loder leaking pressure

[newt88]

I replaced the hydrolic pump for my loader and it greatly improved the leaking off of pressure. Now it lifts loaded fine. The loader still leaks off about 6-8 inches and then stops. It holds fine until I change height and will will leak 6-8 inches again and stop. I'm puzzled. Any ideas

 

[andyspain]

Hi there, You are talking about a FL? When you say leaks 6" - 8" do you mean the bucket just drops on it's own?

 

[newt88]

yes, it wil leak off about 6-8 inches and then it seems to hold I haven't had time to watch it for a long period of time to see if it is just leaking slower or not. I've not seen or heard of anything quite like it. If you have an idea I'm all ears. Thanks

 

[andyspain]

Hi there, I can only think of air in the hydraulic oil. If a valve was not closing properly it would drop all the way, air would compress. Top of my head this I'm afraid. All the best Andy

 

[GuglioLS]

If there are no external leaks in the hydraulic system, then the best bet is that there is an internal leak within your cylinder. Your loader no doubt has a double acting cylinder. In any event, there are internal seals one of which may be allowing very slow leakage when your bucket is parked in a certain position. With time, they will only go from bad to worse. With what you describe, I would leave well enough alone until you have to use your pump frequently to maintain position while operating. The seals can be replaced when the time arrives assuming parts are available. Contaminants in hydraulic oil are the source of many a ruined seal hence best to keep clean fluid in your FEL. If the FEL is fairly new or the failure seems pre mature it could have been caused by what is known as "cavitation". This usually happens when the cylinder travel speed is greater than the fluid being pumped into it (air gets in past the seals and blows past the internal o-rings). A common condition when a cylinder is under heavy load and the valve is opened too far / fast for the load being placed on it.

Another source of this problem can be the control valve it could also be worn allowing fluid to leak past the valve back to the return line.
Not having seen your FEL, this is strictly an armchair shot in the dark. Good luck.

 

[Bigbear]

newt88, air in the lines, some times takes awhile to get it out and will act as a cushion until it hits the fluid. Same thing happens when your breaks go low on fluid, you refill, pump, pump, and then all the sudden they work. Just my 2cts, and experience.