TL220 Hydraulic droop

[AlFitz]

My TL220 is suffering from a slow droop in the arms (dropping in height) when shut down or under power without any input. It is very gradual but annoying. There is only 2500 hrs on the machine. There are no signs of any leaks on the lines. I thought is was the seals in the cylinders but doesn't make sense that when the rod retracts into the cylinder, it would still drop as there would be less room for compression. There is a dip in the bucket when elevating the arms indicating there is probably an issue with the self leveling control valve. Has anyone experienced this or would perhaps know what could be the cause? Thanks

 

[brdgbldr]

It is most likely that the seals on the pistons in the cylinder are worn out.
When this is the case, the fluid passes by the piston allowing the arms to bleed down.

 

[foton]

I agree it is most likely a cylinder,seldom is it the controls bypassing. You might want to replace your hydro filter , then pour it out into a relatively clean bucket and look for debris and the condition of the oil. If it is hour wise within replace or just refill do that when you have cylinders reworked. you make the call, I miss that from back in the day with the NFL, and why did it go away? A lot better than the half time shows ( mike J grabbing what most other men have, he I am not so sure) hahahahah

 

[AlFitz]

Thanks for the replies and info. I have serviced the machine and replaced all the fluids. The reason why I don't think it's the cylinders is because now when I lower the arms fully and bucket all the way down (lifting the machine) it doesn't drop at all. The workshop manual does mention, apart from checking the cylinders, to check the 'Float Control Solenoid' but the manual only shows a schematic diagram and not an actual drawing or picture of the device. I have no idea where this is to check.
Thanks again.

 

[AlFitz]

Fixed.
I tested all cylinders for bypassing. Nil issues.
When the arms were up and bucket was down, it didn't drop anyway near as bad. When the bucket was up slightly, it would drop.
There was obviously bleeding from bucket to arms somehow.
This lead me to checking the bucket levelling valve. After a clean and a bit of adjustment on the relief screws, it appears to have sorted the issue.

 

[cdmccul]

Great!