742 Hydraulic Fluid Change?

[qtband]

I am currently using Hydraulic Fluid in my 742. If I wanted to change over to motor oil, How would I drain and change?

 

[brdgbldr]

I am currently using Hydraulic Fluid in my 742. If I wanted to change over to motor oil, How would I drain and change?

The chain case oil you need to pump out. You can access this either from the plug in the front of the chain case or you can remove the front access cover on top of the chain case.
The oil that gets pumped through the system is impossible to get completely out unless you remove every line and cylinder. You can get a lot of it out by hooking up a hose to the auxiliary line and pumping it out with the machine. Just stop as soon as it begins to sputter out.
I'm not sure why you would want to use motor oil in your hydraulic system. The chain case is no big deal since it is just an oil bath for the chains and bearings. But hydraulic pumps are very finicky about what goes through them. You can get NAPA AW 46 hydraulic oil for under $50 for 5 gallons and even cheaper when they have a sale, which is most of the time. Bobcat stopped recommending using motor oil in the hydraulic pumps in the 1990's.

 

[Wayne440]

...Bobcat stopped recommending using motor oil in the hydraulic pumps in the 1990's.

My guess is that the fact that Bobcat had started selling their own brand of hydraulic oil had a lot to do with that.

 

[qtband]

The chain case oil you need to pump out. You can access this either from the plug in the front of the chain case or you can remove the front access cover on top of the chain case.
The oil that gets pumped through the system is impossible to get completely out unless you remove every line and cylinder. You can get a lot of it out by hooking up a hose to the auxiliary line and pumping it out with the machine. Just stop as soon as it begins to sputter out.
I'm not sure why you would want to use motor oil in your hydraulic system. The chain case is no big deal since it is just an oil bath for the chains and bearings. But hydraulic pumps are very finicky about what goes through them. You can get NAPA AW 46 hydraulic oil for under $50 for 5 gallons and even cheaper when they have a sale, which is most of the time. Bobcat stopped recommending using motor oil in the hydraulic pumps in the 1990's.

You saved me a lot of work. I'm gonna leave it as is.
Thanks!