FEL wont stay up

[PILOON]

FEL wont stay up ? Viagra comes to mind!

but if it does stay up for more than 4 hours call your mechanic immediately .
\(fortunately mechanics are easier to find than MD's)

 

[beaglebriar]

You won't lose much oil at all. Just cycle all the spools to relieve pressure before you pull the lines off. Shouldn't have to worry about air in the lines at all.

 

[MtnViewRanch]

You say that the loader will not hold the tractor up? Correct? So when the tractor works it's way down to the ground the rods are coming out of the cylinders, correct? Will the loader stay up? Raise the bucket to full height, see if the loader stays up. If it does not stay up, then your control valve is bad. Depending how fast it falls, you then have to make a judgment as to if you want to change out the control valve or not. Unless you have a really good valve, it will fall, just how fast is the real question and what is acceptable to you.

If it stays up for hours, then it is your piston seals that are bad, if it comes down in minutes, as in less than an hour, then your valve is bad.

Good luck.

 

[stan33]

Raise the bucket to full height, see if the loader stays up. Good luck.

Will do, thanks.

 

[Btown]

Thanks guys. There 'aint nothin quick disconnect about this loader! As those hoses at the valve are at almost the highest point, I guess there shouldn't be too much oil loss but will I still have to bleed the system and if so how?

Just cycle the loader and bucket several times it will work the air out.

 

[stan33]

You say that the loader will not hold the tractor up? Correct? So when the tractor works it's way down to the ground the rods are coming out of the cylinders, correct? Will the loader stay up? Raise the bucket to full height, see if the loader stays up. If it does not stay up, then your control valve is bad. Depending how fast it falls, you then have to make a judgment as to if you want to change out the control valve or not. Unless you have a really good valve, it will fall, just how fast is the real question and what is acceptable to you.

If it stays up for hours, then it is your piston seals that are bad, if it comes down in minutes, as in less than an hour, then your valve is bad.

Good luck.

Carried out testing but could not carry out to the letter so not sure if the result is conclusive. The bucket is off at the moment and I need another person to help me put it on.
I couldn't raise the boom to the full height as I recently fitted a new exhaust which has an outward pointing top: this obstructed the top of the boom going higher than just above horizontal. I can adjust this when it cools as the top is a removable spark arrestor.
So with those limitations:
I noticed that each time I raised the boom and then put the valve lever into neutral, the boom would immediately drop down about 4" then stop. Then, over the course of a full hour ie slowly, the boom lowered by another 3 or 4" and in the second hour, it dropped by another 7 or 8". ie about a foot in 2 hours.

 

[Tx Jim]

If it stays up for hours, then it is your piston seals that are bad, if it comes down in minutes, as in less than an hour, then your valve is bad.

Brian
For boom to settle lift cylinder piston must move into barrel of cylinder. """""""Where does the extra space come from that cyl rod will occupy that must displace the oil?????""""" If rod seal isn't leaking and control valve is holding a leaking piston seal will not cause FEL boom to settle because there's not sufficient area in cyl bore for trapped oil plus the rod. This principle is the same as a single acting cylinder on a combine platform or Mo-Co lift cyl. as in parts photo only snap ring in single acting cyl acts the same as piston(if packing is leaking) & nut in double acting cyl and just keeps rod from coming out of cyl bore. Piston packing on boom cylinder allows cyl to put down pressure on boom. In parts photo hyd oil pushes cyl rod out of bore but snap ring stops travel when header is lifted.
Thanks,Jim

 

[J_J]

Jim.

You are right in one respect, and that is that some of the oil in the base end can fill the rod side, but the rod side can only take the limit of the rod end space.

I have said this many times before.

If the piston seals are leaking and there is pressure/any weight at all, the fluid will transfer until the pressure is equal. The cyl should not fully collapse.

If the valve spool is worn, and leaking, then the boom will settle to the ground. The load,weight of the bucket and weight of the lift arms will cause this.

If you put a hyd gauge on both sides of the cyl, you will know.

If you have good seals, then the pressure on the cyl will be unequal.

Install the needle valve in the base end like I said and you will know.

Did you ever switch the work port hoses?

 

[LD1]

Bleeding down a foot over the course of 2 hours isnt terrible and I wouldnt spend the money to fix it. But if that is unacceptable to you, and there is no external leaks around the hoses or rod gland area, then the only cause is the valve.

 

[J_J]

Using a SA cyl with bad piston seals, and weight on rod, where do you think the fluid will go.

It will transfer to the air space in the rod end. If you cycle the SA cyl many times with leaking piston seals, fluid will come out the rod side vent hole.

Loader drop In most cases is a little of both, valve spools and piston seals leaking.

That is my story and I am sticking to it.

What causes an old ram jack with no seals to leak? Worn parts.

What causes a new ram jack to leak? Quality control.