Anyone know hydraulics/troubleshooting?

[cw_racefan]

Sort of garage related (I'm working on it in my garage)...

I have a mini skid steer (stand on variety) and while cleaning up snow, it started puking hydraulic fluid out the breather vent on the tank. I messed with it a little bit, and it appears that something is causing the fluid to foam. Fluid looks clean, doesn't look like there's any water, just foam. The lift cylinder has a bit of a leak, but has had it for over a year with no issues. No idea where to start troubleshooting, since I've never worked on hydraulics before. Changed the filter, topped off the fluid thinking it might be low, and still the same issue. There does appear to be a small drip from the housing between the gear pump and the engine. It's a Kanga G520 skid steer if that's of any help. Not sure where to start looking?

Thanks!
Craig

 

[TheGrooveking]

You are sucking air into the pump on the inlet side, which is causing the foaming, find the leak and fix it. Also check your inlet screen on your pickup tube in your tank.

TheGrooveking

 

[tyrell2004]

Check the pick up tube into the tank for cracks or loose fittings to pump; could be sucking air intermittently into pump.

 

[Jey]

Pump is cavitating.

bringing in air, or the pump is going south.

Bad. Run it the least as possible as if it's not the pump, it will be failing soon due to not having a full intake.

 

[scopx]

The best source I know is "Brendan Casey". Type his name in search engine. Was able to get on his periodic troubleshooting e-mail list. Can't find link now or would post ref here. He has answers to lot of common fluid problems.

 

[crewchief888]

Sort of garage related (I'm working on it in my garage)...

I have a mini skid steer (stand on variety) and while cleaning up snow, it started puking hydraulic fluid out the breather vent on the tank. I messed with it a little bit, and it appears that something is causing the fluid to foam. Fluid looks clean, doesn't look like there's any water, just foam. The lift cylinder has a bit of a leak, but has had it for over a year with no issues. No idea where to start troubleshooting, since I've never worked on hydraulics before. Changed the filter, topped off the fluid thinking it might be low, and still the same issue. There does appear to be a small drip from the housing between the gear pump and the engine. It's a Kanga G520 skid steer if that's of any help. Not sure where to start looking?

Thanks!
Craig

as stated before, check the suction hose from the tank to the pump, they probably have hose clamps on them, the hose may have "hardened".
if you have an external leak, you may be sucking air from there as well when the engine is shut off.

questions
#1 are the hydraulics jerky or noisy?
#2 is this a hydrostatic drive, or belt/ clutch driven?

 

[scopx]

Just got a periodic email from site that explains in plain english (only way I can understand) some of the principles of hydraulics-and troubleshooting. Its a good read. Hopefully, link will be below.

http://hydraulicsupermarket.com/technical.html

 

[cw_racefan]

Thanks for the suggestions, it'll be this weekend before I can mess with it again.

Crewchief - answers to your questions:

1) Nope, hydraulics are smooth, no jerkiness
2) Hydrostatic. There are two hydraulic motors that drive the front wheels, then the rears are driven by chains off the front.

I'm wondering if the pump itself may be going, since I do have a small drip out of a weep hole on the bottom of the pump coupler. I think that's new with the foaming. I'll check the suction hose/pipe and probably pull the pump and see what it looks like.

 

[JBurgess]

I assume the filter you changed is the return filter. There should also be an inlet stainer, usually wire mesh where the intake comes from the tank. If it is clogged it will cause problems.