How to bleed my hydraulic system on a 1990 473 bobcat

The Bobcat 863 is a skid steer loader model manufactured by Bobcat Company, a renowned manufacturer of construction equipment. The 863 model was produced from 1996 to 2003 and was part of the C-Series lineup. Here are some key details about the Bobcat 863:

1. Engine: The Bobcat 863 is powered by a diesel engine. The 863 was initially equipped with a Deutz BF4M1011F engine, which is a four-cylinder, turbocharged engine. Later models may have variations in engine specifications.
2. Operating Capacity: The operating capacity of the Bobcat 863 depends on the specific configuration and attachments used. However, it typically falls within the range of approximately 1,500 to 2,000 pounds (680 to 907 kilograms).
3. Hydraulic System: The 863 features a hydraulic system that powers the loader arms and attachments. It has auxiliary hydraulic ports for connecting various hydraulic-powered attachments, such as buckets, forks, grapples, and hydraulic hammers.
4. Controls: The 863 is equipped with joystick controls that allow the operator to maneuver the machine with precision. These controls enable the operator to manipulate the loader arms, drive functions, and auxiliary hydraulics.
5. Attachments: The Bobcat 863 is compatible with a wide range of attachments, making it versatile for various applications. Common attachments include buckets for general-purpose loading, forks for material handling, augers for digging, and sweepers for cleaning.
6. Safety Features: Like all Bobcat equipment, the 863 is designed with safety in mind. It features safety interlock systems to prevent accidental operation and rollover protection structures (ROPS) to protect the operator in the event of a tip-over.
7. Maintenance: Regular maintenance is essential to keep the Bobcat 863 operating efficiently. This includes routine checks of fluid levels, engine oil, hydraulic system, filters, and tire pressure.

the hydraulic temperature sender is typically located near the hydraulic oil cooler or the hydraulic tank. It may be mounted on the side of the oil cooler or tank, or it may be mounted on a hose leading to or from the cooler or tank.

Check out the filters,and is the proper weight oil for the hydraulic been changed lately and refilled with correct oil. May have air in the line as well, bleed the line

I don't know Bobcat systems like I do Toyota skidsteer, but on Toyota if the center foot pedal is pressed with no attachment connected, it will kill everything. Could that be happening to yours? Check into friction between your actuators for the attachment fluid drive.

if the hydraulic oil is from the auger head then the machine will fill and bleed out the air
the hydraulic oil would have been in the hydraulic motor that drives the auger

Hi Joseph:
Usually hydraulic components will "self clear" any air in the system just by trying to cycle through the functions a few times.
Have to ask the question............
Did you remove and replace the hoses one at a time, or did you take them all off at the same time?
The reason I ask is............ Could there be a remote possibility that any of the hose onnection locations were switched?

You should use hydraulic oil, not diesel, drain it, refill it and if necessary bleed all the air from the system (some are self bleeding) Dependant on the type of hydraulic system you may have damaged the seals by using diesel oil, that, unfortunately is expensive.

That's one of the first things that came to mind as I was reading through your post; that the system was air-bound. Are there bleeder valves on the system?

In any event here is a website where you can buy the service manual for your skidsteer; https://mypowermanual.com/shop/bobcat/bobcat-641-642-643-skid-steer-loader-service-manual-download-6566135-10-86/

Most hydraulics will self bleed by using them. For some cylinders you can position them so that one inlet will be at physically at the top, actuate that set so that it fills the cylinder on the upper end, let it settle for a few seconds to allow air to move to the top, then actuate it the other way, pushing the oil and air out the top. Reverse the cylinder position so that other end is at top and do it again, fill cylinder from top and allow air to rise then actuate it to push air and oil out again. Repeat several times.

I know you can't get all cylinders to a vertical position so that you have a true top and bottom but the idea is to get one cylinder inlet up while the other is down and the reverse the position.

Other portions of the hydraulic system should bleed all air out of the as you use it or will have bleed ports that allow small amounts of air out and you shut them when oil comes out, such as brake and clutch systems.

If you continue to get lots of air in the system you have a leak on the suction line from the tank to pump.

Ask here, they will find every Bobcat manual or schematics.