Equipment Guys - What Size Excavator Do I Need ??

[Dockmaster]

I believe there are quite a few heavy equipment guys on here so I figured a good place to get some input and advice. I have a 5.5 acre property in Central Oregon. It has a lot of rock on it. I want to use the big rock to build a retaining wall then fill in behind it with the small rock. Some of the bigger rocks weigh around 5000 lbs, most are going to be half that or less. The area I want to put a wall will extend out from where the property slopes down. My wall will be a half circle of about 15’ diameter and and a little over 10’ tall. 
My questions are:

1. How big of an excavator do I need to handle rocks up to 5000 lbs? I was thinking to buy a decent condition used machine then sell it when I’m done. I have some experience operating but not a ton. It’s hard to find true lifting capacity specs and I don’t want to push a machine to the limit or only be able to pick up a rock between the tracks. I was thinking something like a Kubota EX80 or maybe even an older Hitachi 120. 

2. Should I go rubber tracks or steel? I have existing dirt road that I would be operating on most of the time. I prefer not to tear up the road any more than necessary. I will need to travel over some uneven ground to pick up some of the rocks. 

3. As I fill in behind retaining wall with rock, do I need to add fill dirt to help fill around the rocks? Once I’m at my grade level I plan to finish the area off with 3/4 - gravel and make a fire pit area. I was thinking if I don’t use dirt as I fill I run the risk of little sink holes as stuff settles between the rock? 
 

Here’s what I’m working with and the area I want to fill in. Basically, where you see the rock slope in second picture, I want to extend that out about 15’ in a half circle. 

 

[John@Outfront]

So the mid size excavator are going to be a premium  I bought a 2004 JCB js220  that’s a 22 metric ton unit   Cost new $250k  purchased it with 9000 hours and needed $10k of work but paid $25k for it  buying units in the 20 ton range seem to be more plentiful and way cheaper  I have move lots of rock and am keeping it around to build a bomb shelter  the mid size may be more your size but I have never seen a cheap one  I can move 10,000 pound rocks. Very relaxing I must say

ps I rented a 225 Deere for $900 a day  it was awesome but would get broke fast so then I purchased the JCB  btw steel tracks are no problem with dirt roads if mostly going straight  I also have 5 acres

 

[cali kid]

I’m a Cat guy always have been always will be. I’ve operated some Volvos, Komatsu, and some Deere all nice but when it comes to ergonomics, cab fitment, and control response I’ve always like Cat the best especially on dozers and graders. I’d say around a 335 with a thumb to pluck rocks. 

 

[Rorschach]

John's right on with 20 ton machines. Pound for pound they're the best value in the used market. I've been working on and around excavators/trackhoes for 25 years and I'm still surprised at their capabilities sometimes. There's times you think the machine you have is too small to do a particular thing and they handle it like nothing. That being said, Mini Xs can do a lot of work for as small as they are but they're pretty expensive for what you get. For what you're doing you're going to want a thumb. Hydraulic thumbs are nice but a welded on static thumb works great too. It's mostly minis that have rubber tracks. Some of the rubber tracks that don't have actual chains in them don't last that long and have to be replaced periodically. Some of the larger rubber tracks that have actual chains inside them with rubber molded on the outside last a long time though. But rubber still wears faster than steel. Stay away from any machine that has any exhaust after treatment, especially pre def stuff. My policy when buying a machine like this for myself is the older the better because an old machine will be cheaper to buy and parts will be cheaper, less electronic crap, you get my drift. If I'm buy a machine like this for myself I'm not looking for high production though. @John@Outfront, your JCB is considered a midsize or "midi".

@Dockmaster A 335 is a pretty big machine. Someplace in the 70-80k lb range. Probably a lot more machine and $$ than what you need.

 

[Dockmaster]

I appreciate the input. I was thinking maybe go a bit bigger since I have to have it hauled regardless. In my area some of the less expensive machines seem to be in the 120-200 range. Good advice on going older and staying away from the electronics. I’m also deciding if I want to get a dump truck or just a dump trailer. I will need to haul from around the property so don’t won’t to have to travel that much with the ex. 

 

[Rorschach]

A machine like that JCB @John@Outfront has is a lot of machine and will do anything you ask it to. It's somewhere in the 40-50k lb range. Just look at the rock he has in the bucket. Check out Ritchie Bros Auction if there's one near you. 

 

[Rorschach]

If you're just going to keep it on your property then you could probably find an old beat up dump truck for about the cost of a dump trailer. My experience with dump trailers is the lifting devices they use are really weak if you load anything heavy in them

 

[John@Outfront]

Pulled out a stump of an oak with 2.5’ foot diameter trunk you can do a lot of cool stuff

 

[GBR]

@Dockmaster I will check with our dealers and see what is available and let you know, the mini's with rubber tracks are good machines but a little small for what your wanting to do a 200 size machine will get it done a lot easier. Pre emissions are way better 90% of our down time with our new excavators is after treatment crap and it's not just excavators all our late model equipment and trucks are driving me crazy keeping them at work. Anyway I will see what I can come up with for you maybe something in the Bend Redmond area.

 

[Dockmaster]

@Dockmaster I will check with our dealers and see what is available and let you know, the mini's with rubber tracks are good machines but a little small for what your wanting to do a 200 size machine will get it done a lot easier. Pre emissions are way better 90% of our down time with our new excavators is after treatment crap and it's not just excavators all our late model equipment and trucks are driving me crazy keeping them at work. Anyway I will see what I can come up with for you maybe something in the Bend Redmond area.

Thanks! I’m not in any hurry. I think anything from around a 100 to a 200 will do the job. I had an old Ford 5550 backhoe for awhile. I could move the rocks but the biggest ones had to be chained to the front bucket and it was pretty overloaded. Still, I wish I hadn’t sold it, it was a good machine.
 

My place is outside of Madras at Lake Billy Chinook so Redmond/Bend is fairly close. Depending on weight of machine and delivery truck they may have to around through Sisters. There are two bridges over the Deschites and Crooked River’s that I believe are 40t max so they may have to avoid those. 

 

[Agricon]

A couple years ago I picked up a JD 790 for 10 grand needed a little work but not much, also picked up a tandem axle dump truck for 2000. both had to leave ca. because of smog. I have 55 acres so i could care less about the emissions. They will never leave the property. in Ca. you have to register your off road equipment, so most companies send there old stuff to auction. A guy came to my shop the other day and was trying to sell a JD 790  for 15000. If you're interested I can try to track him down. We're closed this week but can get it next week.  

 

[Dockmaster]

A couple years ago I picked up a JD 790 for 10 grand needed a little work but not much, also picked up a tandem axle dump truck for 2000. both had to leave ca. because of smog. I have 55 acres so i could care less about the emissions. They will never leave the property. in Ca. you have to register your off road equipment, so most companies send there old stuff to auction. A guy came to my shop the other day and was trying to sell a JD 790  for 15000. If you're interested I can try to track him down. We're closed this week but can get it next week.  

When I google John Deere 790 it comes up as a tractor. I think an excavator is better for what I need. Also, trucking from CA to OR may be cost prohibitive.