Slow lift

[ch1ch2]

With a bad piston seal oil can leak around the piston and return to tank while attempting to lift because it has a return route through the valve.
When the valve is closed and the bucket is up it can not because the oil has no where to go.
When the valve is closed and the bucket is being forced to lift from outside pressures it can leak around the piston and lift.

The difference being where the oil goes when it is not returning to the tank.

With the bucket in the air the oil has to go from the cylinder side to the rod side.
With the bucket being forced up it has to go from the rod side to the cylinder side.

The bucket can not fall down because in doing so the rod has to also enter the cylinder in addition to the oil, resulting in hydraulic lock.
The bucket can be lifted (with enough force) because in doing so the rod is extending from the cylinder and gives the oil a place to go while also creating a vacuum.

 

[texasranger556]

Ok, I see your point. To test the piston seals I would drop the bucket on a jack, then turn tractor off and relieve pressure by wiggling the loader valve. Disconnect the lift hose quick disconnect. Remove the jack. Hold loader valve in lift position to relieve rod end pressure. Does the bucket drop?

I just hate throwing parts at problems without being completely sure of the issue.

 

[ch1ch2]

I too hate throwing parts at a problem. That takes more money than I have.

In a minute I will be turning off my computer and I will not be able to get back to it for a week to 10 days.
So I do not want anyone thinking I am ignoring them.

 

[ch1ch2]

I am back.

So I guess no one has any experience with the cylinders on a 820 New Holland loader.

 

[davedj1]

Is it possible for you to swap the quick connects from the tilt to the lift? It would tell you right off if it's the cylinders or the valve. Good luck.
Post a pic of the rod end of your cylinder so we can see what it will take to get it apart. As someone said earlier, it ain't brain surgery.
I wouldn't think both cylinder seals would go at the same time but crazier things have happened.

 

[ch1ch2]

Is it possible for you to swap the quick connects from the tilt to the lift? It would tell you right off if it's the cylinders or the valve. Good luck.
Post a pic of the rod end of your cylinder so we can see what it will take to get it apart. As someone said earlier, it ain't brain surgery.
I wouldn't think both cylinder seals would go at the same time but crazier things have happened.

Done (see post 6)

 

[davedj1]

Done (see post 6)

sorry I missed that....

 

[TMGT]

Couple ways to check, remove lift cylinders, extend all the way out, remove rod end hoses only and activate valve to try and extend cylinder. If fluid comes out the the piston seal/s are bad.

You can also do it with the loader chained all the way up or with the loader held down with enough weight to overcome the lift or chained down somehow but its safer to remove the cylinders.

As for rebuilding, I'm not familiar with those particular cylinders but typically all you need is a pick set and some plastic prying tools like what you use for removing interior panels.

 

[ch1ch2]

Couple ways to check, remove lift cylinders, extend all the way out, remove rod end hoses only and activate valve to try and extend cylinder. If fluid comes out the the piston seal/s are bad.

You can also do it with the loader chained all the way up or with the loader held down with enough weight to overcome the lift or chained down somehow but its safer to remove the cylinders.

As for rebuilding, I'm not familiar with those particular cylinders but typically all you need is a pick set and some plastic prying tools like what you use for removing interior panels.

I like the first one. That way will also tell me if it is only one cylinder and how bad it is.
Thanks!

 

[crashz]

Have you checked your pump pressure (did I miss that)?