Bleeding hydraulics

grob

New member

Equipment
B7100 L210 Woods mower deck
Sep 7, 2017
2
0
0
Westchester, PA
Hi Guys,
New to this site. Recently acquired a B7100 with loader and backhoe. I have had most of the loader cylinders resealed. The loader is working but it lacks zip....mainly speed. For example, when jacking up the front to use the backhoe, it is almost like you need to coax it to elevate the front. I know that you can "bleed" the hydraulics on a John Deere by putting all the cylinders into full extension simultaneously. Any similar tricks with Kubota?
Thx
GBR
 

85Hokie

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Staff member
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BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
Jul 13, 2013
10,342
2,166
113
Bedford - VA
Hi Guys,
New to this site. Recently acquired a B7100 with loader and backhoe. I have had most of the loader cylinders resealed. The loader is working but it lacks zip....mainly speed. For example, when jacking up the front to use the backhoe, it is almost like you need to coax it to elevate the front. I know that you can "bleed" the hydraulics on a John Deere by putting all the cylinders into full extension simultaneously. Any similar tricks with Kubota?
Thx
GBR
If air is in the line(s) - it will work itself out, may take a little time, I would run all cylinders up/down back/forth dozens of times......

now, you could have low oil? Filter clogged? Screen clogged?
 

grob

New member

Equipment
B7100 L210 Woods mower deck
Sep 7, 2017
2
0
0
Westchester, PA
Thanks for that suggestion 85- I will try that. All filters and levels are recently maintained. Hope it's air in the line.
 

RCW

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BX2360, FEL, MMM, BX2750D snowblower. 1953 Minneapolis Moline ZAU
Apr 28, 2013
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Chenango County, NY
Do you have sufficient RPM?

RPM's are your friend when running the hydraulics. Half - 3/4 throttle or so.

Just another thought.

Good luck!
 
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whitetiger

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Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
Nov 20, 2011
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Kansas City, KS
If you cycle the lift and bucket cylinder a couple times, all air is gone. Your hydraulic suction screen is restricted. You need to drain the oil, plug is on Right rear corner of axle housing. The screen is on the thin bolt head at the rear of the suction pipe on Right side, just ahead of rear axle. Unscrew the 26mm thin hex head, when it is unscrewed you can pull it and the screen out of the tube.

Wash to screen out in solvent, blow it dry. Then hold it up to a light sideways and see if you can see light thru the screen. If you can not see light thru it, throw it away and get a new one. Most of the original screens were actually two layers of screen with filter media in between them. Those can not be cleaned once they get plugged or restricted. If you can see light thru it you have the later screen.

Reinstall the screen thru to suction tube while making sure the two o-rings on the tube are in place. Screw it back into place, snug it up and put oil back in tractor. Start the engine, let it idle for a minute, then rev it up and operate you loader.
 
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ABS

New member

Equipment
B7100
Nov 21, 2022
2
1
3
Brisbane, Australia
If you cycle the lift and bucket cylinder a couple times, all air is gone. Your hydraulic suction screen is restricted. You need to drain the oil, plug is on Right rear corner of axle housing. The screen is on the thin bolt head at the rear of the suction pipe on Right side, just ahead of rear axle. Unscrew the 26mm thin hex head, when it is unscrewed you can pull it and the screen out of the tube.

Wash to screen out in solvent, blow it dry. Then hold it up to a light sideways and see if you can see light thru the screen. If you can not see light thru it, throw it away and get a new one. Most of the original screens were actually two layers of screen with filter media in between them. Those can not be cleaned once they get plugged or restricted. If you can see light thru it you have the later screen.

Reinstall the screen thru to suction tube while making sure the two o-rings on the tube are in place. Screw it back into place, snug it up and put oil back in tractor. Start the engine, let it idle for a minute, then rev it up and operate you loader.
I believe I may have found the answer to my issue, I cannot see threw my screen filter no matter how much I clean it. Looks like I have the original screens thus I have very little forward and reverse. Going to drop the oil, remove and replace the screens. Good comments and well done to calling this out.
 

DustyRusty

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Equipment
2020 BX23S, BX2822 Snowblower, Curtis Deluxe Cab,
Nov 8, 2015
5,164
3,832
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North East CT
Have you changed the hydraulic oil on the unit? If the screen is clogged, the oil that is in it presently might be the culprit to the clogged screen. I would check with the Kubota dealer to see if the Kubota Super UDT2 might be a better oil to use in your tractor. I know that it is expensive, but think about how long it will last. Sometimes the most expensive oil turns out to be the least expensive due to its longevity of use.