I don't really understand the layout of the chain case. S250, though I'd imagine the S machines are all similar The service manual I have is complete **** and just tells how to check and fill the oil, that's it. When I bought the machine the chain case was close to empty. I know its in the very middle of the machine and runs from front to back. How do the two drive motors run the wheels? I know there is a chain the links the 2 wheels, but does the drive motor have a sprocket that runs on the chain? Other than axle shaft seals near the wheel? How else could oil leak out?
Yes the motors have sprockets to turn the chains. Oil could leak through wheel seals or motor seals.
Generally the drive motor has 2 sprockets each with a separate chain. One chain goes from one motor sprocket to the front wheel, the other one from the other motor sprocket to the rear wheel. Something like this. Losing oil out of the chaincase usually means via the wheel seals, unless the chaincase has an inspection cover on it that is normally below the level of the oil, in which case a dodgy gasket can cause oil to leak from that location.
No leaks from wheel seals that I can tell. I'm not sure how bad it was to not have oil... Or how long it was like that. I had filled it and drained it after running it a bit and the oil looked ok. That photo is a bit different setup than my machine. There is just 1 chain case in the middle of the machine which runs both sides. It has a fill plug in the front and a drain underneath. I have no idea how one would get to the chains even? I wish the service & maintenance manual I had had anything like that so I could have an idea. It should be just called an owners manual.
On a bobcat its a total pain to work on the chaincase, one of the worst things about those machines in my opinion, along with a pretty long list of others as well, on bobcats the motors are on the outsides of the case and the gears are on the inside of the drives, most makes have it the other way around, or two separate chain cases. As for how the oil got out, if you just bought the machine, I'd venture a guess someone never put enough back in after an oil change, just watch the level over the next few weeks and if it doesn't change any, don't worry about it, you'd notice a wheel seal leaking pretty quickly if its leaking very badly at all, there will be a puddle under the machine after sitting for a while. When you drained it if the oil looked fine, just fill to the proper level and run it would be my advice, how things have been done to it in the past are too late to worry about anyhow at this point, as for working on the chain case later on if need be, there are a few guys on here that can help you out with that, but it'll be a job you'll never forget that I can assure you. If there was no metal filings that came out when you drained the oil, I would get too shook up over it, but while on the subject, just how much oil did you put back in, how high is the oil in the chain case, most don't take much, a few inches of oil is all that's needed on most makes and models.
It took about 5 gals from what I remember. I bought the machine this spring and did a complete service on it then. I was just thinking about it that I hadn't checked the level in a while. The service manual said to fill with hydro oil to the plug level. Seemed like a ton of oil!
Its been too many years since I owned a bobcat machine but none of the skid steers I've ever owned had that much oil in the chain case, most just use a few inches is all. Some of the older gehl's used the chain case as a hydraulic tank as well, but that was a long time ago and even they quit doing that the last time I looked. I'd double check the quantity it requires before I'd get too shook up, by the way how much came out of it when you first drained it?
I'd suggest putting something heavier than hydro oil in it, even if it's just engine oil. For your climate an 80W/90 EP oil would likely be a tad too heavy.
i use ISO AW 32/46/68 multi grade hydraulic oil in all my machines hydraulic systems, and in the Mustang's chaincase. Works well in hot and cold weather.
I looked up the info to see... "The chaincase contains the final drive sprockets and chains and uses the same type of oil as the hydraulic/ hydrostatic system" Chaincase reservoir capacity 41.6 l That works to almost 11 gallons. Maybe I did put 2 pails in the thing, it's been a while since I did it. I don't really understand why the chains are in oil anyhow? Lots of stuff uses chain dry in open air, no lube.
Bobcats generally use chain case oil to lube the wheel bearings also, other brands have grease zerks.
It uses hydraulic so you can't tell if one system is leaking into another one. I take your point about dry chains, but try to think of an example where a chain is transmitting the level of torque that these ones transmit that runs dry. My motorcycle uses a "dry" rear chain as well but guess what - the chain is lubricated when it's assembled and every separate joint is sealed with a O-Ring at each end of the pin to keep the lube where it's supposed to be, inside the chain.
I remember when I had to take the chain off my motorcycle and soak it in oil overnight. I think it was like every 800 miles or so. That's going back in time some.
You've never used Linklyfe chain lube then I take it ..? TBH I Don't miss the stuff one bit, but that was before we had O-Ring chain. http://www.aircooledrdclub.com/smf/index.php?topic=27132.0
Nope. Don't recall that product being around in the mid-'50's. Had a bad bike wreck in '57. Broke back in three places. Started riding again fifteen years ago, shaft drive.
Oils cheap compared the cost of the chain, sprockets and drive motors.
I was thinking that too.....
Some say 10w30 SAE oil others say 10w40 . Others 15w40 diesel grade. Go figure. Then others say hydrolic. Man, this is confusing to read all the differences recommended by others.
4 year old post, any updates from the OP?
Update to post for people searching. In my bobcat I put all new chains from dealer, all new wheel bearings and gear reduction box bearings and I used 10w40 motor oil in chain case as per manual. In hydro system I use aw32 or aw46 as per dealer recommendation. Nothing special about the oil, just plain old $20 a case motor oil.
I didn't remember being on here before. Was googling what goes in there as I couldn't remember. Must still have the aw32 from 2013 in it as I've not touched it other than I vaguely remember checking the fluid level in the last couple years. Have put probably 2000 hours on it, mostly moving logs. Started keeping better track of maintenance with a spreadsheet a year or so ago. With probably about 20 pieces of equipment and trucks, i couldn't remember well enough anymore. Hydraulic oil is what Bobcat specs. Supposed to change it every 1000hrs, which to me seems excessive considering there's alot of oil.
Also Bobcat specs their hydraulic oil which is an iso 46, but also can use engine oil. 10w30 for above 0* and 5w30 for below. I can only guess it's not too fussy if anything from an iso 22 to iso 100 will work. I know in winter it's not overly happy moving the auxiliary, the grapple, till I get a bit of heat in it.
I just did a major service to my 2004 S300. I like to use Bobcat PG purple coolant, and Bobcat hydraulic oil. Not sure why, but I do. For the chaincase I used 13.5 gals of Traveller 15W40 diesel oil from Tractor Supply. I now live in mid south Tennessee and I figured that would work well. I only have 1830 hours on it, and I am the original owner.
Funny enough, I was google searching how much this held for oil and this thread came up from me when I was first working on it. Was doing some work on it yesterday and after cleaning out the 2 front footwells through the access plates, figured I should check the chaincase oil as I couldn't remember when I had done that last. Level was ok maybe slightly overfull, but looked like old gas engine oil. Brown gross looking. Was near clear hydraulic oil that I put in. Fought with the plate to get to the bottom drain plug, the bolt heads were all worn down from rubbing on the ground. Got the rubber plug out. Course its coming apart and I don't have a spare. BUT there was a good quart of water in the bottom! I'm going to pull the front plate and reseal that just in case, not sure where else it would be coming from. There's 3 plates on the top from what the parts book shows, but I've never touched the back 2, don't imagine they'd be leaking. There's a breather on the middle one, I guess maybe could be getting in that? Machine is generally outside.
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