Replacing Hydraulic Hose Help

[14aman]

I have a hydrualically operated snow blade on my B2620 tractor.
After pinching and bursting the hose that lowers the blade, I purchased a new hose and some Super UDT fluid from my kubota dealer.
I replaced the hose; added fluid and then attempted to bleed the system by leaving one end of the new hose disconnected and moving the blade until only straight fluid (no air) came out.
I then connected the loose end and operated the blade.
It turns left and right okay; goes up okay; but, while the blade does go down, it does not have nearly the power/strength in the down direction it had before the hose bursting. It used to be able to lift the front end of the tractor - not now. Did I do something wrong or miss part of the bleeding process? Did I connect the new hose wrong?

 

[Swamper]

Welcome to OTT.
You don't usually need to bleed a two way hydraulic circuit after you change a hose. If you cycle the cylinder each way several times any air will be purged out to the reservoir. Then check the oil level and add if needed. If you took the old hose off and put the new one in its place, I don't know how you could do it wrong.
As for the lack of power, I can't think of a reason changing the hose would cause a change in power. The lifting power would be determined by the pump output pressure and the pressure relief valve setting. Maybe someone else has an idea. Larry

 

[Bulldog]

They didn't give you a smaller diameter line did they?

 

[pat331]

My guess is that you still have some air trapped in the line that extends the cylinder. Try to get the front end of the tractor up so that you can extend the cylinder fully. Then operate it a dozen times or more. I'm betting you get all the air out and it will operate as before. Let us know what happens. Good Luck!

 

[Rotel1974]

The best way to find out what you have going on is to tee into the line at both ends of the cylinder and check the pressure with a gauge. If it is in spec you may have a hose with a bad liner stopping the flow to the cylinder. If you have low pressure part of the hose that you took off may be in the relief valve.