To Bleed or Not To Bleed ???

[crash325]

I am about to replace a 9 foot hydrolic hose that goes to the back hoe.

Should I just let the air in the line work its self out???
Or should I bleed it??? My thinking leave the fitting a little loose, but that will be pretty messy. Not easy to catch the fluid where it is located.

What you think????

 

[kennyd]

There is no need to bleed anything, the system will purge the air when you cycle the controls.

 

[crash325]

There is no need to bleed anything, the system will purge the air when you cycle the controls.

Thanks - Appreciated
Just worried about air going through the pump.

 

[crash325]

Got line on, not happy with how I routed it, so will change that tomorrow.

After a careful look the back hoe is a closed system, no place for the air to go, so I bled it anyway. A little mess, but did not think air going round & round would be good.

 

[DT86]

Save yourself the mess next time. There really is no need to bleed the line.

 

[crash325]

Save yourself the mess next time. There really is no need to bleed the line.

You and kenny probably both right. Me just a paranoid old man. Seemed to me sort of like air in a brake system.

 

[JD 4520]

You and kenny probably both right. Me just a paranoid old man. Seemed to me sort of like air in a brake system.

They are correct, it's not like a brake system in that regard. Interesting that you had a problem which suggest something isn't quite right but air isn't the problem.

 

[crash325]

They are correct, it's not like a brake system in that regard. Interesting that you had a problem which suggest something isn't quite right but air isn't the problem.

On a closed system how would the air escape???

Its working fine. I just don't like how I routed the hose. Didn't like how was originally routed. Its extra long so the back hoe can be used to remove & install it. Fairly quick & easy with 2 people. Sort of a pain when alone. have to look, move it a little, look again, & so on. Once lined up back the tractor onto it, a little more jerking around to get the pins in.

 

[DT86]

On a closed system how would the air escape???

To quote the movie Joe Dirt..
"Hows a rainbow made? Whys the sky blue? How does a posi track rear end on a Plymouth work? It just does."

 

[mjncad]

All hydraulic systems are closed systems; otherwise they would get contaminated with dirt. Are you saying your tractor uses a closed-center system versus an open-center one? If I'm correct, and I know KennyD knows the answer for certain; but an open-center system uses a constant displacement hydraulic pump, while a closed-center uses a variable displacement pump.

As for where the air goes; it goes back to the sump and is vented to atmosphere via whatever sump venting system is used. Yes, I know this sounds contradictory about having a vent to atmosphere in a closed system; but the sump vent is designed to let air pass while keeping dirt out.