257 cat bucket leaking down

[tractormech]

Anybody have this bucket leakdown issue? It has a switch at the upper left that you flip to enable the auto level feature.It would work right and then start leaking down, Then start working right again. Now it leaks down all the time I capped the tilt cylinders off and the leakdown stopped so I know the cylinder seals are holding.Anyone ever dealt with this issue before? I hope there's a cartridge valve that can be replaced without changing the whole block.Any help or advice from anyone would be appreciated. Thanks!

 

[Mark250]

Hi just because you capped off the tilt cylinder lines doesn't mean the seals are bad
with the bucket weight pulling the cylinder rods forwards, the oil in the front part of the cylinder can transfer to the back of the cylinder due to the differences in volume between the two areas
Mark

 

[tractormech]

I guess I wasn't really clear on what was happening. The drifting down stopped when I capped the lines on the cylinders and had considerable weight in the bucket. The problem was intermittent-sometimes it leaked down and then it would stop and work fine,then start again with no warning. I didn't think it was o rings on the diverter valve cartridge because the problem came and went. I figure leaking o rings are leaking,all the time. I am leaning towards a bad cartridge hanging up and letting the bucket drift down. I was hoping someone else had experienced this and could share their solution. I don't like to throw parts at something-it's just too expensive.

 

[Mark250]

Some more information would be helpful. you haven't given serial number, model etc , History, Hi flow ,XPS- Hi flow.
I will assume it is a B series but will probably guess incorrectly
Here is a circuit for the level system for a B series which may help