them or weld on some extensions to get some leverage the sides of the bolts will be pretty much worn off might have to either take off the front idler wheel to get enough slack in the tracks to take them off or if you got a a good 100ton track press to push out a pin I had to get Komatsu come out and they ended up taking the tracks to the shop to press the pins in the track press they had on the truck couldnt even budge it guage topped out at 35,000psi and nothing except groaning from the pump

 

[Don Shilling]

We just raised the front of the machine and blocked it up. That gave enough sag in the track to remove the bottom rollers. New ones came in today. Purchased all new bolts and cleaned the threads in the mounting holes. I'll use never seize going back together. I'll start a thread with pictures when completed .

 

[Krackerjack9]

thats great should never have to deal with them again, supposed to get a good 2500 to 3000hrs out them rollers

 

[Don Shilling]

This machine has always squealed since the day I received it. It's amazing how "quite" it is now!

 

[g_man]

What did the old rollers look like Don. They must have had a flat spot worn into them ???

gg

 

[Don Shilling]

What did the old rollers look like Don. They must have had a flat spot worn into them ???

gg

Two were recent replacements, the other 8 seemed to have internal failure of which 3 of those seemed to have severe internal failure. Why only 2 were replaced within the previous 100 hours is unknown. All should have been replaced at that time considering how easy they were to replace.

 

[Ricky Hill]

how much pressure in komatsu d20 s-5 loader hydrolic pump

 

[oldhousehugger]

Has anyone ever had a problem of squealing noises coming from the tracks and to find out the bottom rollers are not rotating, and the track chain is sliding over them, making the noise? Is it practical to rebuild the bottom rollers on a D21 or replace them?

When I got my D20PL-6 from the guy in Sulphur Springs it had just had new tracks and sprockets installed. What they didn’t replace were all the rollers which needed replacement desperately. The worst ones had the entire outer lip of the roller worn thru and fallen off so it rattled around as the track moved. One of those things they don’t point out to you as your writing the check. I replaced all of the rollers with aftermarket and those have lasted 10 years with only one leaking oil so far. Having rollers the correct radius is crucial to reducing vibration. I rebuilt the 2 front idler wheels with bearing and shaft parts from the old rollers i'd replaced. They are the same internally. If you do put zerk fittings on your new rollers the manual says use SAE 30 wt engine oil inside the rollers. My question is has anyone come up with a good way to inject 30 wt with a grease gun into the rollers. I’m thinking it may need a long syringe type applicator to start injecting oil way into the back of the shaft. Yes I did used a light grease in mine BUT I now worry about it being too thick to lubricate the floating seals properly. Many warnings elsewhere on using grease instead of oil.

 

[oldhousehugger]

how much pressure in komatsu d20 s-5 loader hydrolic pump

Manual says pressure is 155kg/cm^2 which converts to 2204.6 psi

 

[Don Shilling]

When I got my D20PL-6 from the guy in Sulphur Springs it had just had new tracks and sprockets installed. What they didn’t replace were all the rollers which needed replacement desperately. The worst ones had the entire outer lip of the roller worn thru and fallen off so it rattled around as the track moved. One of those things they don’t point out to you as your writing the check. I replaced all of the rollers with aftermarket and those have lasted 10 years with only one leaking oil so far. Having rollers the correct radius is crucial to reducing vibration. I rebuilt the 2 front idler wheels with bearing and shaft parts from the old rollers i'd replaced. They are the same internally. If you do put zerk fittings on your new rollers the manual says use SAE 30 wt engine oil inside the rollers. My question is has anyone come up with a good way to inject 30 wt with a grease gun into the rollers. I’m thinking it may need a long syringe type applicator to start injecting oil way into the back of the shaft. Yes I did used a light grease in mine BUT I now worry about it being too thick to lubricate the floating seals properly. Many warnings elsewhere on using grease instead of oil.

If you do install lubrication fittings on the rollers, use "button head" fittings and get a dedicated oil pump gun with the button head adapter. The button fittings are so much easier and cleaner to use than a zerk fitting.

 

[oldhousehugger]

Button head fittings are easily found on the net. Where would you direct me to start looking for a hand operated high pressure dedicated oiler pump? I’ve thought of trying to convert a grease gun to an oil gun but it would be a lot of work.

 

[Don Shilling]

Button head fittings are easily found on the net. Where would you direct me to start looking for a hand operated high pressure dedicated oiler pump? I’ve thought of trying to convert a grease gun to an oil gun but it would be a lot of work.

Here's a link to a hand pump that might be suitable.
https://www.americanlube.com/category/oil-pumps-portable-packages-gear-oil-dispensers/

 

[oldhousehugger]

If your wanting or needing a ripper for a D20 or D21 they are made for those units trying to get a price if get at least 5 people and due a group buy they should come in at less than $900 total price but should know something latter on this eveningView attachment 227624

IMHO my little D20 would stop dead "in its tracks" with those massive rippers in the ground. Perhaps the D21's with the hydrostatic transmission can apply the low end power needed to pull that thing.

 

[oldhousehugger]

Here's a link to a hand pump that might be suitable.
https://www.americanlube.com/category/oil-pumps-portable-packages-gear-oil-dispensers/

I emailed them for pricing and availability

 

[1970ChallengerT/A]

My steering clutch throw out yoke appears to be froze. Have the clutches out and can't move the lever. Also, the four studs that compress the clutches are extended so I can't reinstall the clutch pack. Anyone have this issue or know how I can free this up?

 

[Don Shilling]

My steering clutch throw out yoke appears to be froze. Have the clutches out and can't move the lever. Also, the four studs that compress the clutches are extended so I can't reinstall the clutch pack. Anyone have this issue or know how I can free this up?

You will have to remove the pinion gear flange. The four finger collar rides on a machined portion of the flange and this is where it is sticking. Penetrating oil and judicious hammer action is your only option.

 

[1970ChallengerT/A]

Thanks, the photo helps. I have it soaking now, have sprayed it the last two days. Will try to break it loose this weekend and let you know how it goes.