Komat'su PC60-7 --Just Purchased Used--Some Questions

[Welder Dave]

With the track loose like that, I wouldn't think it would be hard to remove in one piece. With the track off you could better see what's going on with the idler/track adjuster.

 

[Mark A Weiss]

Yeah, but once I yank that track off, there may be no putting it back on, and if I can't fix my problem, I'll have a useless machine on my hands. I'm saving that last resort for after I get some work done with it.
AMS will sell me a new adjuster for $995 + tax (shipping incl).

 

[skyking1]

Get your work done don't throw the track and then deal with it. The rains are coming get your work done and then bring it somewhere nice to work on.
Just pick the machine up and use bucket turns make sure the track is clear of the ground before you pivot. Don't be in a hurry because you can strip it off on a rock if you're not careful.

 

[Welder Dave]

Finish what you can relatively safely. I don't think I'd be driving in swamps and mud with the track loose like that. If the track came off could really ruin your day.

 

[Mark A Weiss]

Fortunately, I'm done with the swamp work. It's unfortunate that I have this second track that I can't use, and that I stretched out the other track that would otherwise be serviceable, in my attempts to loosen the adjuster. But yeah, my goal is to get some major work done. I think this repair is going to require special equipment that I don't have. That will mean getting outside help.

 

[Welder Dave]

Once the track is off you should be able to get a better idea of what's wrong. I think if you would have had someone experienced look at it in the beginning, it would have been fixed a while ago.

 

[Mark A Weiss]

Once the track is off you should be able to get a better idea of what's wrong. I think if you would have had someone experienced look at it in the beginning, it would have been fixed a while ago.

Where do I find such a person in western CT though? I wish I could just call a local dealer downtown, but there's no Komatsu dealer anywhere near me.

 

[Tags]

Any mobile heavy equipment mechanic would know what to do.

 

[Mark A Weiss]

Any mobile heavy equipment mechanic would know what to do.

When I search on that term, I find a lot of job listings, but no one offering the service in my area. I do find mobile mechanics that will work on cars and trucks. That's about it though.

 

[Welder Dave]

Call the places with the job listings!!! They must have other employee's and they're busy enough to need more.

 

[Mark A Weiss]

It was an interesting day today. First, I drove the excavator to the east side of my property to clear the jungle that started encroaching on the house. I had to make my way between numerous large red oak trees, lots of 90° turns. Made it through all of them without the old loose track falling off. Drove straight ahead in the cleared area and slowly built a path I could drive over by moving lots of rocks and creating a flat enough path so the machine could drive without tipping over. Got to a an area when I drove a little further and heard something go pop under the left (new) track. Got off the machine had a look.. the NEW track had come off the sprocket and idler! And it was tight before I left the back yard. Spent the next hour with a comealong and a grease gun and got the track back on and tightened again. Baffling that the tight track fell off, while the loose and sagging track did not.
While I was returning the comealong to my truck parked on the road, my neighbor, whom I'd met at the marina when I rented a boat two days earlier, noticed I had a track problem and so I mentioned the other track being stuck. He's into heavy machinery and owns a number of large machines himself, so he said to bring the machine over to the barn where he has the tools to deal with this. We'd been neighbors for decades but had never met before, until the boat rental when we had a chance to talk and he complimented me on my excavator. So it looks like I may get the help I need with this, finally. After these three loads of fill come in, I'll take him up on his offer.

 

[A. Williamson]

You get that idler figured out?

 

[Mark A Weiss]

You get that idler figured out?

No, not yet. I've taken some decent pictures from the underside, and there's no broken spring hung on anything. Nothing to indicate a jam. So I'm just periodically shooting oil into the area and using the machine to get work projects done. In September, I'll take up my neighbor's offer to help me fix the machine. I just need to drive it next door to his barn, where he has the tools and equipment to repair heavy machinery.

Meanwhile, enjoy a boring video of my machine spreading fill in the back yard...

 

[Mark A Weiss]

I drove the excavator a short distance to the west side of my property today and again the NEW track, the one that was tight as a banjo string, came off again.
Ironically, the old track that has a Japanese part number and may be as old as the machine itself, which got stretched out from my attempts to loosen the stuck adjuster, never falls off, despite flopping around due to the looseness.
Even more strange was the fact that when I attempted to pump grease into the adjuster after loosening the track to move it back onto the idler, I could not find the Zerk fitting. It's GONE!
I ended up removing the entire assembly with the long bolt, check valve and Zerk fitting from the stuck adjuster and moving it to the working adjuster, so that I could tighten the track again after putting it back on for the second time. What happened to that Zerk is a mystery. I pulled the old part and it's not broken. The female threads are still there. Somehow, the Zerk unscrewed itself and vanished. Baffled!
Five minutes of moving the machine and 2 hours of trying to get that track back on and figure out work around to the missing Zerk.
The new tracks must be more stretchy or have shallower track for the idler, for it seems to easily come off, no matter how tight I make the adjuster.

 

[Mark A Weiss]

Today was a breakthrough. As I'd mentioned, I had to take the Zerk fitting from the stuck adjuster and move that whole plug assembly to the good side because the Zerk had mysteriously vanished (I have a theory that pressure washing may have caused it to unscrew). Anyway, I drove the machine today, just a few feet and the other (stuck side, old track) fell off due to no grease and the adjuster having moved about 1/2" back. Managed to get it to flat enough area, put blocks under it and pulled the front of the track off the idler. Cleaned out the tracks with high pressure water and put a chain through the hole in the idler wheel, attached other end to bucket and was able to slide the assembly out (but I stopped short of having it fall out) and confirmed that the assembly can be replaced.
I thought maybe I could open the grease fitting and use a 6' crowbar to pry between the piston and yoke, but they won't budge. I also tried moving the yoke out of the frame and using crowbar to try and rotate the piston (not sure if a working piston allows rotation) hoping I could break it free. No luck there.
I'm probably going to have to shell out the money for a new assembly. In the meantime, I've shot more penetrating oil into the piston seal area and coated everything with oil.

 

[Mark A Weiss]

By the way, I have a warning light on the console, the one with the grease gun icon. The former owner disabled the automatic greasing system and manually greases the machine. But apparently there must be some timer that expects communication from the (now disconnected) automatic greasing system.
I am wondering how do I reset that?

 

[Mark A Weiss]

Now I really got my self into trouble.
Decided to slide the whole assembly out today. Put it on the back of my truck using bucket and chain. Tried putting a borrowed Zerk fitting on this part with the missing fitting and pumping grease, but the plunger didn't budge at all. I've been flooding this with penetrating oil for the past 3 weeks.

So now it's on my truck. Who in the Danbury CT area works on rebuilding this?

 

[heymccall]

Place spring and ears back in frame and rotate the idler assembly, and rod around and around. That usually breaks any mild friction. Then retry.

 

[Mark A Weiss]

Place spring and ears back in frame and rotate the idler assembly, and rod around and around. That usually breaks any mild friction. Then retry.

Before I removed this assembly today, I stuck a 6' long crowbar in between the yoke and idler and tried to turn the rod to break it free, but it would not budge!

 

[Kobelco ireland]

You will have to get creative with that try what heymccall said but with a bigger pry bar. Also try putting the grease fitting back in and pump as much pressure in to it as you can and at the same time push the idler and spring assembly apart with a jack or a porta power if you don't have a porta power borrow rent or buy one.
Also you might want to repair the top frame rail before you reassemble everything