Air Bubbles in Hydraulics

capekubota

New member
Jan 11, 2017
62
0
0
canada
I just replaced the seals in the 3 PNT hitch cylinder in my b6200d, due to it leaking down. The new seals fixed that issue, but now when I am using the hydraulics, I am getting air bubbles in the fluid and just today it started overflowing fluid through the breather. It was white with bubbles but if you rubbed the bubbles the fluid cleared ( ie. no water).
When I replaced the cylinder seals, I did not replace the seals on the cap. Could this be sucking air in? Should I have filled the cylinder with fluid when I changed the piston seal, before buttoning it up?
Is there a way of detecting air leaks?
 

JerryMT

Active member

Equipment
Kubota M4500, NH TD95D,Ford 4610
Jun 17, 2017
528
156
43
The Palouse - North Idaho
I just replaced the seals in the 3 PNT hitch cylinder in my b6200d, due to it leaking down. The new seals fixed that issue, but now when I am using the hydraulics, I am getting air bubbles in the fluid and just today it started overflowing fluid through the breather. It was white with bubbles but if you rubbed the bubbles the fluid cleared ( ie. no water).
When I replaced the cylinder seals, I did not replace the seals on the cap. Could this be sucking air in? Should I have filled the cylinder with fluid when I changed the piston seal, before buttoning it up?
Is there a way of detecting air leaks?
It maybe that you pump suction tube/line is leaking air and aerating the fluid. The hydraulic reservoir should be vented so the seals on the cap are to prevent dirt entering the system and not prevent air entry. Is the fluid level correct? Are you using the correct hydraulic fluid?
 

capekubota

New member
Jan 11, 2017
62
0
0
canada
I just checked the fluid and it appears it is at the correct level and after 5 hrs, it’s clear, no bubbles. Actually hard to read on dipstick.

I just changed the fluid a few months ago and used the super tech universal tractor fluid seen here:
https://www.walmart.ca/en/ip/tune-it-universal-tractor-fluid/6000111966712

Just thinkin, if the fluid is still at level now, and that’s after spilling out of the vent, maybe it was over full.?
 

JerryMT

Active member

Equipment
Kubota M4500, NH TD95D,Ford 4610
Jun 17, 2017
528
156
43
The Palouse - North Idaho
I just checked the fluid and it appears it is at the correct level and after 5 hrs, it***8217;s clear, no bubbles. Actually hard to read on dipstick.

I just changed the fluid a few months ago and used the super tech universal tractor fluid seen here:
https://www.walmart.ca/en/ip/tune-it-universal-tractor-fluid/6000111966712

Just thinkin, if the fluid is still at level now, and that***8217;s after spilling out of the vent, maybe it was over full.?
That's a possibility. Does that fluid meet Kubota specs?