Hello everyone, I am about to change my chaincase oil in my '99 863 Bobcat. It's a used machine, and I've spoken to the original owner and he never changed the oil, just confirmed the level, which is still good after 1350 hours. The oil itself looked a bit murky, but nothing that unusual I don't think for the situation. Since I've owned it, it's been inside always, so not water issues from me, but I want to change it now. I was originally going to suck it out and pump it the new back in by the same little hole in front, but given that it's never been changed and it will take probably 8-10 quarts (I'm assuming that's wright) of AW 46 (a little pricey), I think I want to open the access cover by your feet and do it right, cleaning it all out etc. My main question is, should I bother replacing the original gasket (foam style) or simply silicone with a good silicone like Permatex Ultra Grey (which seems suitable for the application), or perhaps even a lesser expensive Permatex Black will do? It seems a lot of people just do silicone, but I like to do things by the book. Though, I've read that the new machines don't use the old foam anymore because they leak too easily. New bobcat owners, is that true? So, what method is best? I'm starting to think the silicone will be an improvement over the original foam. But, will not having the form affect anything in terms of taking up the gaps, say where the welded seam is? Thanks in advance. Joe
When I was at the bobcat dealer gaskets were no longer available so silicone is the only option really. We always used black rtv. Just use a little extra were it is welded together
G'day, Owner of Bobcat 753 C series and I expect a very similar beast. I had the same question. Forget original and use Silicone. You will be glad you opened it to get the 'crud' out after so many years no matter the liquid is still at the same level. I was told many methods and in the end the best way was to drop a drum pump into the sump and simply pump to a container. That is the bottom of the drum pump in the bottom of the chain sump. I then soaked up the small remainder with rags and a long screw driver. Inspect the mechanicals while there. Good decision to do it properly in my book! Regards, MX45.
Hi guys, Thanks for the responses, I appreciate it. I figured it would be a good way to go. The original foam looks very greasy around the edges, so I expect it is leaking past a bit, anyway. Yeah, the regular "Black" permatex is a bit less money, and I like the flexibility of using more of a less expensive product than worrying, so I'll probably just go with that. As far as cleaning it out, I am going to go with the "suck bucket" method, with a wet-vac, which I think Willie on here coined. I've used it on some other clean up projects, and it's worked well for me. Now, if I understand correctly, these Bobcat chains do not take any adjustment, right? Aside from the usual wear, are there any tolerances I should be checking or anything else, while I have it open? Thanks. Joe
your machine should have a drain hole in the chaincase. look under the rear of the machine for a rectangular plate. the chaincase and fuel tank drains are under there. rubber grommet and a steel plug. :drinkup
Hi Crewchief, Yeah, I know it has the drain plate and plug. The only thing is Bobcat advises changing out that plug, which I think tends to break or not go back in well, correct me if I'm wrong here. So I figured, I'd just leave that plug alone, and drain it out the top, since I'm cleaning it out anyway. Joe
The plug is usually fine its the grommet that causes problems. If you drain through the plug you can jack up the front and wash everything to the back out the drain hole.
the plug isnt that expensive, and as hiniker88 says, everything will flush out the back.... :drinkup
The suck bucket method works great. The best sealant in my opinion comes in a small aerosol can with a nozzle, I think it's called The Right Stuff, it's at Auto Zone etc by the sealants. It' sets up faster and is much more resistant to oil than silicone.
Well, I went to my local autoparts store yesterday and picked up a tube of Permatex Ultra Black RTV silicone. I think that should be sufficient for the job. Besides, this machine stays indoors, and I'm accustomed to blowing out the cab, rather than washing it, so I don't expect much in the way of water intrusion anyway. Regarding the plug, I guess I could remove it to drain and replace it, but my local Bobcat store is about 45 minutes away, so it's more a matter of not wanting to go to get just that, or wait for it if ordered online. Besides, I don't really know how much easier it would be than the suck bucket method. But, we'll see. If I do decide to get the plug, does anyone know off hand what the part number is for it? I couldn't seem to find it on the Bobcat website. Joe