Komatsu D20A-6 ?

[GuglioLS]

I did a bunch od dozer maintenance @ 1748 hours on the proof meter. I am documenting this here so that I can print it out and and place it in my owners manual.

First thing was to replace the muffler - it was rusted out, leaking all over the place, causing soot deposits all over the engine compartment. The four nuts holding it on are shot. They came off no problem after heating them up with the Oxy-Acetylene torch:

Here you can see it rusted all the way through from the inlet to the outlet. There are supposed to be baffles in there:

Here is a side by side comparison of the old muffler and new one:

The gasket between the manifold and muffler is a one time use made of paper thin steel. So I made a new one out of a 1/16'" thick copper plate I had laying around:

I replaced those rusted out and torn up nuts with some nice new hardened steel ones:

This is what it looks like now :

This concludes the muffler replacement procedure.
Larry

 

[GuglioLS]

When I had removed the muffler, there was easy access to the valve cover. So I removed it to check the valve clearance. The rocker arm is pretty black with sooty oil deposits. I will change the oil now and at 50 hour intervals until this clears up.
The valve lash clearance is 0.3 mm for both intake and exhaust. There is a mark on the front pulley for TDC. All I had to do was rotate the engine using a ratchet wrench, then look for the #1 intake valve to open, then close then look for the TDC mark. In the manual it states I can adjust 4 valves at that point, the ones I can adjust are in a chart printed in the manual. After those 4 valves are adjusted, rotate 360* to TDC again, then set the other 4 valves. This sure beats rotating over and over for each set of valves. Most of the valve gaps were a little over 0.3 mm which is a good thing. I set them all to the 0.3 mm spec.


End of valve lash adjustment procedure.


Larry

 

[GuglioLS]

After the valve lash adjustment, Now it was time to drain the oil, remove and replace the oil filter. It takes a NAPA Gold 1206 oil filter:

I used Chevron DELO 400, 15W40 Heavy Duty oil for Diesel engines, it took eight quarts:

Then I removed and replaced the Fuel Filter with a Baldwin BF-954:


End of Engine oil, filter and Fuel Filter replacement.

Larry

 

[GuglioLS]

Next up was the cooling system maintenance. I had to crawl under the front of the blade to get to the radiator drain. So I blocked up the blade for safety:



I drained the radiator:

Then the engine block:

I FLUSHED & FLUSHED then flushed some more until the water came out clear. Then I closed off all the drain plugs filled the system with distilled water and added some coolant system flush and ran the Dozer for a half hour. Then I Drained that out and flushed again until the water came out clear again.

After all the flushing I had a pretty big puddle of mud
I then filled up the coolant system with 1 gallon of Fleet charge SCA antifreeze, then one gallon of Distilled water, then added 2 quarts of pre-diluted Fleet charge for a total of 10 quarts of coolant:


End of cooling system maintenance.
Larry

 

[GuglioLS]

By this time I am trashed - I look like a dozer mechanic - black with soot, grease, oil, and mud from head to toe with a hint of diesel.

Now I checked the track tension. Pretty easy just lay a board across the tracks and measure the slack in the middle. To set the tension there is a cylinder that is pumped up with grease, that in turn pushes the track farther apart making it tighter. If you make it to tight, just turn a nut and let some grease out.

Check out that spring:

Tracks tension is set to 30 mm slack on both sides now. All done with that. It was real easy.

Larry

 

[GuglioLS]

On the home stretch. Now it's time to remove the floor plate to check out all the gizmo's underneath. From here I adjusted the clutch pedal free-play, the break pedal free-play, and the Left / Right Steering levers free-play.


And one more adjustment - the Inertia Break band

The clutch on this is a "wet" clutch (submerged in oil) and there are massive gears in the transmission. So there is lots of inertia and fluid coupling between the clutch output shaft and transmission input shaft. When you push in the clutch, the fluid and inertia keep the output shaft turning (a bad thing). To stop the rotation of the output shaft when you push in the clutch, there is a break band around the output shaft called the inertia break. I adjusted the tension on the break band to stop the inertia when you push in the clutch to change gears:

Thats it, I'm done, the Dozer is ready for some action.

Larry

 

[GuglioLS]

One night a while back I returned home from another road trip to El Paso, TX.
It was a long drive so I was sitting on my butt for a while. When I got home I needed something to do so as to move around a little bit.
So this is what I did:
The Armrests on my dozer were falling apart so I made some new ones
Here are what the old ones looked like (Falling apart)

The "T" nuts were all rusted, and the particle board was disintegrating:

Had to use a bolt cutter to get the old bolts & "T" nuts off of the mounting bracket:

Larry

 

[GuglioLS]

Found some plywood scraps and cut them up into little pieces on a table saw:

Glued them together to get the thickness close to the originals:

Then aligned and clamped them together:

Before the glue set, I used a pneumatic Brad gun to tack them together (Brad let me borrow his) No really it's from...... well you guessed it, Harbor Freight. Except I buy the "good" HF tools


Larry

 

[EddieWalker]

Larry,

Congrats on the dozer!! And the video was fun to watch.

I know you already bought the new muffler, but next time, you might want to consider an auto muffler on the tail pipe. The muffler on my dozer sells for over $800 and was rusted through. The metal on it is fairl heavy, so I welded up the holes and the put it back in. I have a 3 inch tail pipe and found an inline muffler for $75 that works great!!!

You know the old saying??

The two happiest days of owning a dozer is the day you buy it and the day you sell it!!! I'm looking forward to my next happy day. hahahaha

Eddie

 

[GuglioLS]

A few of the corners needed to be rounded so they got cut on a scroll saw:

That saw works nice for curves as the blade is very thin and narrow:

Glued:

Then tacked together:


Larry