I'm new to the digger scene, I recently bought a 2nd hand ex40 that looks fairly tidy. Doing some research about maintenance on the net I found that the price of a final drive freaks people out and its important to change oil regular. Drained the oil from the final drives, black with a slightly burnt odor - firstly I've never seen black oil come from a gearbox before how come this happens? I filled it back up with oil, spun the track a bit, drained again to flush and filled again. The oil that I drained the second time seemed whipped up with bubbles. Is that common - never seen it before? Not sure if I'm using the right oil. I'm using 80W 90 car gear oil. And thirdly... after emptying drain containers I noticed small but noticeable silvery looking shimmery things in the bottom of the container. They are small - maybe 1/4mm or smaller. Do I sell it quick? I was thinking about doing another flush after a few more hours work. Any thoughts? Thx in advance
Doing those flushes is always a good idea. Personally I have never dropped the oil out of any unfiltered gear case and didn't find a little bit of filings. It's good motivation for changing the oil out frequently, and investing in magnetic drain plugs. It will likely be fine for years, just change that oil often, especially when working in the wet/mud Good luck Ken
Gear sets seem to make a little bit of metal all the time. Yes, magnetic plugs and keeping the oil changed will make it last for years.
I would like to purchase magnetic plugs for my finials, where's a good place to get them? Thanks.
Black oil that smells burnt sounds like its been in too long. To get it back to pristine condition you're probably going to have to drain and flush quite a few times. So long as you're not going to work the machine the thinner the oil you use for flushing the better. Engine oil or maybe even hydraulic oil (doesn't have to be expensive you're going to throw it away anyway) would work better than gear oil as a flushing agent. Next time you think about draining, do it either just after the machine's been working for a while or at least raise one track off the ground and spin it for a couple of minutes to warm the oil in the final drive before you pull the plug. I'm amazed that the drain plugs aren't magnetic as standard. Regarding the frothing of the oil - instead of EP 80W/90, try an SAE50 TO-4 oil.