FEL unresponsive -air?

[RobertH]

Hi all,

Last summer I added in quick disconnects to my FEL so I could take it off when not required. It was off most of the summer, then I re-attached it in advance of winter for snow duty. Since re-attaching the FEL it has not preformed properly. The boom will only raise to about 1/3 of normal full height and response is very slow, jumpy and erratic. The bucket is also slow to respond, although not as bad. I thought this might work itself out, but it hasn't and is now getting annoying. Yesterday I could not get the boom above a couple of feet max. Could this be explained by air in the system? I was very careful when installing the quick disconnects to fill the components completely with oil. I could see perhaps a small bubble getting in, but I can't see how this would explain the behaviour I am seeing. The rear hitch appears to work as per usual. I'm new to tractor ownership. Worked on all sorts of car engines etc for years but not experienced with hydraulics -yet. If you do get air in, how do you get it out? There seem to be no bleed valves anywhere on pipes, rams, or other parts.

Any tips or ideas appreciated.

Rob

 

[J_J]

Reset your QD's, one of then is not connected correctly.

In general, hyd systems are self bleeding as you operate the equipment.

 

[Gary Fowler]

Air in the system is not the problem as it will purge automatically within a few cycles thus no need for bleed valves or vents. Did you check your hydraulic oil level, this sounds like you may be running out of oil. When is the last time you drained the oil and checked for any water in the reservoir? You could have some ice in the reservoir that is keep the oil away from the pump. I would think that if the hydraulic reservoir is full and no ice in it , then the couplings may not be connected properly. Undo them and hook them back up and see how if performs. If the couplings are hooked properly, then the next step would be to put the tractor in a warm place to thaw out everything then try running it.

My money is on the coupling OR ice in the hydraulic reservoir.

 

[Tx Jim]

RobertH
Are you positive you don't have the connections criss-crossed between the boom & bucket circuits?

 

[RobertH]

Thanks for all the ideas.
I hope it may be as simple as re-seating the quick-connects. I will try that.

I have never drained out the oil/filter etc yet. Unfortunately I have no warm storage shed to thaw it out in, but I was wondering if warm weather might eventually bring a fix. This tractor has a combined trans-hydraulic system. I did check the level and topped it up.

When I put the new connects on I was pretty fanatical about labelling them, but won't hurt to check again.

I appreciate the feedback.

Rob

I was

 

[J_J]

Do a simple crackle test where you fill a spool with your hyd fluid and heat it up with a torch.

If it has water in it, it will crackle or sizzle.

 

[Tx Jim]

RobertH
I just noticed in your profile you have a JD 401 B. How long since hyd filters were changed and sump screen checked/cleaned?

 

[RobertH]

RobertH
I just noticed in your profile you have a JD 401 B. How long since hyd filters were changed and sump screen checked/cleaned?

Hi-good question. I have no idea. I have not had the tractor long. I will check this in the spring when I am planning a tear-apart and overhaul of the engine.

Regarding the ice in the oil screen idea, I would have thought that once the tractor was warmed up this would no longer be an issue, as the oil will be warmed by the transmission?

About the crackle test, I will try that as well. Still hope re-setting the connects might be the cure. I'm sure the other maintenance such as filters shoudl be done asap, as that could be limiting oil delivery to the pump, I am sure. Hard to do work on it here right now as it's outside, constantly well below freezing and deep in snow.

thanks again,

Rob

PS Tex Jim, are you familiar with the 401 B? Not that common a tractor, I think.

 

[MNBobcat]

Try running the loader to the max height and then curl the bucket up and down. lower. Raise. Repeat. That will fix it. Purges the air.

 

[Tx Jim]

Rob

PS Tex Jim, are you familiar with the 401 B? Not that common a tractor, I think.

No not really as I was employed at a JD "ag only" dealership BUT all JD closed center hyd systems are very similar especially when talking about utility or rowcrop versions. Before you do much I'd suggest checking the hyd sump screen.