looking for used excavators

[ktm250rider]

Im an engineer/homeowner looking to buy an excavator to get some work done around the house. Mainly, build a MX track and clear some fields. Looking around 26K lb. No specific model, just one with a thumb and decent condition. Ive looked at a bunch and getting better at checking things out.
Ive seen all conditions with some needing new pins, rollers, sprockets good and bad and some with leaking pistons. The one thing I cant figure out, is when the main boom is lifted all the way up, the weight seems to rock the whole upper assembly. Is this normal or does it indicate a worn main swivel gear? I tried to see if the assembly would move just by pushing the bucket on the ground but i couldnt detect any play.

 

[Silveroddo]

Sounds like it would be the bearing in the swing circle, heard of them going bad but have never seem it. I know on older machines its pretty common for the seal on the outside of the swing circle to go and given the ammount of work and $$ to replace I know most guys let it go. Just a thoughts.
If you get to a point you have a machine you like get a mechanic to check it out, may cost you a few hundred bucks but can save you thousands.
We had a hitachi EX60 URG checked out one time we were looking at long distance and boy was that the best $250 we ever spent! The guy was importing them from Japan or where ever painting them and selling them with lots of problems over looked. Buyer Beware

 

[ktm250rider]

yeah thats what i was thinking, the main bearing. Its weird that I could not detect any movement of the upper assembly when pushing with the bucket. I could lift the whole tractor up without any noticable movement.

 

[joispoi]

Some of the movement is most likely from the foot pin bushing on the boom being worn as well as the boom cylinder bushings. When the boom rocks, it can move the whole machine. Make sure the tracks are on flat, level ground when you're checking out a machine. If the slew bearing is bad, walk away from the machine and never look back. It could cost you as much as you paid for the machine to have it replaced.

 

[ktm250rider]

There was some slight play in the boom bushing, and on the boom cylinder bushing. The boom bushing was hardly noticable, maybe 0.5mm while the boom cylinder was 1-2 mm of movement. Not a whole lot if you ask me. Again, this was seen with the bucket on the ground and lifting the machine very slowly. Once that play was taken up, the tracks would start to lift off the ground.
Flat ground, Im thinking that may have been more of my issue.
Well, I just found a listing for a CAT 315 thats in my price range so I guess I have another machine to look at. No hydraulic thumb, just mechanical but that will do.

 

[a.paul]

did you see that today (7/27) nh craigslist has an 87 Cat (something...hard to tell from pix but it's a medium/big machine) with a thumb.

 

[ktm250rider]

Yeah, thanks. That one has been for sale for quite awhile, Cat 235. The previous pictures were taken in the winter. I havent gone to look at it but was thinking about since its right in town. I think its too large for what Im looking for. Id like to stay in the <30K lbs as those seem to be selling pretty well.

 

[a.paul]

southworth is bringing me in an 05 311 to peer at in the next few days. with a hydraulic thumb.