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How to bleed my hydraulic system on a 1990 473 bobcat

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It bleeds itself, only if a ram has been disassembled you need to extend and retract the ram several times slowly without building up pressure. then you should be good to go

Posted on Oct 23, 2019


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Posted on Jan 02, 2017


tuyen bui

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SOURCE: how to air bleeding in break system by step by

you need two persons
open the bleeder screw on the wheel that is furthest from the master cylinder and do the nearest last.
have a person pump on the brake pedal and hold firm while you open the screw, then close it before tell the person pump again
repeat until you see no more air come out
make sure you fill up the master cylinder, do not let it run out of fluid

Posted on Feb 26, 2010


Grant Shaw

  • 493 Answers

SOURCE: hydraulic breaking system

My way is to start furthest from the master cylinder & work to the closest. Make sure the master cylinder remains toped up throughout the procedure. With any luck with the lid off the master you can gravity bleed it, ie: just crack the bleed nipple & fluid should start comeing out. Let the fluid bleed a little then tighten the nipple. Repeat for all for. If it will not gravity bleed let me know & i'll give you another procedure. Gravity is best though

Posted on Jun 21, 2012

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1 Answer

Need hydraulic schematics for Bobcat 642b. Any help would be really appreciate

Try requesting the hydraulic system diagrams directly from Bobcat.

Feb 12, 2018 | Miscellaneous

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I took my bobcat post hole auger apart to service it and had to drain the hydraulic fluid! Now do I have to fill the auger head before connecting it to the machine? Or can the machine do it self?

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

Jan 07, 2017 | Cars & Trucks

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How do you bleed the hydraulics on a Bobcat 751 skid steer loader?

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?

Sep 23, 2015 | Toys

1 Answer

I added diesel to the hydraulic tank in my bobcat and never an it. I drained the tank, refilled it, and now the hydraulic system wont work.

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.

Mar 05, 2015 | Bobcat 773

1 Answer

Bobcat 641 skidsteer hydraulic problems.

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;

Feb 20, 2015 | Bobcat Garden

1 Answer

On my bobcat 743 how can i bleed air from my hydraulics

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.

Aug 27, 2012 | RTO Construction Bobcat by Woody Click

1 Answer

My clutch is not angaging need to see how can i bleed

Hydraulic Clutch System BLEEDING The clutch system can be bled using a pressure bleeder. Follow the instructions that come with the pressure bleeder for the proper pressure bleeding procedure. The maximum line pressure while pressure bleeding must not exceed 36 psi (248 kPa). NOTE: To bleed a clutch manually requires the assistance of a second person, a section of hose that is compatible with brake fluid (preferably clear) and fits the slave cylinder bleed screw snugly and a container to catch the fluid that is bled through the system. As brake hydraulic fluid easily absorbs moisture, always use fresh fluid when bleeding a hydraulic system.
  1. Before servicing the vehicle, refer to the precautions in the beginning of this section.
  2. To bleed the system perform the following:
    1. Top off the hydraulic fluid reservoir using a fluid that meets the standards of the vehicle's hydraulic system.
    2. Open the clutch slave cylinder bleed screw and press the clutch pedal to the floor and hold the pedal down.
    3. Close the clutch slave cylinder bleed screw.
    4. Release the clutch pedal.
    5. Check the hydraulic fluid level and top off as necessary.
  3. Repeat the above steps until the discharged fluid is clean and no air bubbles appear during the bleeding process.
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Aug 03, 2010 | 1998 Audi A4

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