Hello Friends, After many years (and help from forum members) stuck engine, broken spring and track tensioner, leaking boom cylinder....... , we are about to start digging some dirt. First off, a big thank you to Ken in NY and other forum members that have checked in and offered help over the years. Looking back, I was offered the excavator at scrap value and really didn't consider how far away it was from running again. This forum is one big reason that this old heavy metal is just about to play in the dirt again. It is an old machine, 2DL01890 an actual 320 with no B, C,D... after the number. The cylinder we just had rebuilt had a fair amount of interior rust. The hydraulic fluid is milky. I am thinking that it would be best to change the filters and put in inexpensive hydraulic fluid as a flush. Then run it for 50-100 hours and change it again. Does this sound like good practice? What hydraulic oil would you use as the first flush and what would you use as the permanent oil? Is there a separate reservoir for the swing? What oil goes there? Is there a site where I can look up the oils and filters for this machine? I have misplaced a service CD I had for this machine. Where can I get another one? All my best, Nolan Scheid
The problem with flushing is that just draining and refilling will get maybe half of the fluid. So, you'll get rid of half of the old stuff, then dump the cheap stuff and you'll have half new fluid, quarter cheap fluid, quarter original fluid. In my mind, for something this age and life expectancy, it's easier to change filters and go. Or dry the fluid and bypass filter it. If you're going to change the fluid, get it clean and dry FIRST, then change half with a better oil.
Thank you Delmer. Is there a place I can look up the filter numbers and which hydraulic oil I need? The machine is pretty low on hydraulic fluid now. If I can get the filters today before going out to the machine, I might be digging dirt by this weekend!! (insert happy dancing emoji with a shovel) All my best, Nolan
You can get an Operation & Maintenance Manual SEBU6656 as a download from Cat Publications for $49. That would be a good investment. Or get a free 30-day trial of scribd.com. There is a pdf copy of SEBU6656 on that site that you could download. Hydraulic system filters are 4I-3948 (spin-on), 094-4412 (return filter inside tank), & 7Y-4748 (suction screen). The suction screen should be washed every 500 hours and replaced every 2000 hours according to the book. Hydraulic oil is a good-quality SAE10W or ISO32 hydraulic oil. Tank capacity about 28 gallons give or take. (The complete hydraulic system is +/- 51 gallons)
Thank you for the replies. I just got back from the local dealer. A freshly printed service manual SENR6045 is $785.53 I decided to pass. I wonder if there is a scribed copy of that one as well. I will use the part numbers to go get another set of filters. Is there a separate oil system for the house rotation? This video has a much newer machine and mentions a swing oil dip stick at 1:08. . As usual, I will have a new set of eyes when I drive out to the machine and look for more details. I hope everyone has a great weekend. Nolan
There should be a dipstick on the swing drive box.
Thank you. I see from the drawing that there is a drain and refill spot. That looks like another thing to put on the list. I will download the maintenance manual and keep looking for the full service manual. All my best, Nolan