Hey Guys, I am going to look at a new for me but used 6 tonne mini ex this weekend to buy. IT has rubber tracks. Can anyone give me a good list on things to check over? I am not really that familiar on how to check undercarriage ( things like track tensioners etc) or how to see turntable wear etc? Thanks for any and all help.
This post from AtlasRob pretty much sums it up. Hope it helps ya.
How do you check a turntable for wear?
Big builder. Lift bucket off ground a few inches, then get out or have someone push bucket from side to side and observe total rotational movement. A few inches is OK, Much more than a foot or so is too much, taking in consideration some slop in bucket pins and boom. You can also use the swing control to turn back and forth and both observe the rotation and feel the slack in the gears. Have someone use the boom to move the house up and down and watch the movement in the swing bearing. Some manufacturers have a spec for this. There should not be much movement up and down in the bearing. I've seen some that were really worn, but they still worked fine.
Kepp the bucket off the ground again. Move it up and down and side to side. A little movement side to side is okay. You do NOT want too much movement up and down.
Special tool. I am a little confused. With the bucket off the ground do I move it up and down by touching the bucket to the ground and lifting or prying with something???? I am guessing while doing this someone is under the cab looking at the bearing at the same time right? Any other expensive areas to check on a machine?
It may pay to get a pre purchase inspection by someone who knows these types of machines. This may cost ~$100 but if you are talking a machine worth $$$$$'s it could be the best 100 bucks you spend on that machine. The inspector will be able to advise you on how much money needs spending now and how much down the track. Plus you'll learn stuff so next time you'll be able to give a machine a quick inspection and figure out if it is worth going further with it. That way you got an independent view point to use in haggling with the seller. Is there any service history with the machine? Used ex Japan machines are notorious for lack of service, always try and buy a locally delivered machine run by an owner/operator. Ideally you would want compression test on the engine and a hyd pressure test but that is bigger bucks and generally only done on the bigger class of machines.
No Extend the stick all the way ouy - this gives you a lot of leverage against the carraige...heck, you might even be able to lift the boom side of the tracks off the ground on a small machine. Grab the bucket with your hands and move it up and down. Helps to have someone else close to the bearing to check it out, yes.
A hundred bucks for an inspection. I won't even start the truck for less than $300. I know I am as good or better than the field mechanics at any of the dealers. Why would I charge less than what they make. A simple inspection on an excavator takes at least 45 minutes plus travel and mileage each way. Add in a written report with all the proper legal language in case the client has a shyster lawyer and you add a couple of hours to the process. Start doing pressures, cycle times precise measurements of undercarriage and wear in implements and the circle and a thousand bucks isn't excessive. I always compare that to the cost of one component failure and usually don't have much problem getting paid for my time.
Big Builder. Just set the boom and bucket at a normal attitude, stick straight up and down, bucket on ground. Either you or someone else has to observe, and the other person just has to move the machine up and down a bit, just enough to take any slack out of the rotek. Rotate the machine and do this every 90 degrees. So far as checking the swing; boom and stick in same position as above, with bucket off the ground a couple of feet or so. Do not engage the swing lock or hydraulic disconnect. You can do this one by yourself. Get out and go out to the bucket and push it back and forth sideways. It will spring back a bit, be careful. Loader/Backhoe boom swing can be checked this way too. This machine will have more slop in swing gear than an excavator.
Thank you. I am going to look at it in a couple of hours. I am looking at two over the next couple of days so I will emply the test you guys have described for me. I think I have a pretty good understanding of it now. I will reply with what I learn today. Thanks again.
so I went out to check this old machine. It was an old kubota 191...about an 89. Swing gear and bearing seems ok. But it has many other issues. Almost all pins and bushings are out of it. House spins much faster one way than the other and stops abruptly ? Any ideas? Undercarriage is right out of it. It would need sprockets, chains, pads and I'm other parts too. Leaks fuel out aound lines into injector pump. This is probally not a big deal. It stared right up after sitting for 6 months though. I figure it would need $ 10 000.00 in parts to fix and quite a bit of time....is this a fair estimate? I am going to look at another newer machine next week. Thanks for listening.
Safety Warning Word of safety here - never have someone underneath a machine while it is being operated. It would also be beneficial for you to take a few pictures of the items discussed on the machines you are looking at and post them here.
I was only looking form outside the track area.